U.S. patent application number 13/072981 was filed with the patent office on 2012-01-19 for ground roast coffee tablet.
This patent application is currently assigned to THE FOLGERS COFFEE COMPANY. Invention is credited to Jerry Douglas Young.
Application Number | 20120015094 13/072981 |
Document ID | / |
Family ID | 45467191 |
Filed Date | 2012-01-19 |
United States Patent
Application |
20120015094 |
Kind Code |
A1 |
Young; Jerry Douglas |
January 19, 2012 |
GROUND ROAST COFFEE TABLET
Abstract
A ground roast coffee tablet which is capable of being brewed in
a conventional automatic drip coffee maker, and which exhibits
sufficient strength to withstand all aspects of manufacture,
handling, packaging, transport without breakage but also readily
disintegrates when contacted with hot water during brewing, is made
by subjecting conventional ground, roasted coffee to a multi-step
compaction process in which at least two compression steps are
carried out in the same compaction die.
Inventors: |
Young; Jerry Douglas;
(Cincinnati, OH) |
Assignee: |
THE FOLGERS COFFEE COMPANY
Orrville
OH
|
Family ID: |
45467191 |
Appl. No.: |
13/072981 |
Filed: |
March 28, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12753332 |
Apr 2, 2010 |
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13072981 |
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61318028 |
Mar 26, 2010 |
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61168027 |
Apr 9, 2009 |
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Current U.S.
Class: |
426/595 ;
426/433; 426/454 |
Current CPC
Class: |
A23F 5/14 20130101; A23F
5/125 20130101; A23F 2200/00 20130101 |
Class at
Publication: |
426/595 ;
426/454; 426/433 |
International
Class: |
A23F 5/12 20060101
A23F005/12; A23F 5/26 20060101 A23F005/26 |
Claims
1-172. (canceled)
173. A free-standing coffee tablet for use in an automatic drip
coffee maker (ADC), the coffee tablet comprising at least about 91%
ground roast coffee, having a density of at least 0.90 g/cm.sup.3,
and exhibiting a hardness of at least about 30 N (Newtons), a
friability of no greater than about 10%, and readily disintegrates
when contacted with hot water during brewing in the ADC.
174. The coffee tablet of claim 173, which further comprises a
binder.
175. The coffee tablet of claim 174, wherein the binder comprises a
liquid flavor carrier or propylene glycol.
176. The coffee tablet of claim 175, wherein the liquid flavor
carrier has a viscosity of .about.15 to .about.65 cP and a surface
tension of .about.30 to .about.50 dynes/cm at 25.degree. C.
177. The coffee tablet of claim 173, which contains instant coffee
in an amount of .gtoreq..about.0.5 wt. % and .ltoreq..about.15 wt.
%, based on the total amount of coffee in the tablet.
178. The coffee tablet of claim 173, which has a volume less than
about 3.2 cm.sup.3.
179. The coffee tablet of claim 173, which comprises at least about
96% coffee.
180. The coffee tablet of claim 173, wherein the automatic drip
coffee maker (ADC) has a water delivery rate of approximately
2.5-3.1 g/sec; ten (10) of the tablets, unbroken, are capable of
brewing with 1420 ml of water in the ADC a consumable coffee
beverage having an absorbance per gram of >0.07; and the coffee
tablets exhibit a yield greater than 26% when brewed.
181. A process for producing a coffee tablet comprising subjecting
ground roast coffee to a multi-step compaction process including a
pre-compression step and a subsequent main compression step, the
pre-compression step being carried out at a lower compaction force
but in the same compaction die as the main compression step so as
to produce a coffee tablet exhibiting a hardness when dry of at
least about 30 N (Newtons), a friability when dry of no greater
than about 10%, and readily disintegrates when contacted with hot
water during brewing in the ADC.
182. The process of claim 181, wherein the tablet is made from
ground roast coffee derived from coffee beans that have been dried
to a moisture contents of .about.1% to .about.7 wt. % before
roasting, grinding, and tabletting.
183. The process of claim 181, wherein the pre-compression step is
carried out at a pressure of >.about.36.1 MPa and
.ltoreq..about.106.1 MPa.
184. The process of claim 181, wherein the main compression step is
carried out at a pressure of >.about.53.0 MPa and
<.about.169.7 MPa.
185. The process of claim 181, wherein at least one of the
compression steps has a compression dwell time<75
milliseconds.
186. The process of claim 181, wherein the delay between the end of
the pre-compression dwell time and the beginning of the main
compression dwell time is about 80-900 milliseconds.
187. The process of claim 181, wherein the total duration from the
beginning of the pre-compression dwell time to the end of the main
compression dwell time is approximately 0.1-1.0 seconds.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to, and any other benefit
of, U.S. Provisional Patent Application Ser. No. 61/318,028,
entitled GROUND ROAST COFFEE TABLET and filed Mar. 26, 2010. This
application is also a continuation-in-part of and claims priority
to, and any other benefit of, U.S. patent application Ser. No.
12/753,332 (Attorney Docket No. 26416/05900), entitled GROUND ROAST
COFFEE TABLET and filed Apr. 2, 2010, which claims priority to, and
any other benefit of, U.S. Provisional Patent Application Ser. No.
61/168,027, entitled GROUND ROAST COFFEE TABLET and filed Mar. 26,
2010. The entire disclosures of each of the above references is
fully incorporated herein by reference.
BACKGROUND
[0002] Automatic Drip Coffee makers ("ADCs") are designed for
processing "ground roast coffee" or "coffee," i.e., granulated
coffee obtained by grinding previously roasted coffee beans.
Because of differences in flavor strength among different coffees,
as well as variations in personal taste, consumers may find it
difficult to determine the correct dose (amount) of coffee to use
for brewing pots of different sizes.
[0003] To deal with this problem, a number of products have been
introduced in which the coffee is provided in standardized doses.
For example, filter packs in which a predetermined amount of
coffee, e.g., enough coffee to brew 4, 10 or 12 servings of brewed
coffee, is provided in a filter paper container. However, this
approach cannot be used for brewing one, or only a few, servings of
coffee, as the consumer is required to make the amount of servings
for which the filter pack is designed. In addition, it is difficult
to change the strength of the brewed coffee.
[0004] In an alternate approach, single serving "pods" have been
provided in which enough ground roast coffee for brewing only a
single serving is housed in a filter paper container. However,
single serving pods must have a specific configuration to fit
brewer(s) for which they are designed. Machines used to brew coffee
with these pods are fundamentally different from automatic drip
coffee makers. They are also limited to making a single cup at a
time, which limits their usefulness in making larger amounts of
brewed coffee.
[0005] A further approach combines the idea of a single cup brew is
found in products such as Folgers.RTM. coffee singles. These can be
made with mixtures of instant and ground roast coffee. While they
do not have to fit a particular brewer, they still are designed for
only a single cup of coffee.
[0006] In still another approach, separate "tablets" are provided
which are made solely out of instant coffee (also referred to as
soluble coffee). However, instant coffee is not preferred by some
consumers.
SUMMARY
[0007] In accordance with this invention, coffee tablets for use in
a conventional automatic drip coffee maker are provided.
[0008] A first exemplary coffee tablet is made by a multi-step
compaction process in which at least a first compression and a
separate second compression are carried out in the same compaction
die in such a manner that the coffee tablet obtained exhibits a
hardness of at least about 30 N (Newtons), a friability of no
greater than about 10%, and readily disintegrates when contacted
with hot water during brewing in an automatic drip coffee maker
(ADC).
[0009] A second exemplary coffee tablet is made by a multi-step
compaction process in which a pre-compression step is carried out
at a lower compaction force but in the same compaction die as the
main compression step so that the coffee tablet obtained exhibits a
hardness of at least about 30 N (Newtons), a friability of no
greater than about 10%, and readily disintegrates when contacted
with hot water during brewing in an ADC.
[0010] A third exemplary coffee tablet comprises at least about 91%
ground roast coffee, has a density of at least 0.95 g/cm.sup.3, and
exhibits a hardness of at least about 30 N (Newtons), a friability
of no greater than about 10%, and readily disintegrates when
contacted with hot water during brewing in an ADC.
[0011] A fourth exemplary coffee tablet comprises at least about
91% ground roast coffee and at least 1.5 wt. % propylene glycol,
and exhibits a hardness of at least about 30 N (Newtons), a
friability of no greater than about 10%, and readily disintegrates
when contacted with hot water during brewing in an ADC.
[0012] A fifth exemplary coffee tablet comprises at least about 91%
ground roast coffee and at least 1.5 wt. % of a liquid flavor
carrier, and exhibits a hardness of at least about 30 N (Newtons),
a friability of no greater than about 10%, and readily
disintegrates when contacted with hot water during brewing in an
ADC.
[0013] A sixth exemplary coffee tablet comprises at least about 91%
ground roast coffee and an amount of instant coffee large enough to
improve at least one mechanical property of the tablet selected
from binding strength, ease of disintegration, and brewing
efficiency (as determined by the amount of coffee solids extracted
from the tablet when subjected to brewing in an ADC).
[0014] A seventh exemplary coffee tablet comprises at least about
91% ground roast coffee, and exhibits a hardness of at least about
50 N (Newtons) and a friability of no greater than about 3.5%, and
readily disintegrates when contacted with hot water during brewing
in an ADC.
[0015] An eighth exemplary coffee tablet comprises at least about
91% ground roast coffee, has a mass less than about 4 g, and
exhibits a friability of no greater than about 6% and readily
disintegrates when contacted with hot water during brewing in an
ADC having a water delivery rate of approximately 2.5-3.1 g/sec,
wherein ten (10) of the tablets, unbroken, are capable of brewing
with 1420 ml of water in an automatic drip coffee maker a
consumable coffee beverage having an absorbance of 1.1-3.5 or
1.25-2.75 or 1.7-2.5, and wherein the coffee tablets exhibit a
yield greater than 26% when brewed in the ADC.
[0016] A ninth exemplary coffee tablet comprises at least about 91%
ground roast coffee and exhibits a friability of no greater than
about 6%, and readily disintegrates when contacted with hot water
during brewing in an ADC having a water delivery rate of
approximately 2.5-3.1 g/sec, wherein ten (10) of the tablets,
unbroken, are capable of brewing with 1420 ml of water in an
automatic drip coffee maker a consumable coffee beverage having an
absorbance per gram of >0.07 or >0.09, and wherein the coffee
tablets exhibit a yield greater than 26% when brewed in the
ADC.
[0017] A tenth exemplary coffee tablet is made by a multi-step
compaction process in which at least a first compression and a
separate second compression are carried out in the same compaction
die in such a manner that the coffee tablet obtained exhibits a
hardness of at least about 40 N (Newtons) and a friability of no
greater than about 6%, and readily disintegrates when contacted
with hot water during brewing in an ADC.
[0018] An eleventh exemplary coffee tablet is made by a multi-step
compaction process in which a pre-compression step is carried out
at a lower compaction force but in the same compaction die as the
main compression step wherein the pre-compression compaction force
is .about.20% to <100%, .about.30% to .about.90%, .about.40% to
.about.80%, or .about.50% to .about.75%, or .about.50% to
.about.60% of the compaction force used in the main compression
step.
[0019] A twelfth exemplary coffee tablet is made by a multi-step
compaction process in which a pre-compression step is carried out
at a lower compaction force but in the same compaction die as the
main compression step wherein the pre-compression pressure is
.about.20% to <100%, .about.30% to .about.90%, .about.40% to
.about.80%, or .about.50% to .about.75%, or .about.50% to
.about.60% of the pressure used in the main compression step.
[0020] An exemplary process for producing a coffee tablet includes
subjecting ground roast coffee to a multi-step compaction process
including a pre-compression step and a subsequent main compression
step, the pre-compression step being carried out at a lower
compaction force but in the same compaction die as the main
compression step so as to produce a coffee tablet exhibiting a
hardness when dry of at least about 30 N (Newtons), a friability
when dry of no greater than about 10%, and readily disintegrates
when contacted with hot water during brewing in the ADC.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] This invention may be more readily understood by reference
to the following drawings wherein:
[0022] FIG. 1 illustrates the effect achieved on the hardness,
friability and extraction efficiency of the inventive coffee
tablets when the pre-compression force used in the inventive
manufacturing process is altered;
[0023] FIG. 2 shows the results obtained in the following working
Example 6 and illustrates how including instant coffee in the
inventive ground roast coffee tablets allows a more efficient fill
and higher operating speeds of the automatic tabletting machine
used to make these tablets;
[0024] FIGS. 3 and 4 illustrate the results obtained in the
following working Example 11 in which a flavorant is included in
the inventive ground roast coffee tablets;
[0025] FIGS. 5 and 6 illustrate results obtained in the following
working Example 19 in which inventive coffee tablets and their
roasted and ground coffee counterpart have been brewed to measure
extracted coffee solids and cumulative yields over the course of
each brew, as compared to the brew characteristics of a competitive
coffee tablet
[0026] FIGS. 7 and 8 illustrate additional results obtained in the
following working Example 19 in which other inventive coffee
tablets and their roasted and ground coffee counterpart have been
brewed to measure extracted coffee solids and cumulative yields
over the course of each brew; and
[0027] FIGS. 9 and 10 illustrate the results obtained in the
following working Example 19 in which other inventive coffee
tablets have been brewed to measure extracted coffee solids and
cumulative yields over the course of each brew.
DETAILED DESCRIPTION
Terminology
[0028] Unless otherwise indicated expressly or from context, the
following terms will have the following meanings:
[0029] "Binder" means a material which improves the strength of the
ground roast coffee tablets made in accordance with this invention.
"Binder" does not include ingredients which, although providing
some binding activity, provide some other function in significant
amount such as contributing to taste, health effects, etc.
[0030] "Brewed coffee" means a liquid coffee drink formed by
extracting coffee solids from ground, roasted coffee beans or
substitutes. "Brewed coffee" includes coffee drinks formed from
regular coffee, decaffeinated coffee, instant coffee and coffee
substitutes such as chicory.
[0031] "Coffee," "regular coffee," and "ground roast coffee" mean a
mass of solid, non-decaffeinated particles derived by comminuting
roasted coffee beans.
[0032] "Coffee product" means any product derived from coffee
beans.
[0033] "Coffee substitute" refers to a substance which is
customarily used as a replacement for coffee such as ground roast
chicory, roasted soybeans, and roasted grains such as corn/maize,
barley, rye, oats, rice, wheat germ, spelt, buckwheat, and
millet.
[0034] "Decaffeinated coffee" refers to a solid derived from coffee
beans, both roasted and unroasted, which contain a substantially
reduced concentration of caffeine.
[0035] "Density," as it relates to ground roast coffee and unless
otherwise indicated, refers to the number of ounces of that coffee
that are needed to fill a container having a predetermined standard
volume. Historically in the United States, one pound (16 ounces or
454 g) of ground roast coffee had a standard density of .about.0.4
g/cc and a conventional moisture content of about 1-7%. However,
technologies have allowed lower density coffees to be made, so
today a more standard density is .about.0.33 g/cc. Even lower
densities are possible, such as .about.0.263 g/cc.
[0036] "Free-standing" in reference to a coffee tablet means that
the coffee tablet is not housed in a filter paper container (or
other container made from a similar material) which is intended to
remain in place, around the tablet, when the tablet is contacted
with hot water for brewing.
[0037] "Flavor Carrier" refers to a material for containing,
carrying, or otherwise being mixed with coffee flavorant to
facilitate using the coffee flavorant. Coffee flavorants are
normally added to coffee products by means of such flavor carriers,
which are provided to make dispensing, metering and mixing of the
flavorant with the coffee product easier. For example flavorants
may be added to a flavor carrier in a proportion so that a
consistent weight percentage (e.g., 3%) of the final
carrier-containing flavorant compositions can be added to ground
roast coffee regardless of the particular flavorant or flavor
carrier. Flavor carriers can be in dry, liquid, or paste forms and
carrier-containing flavorant compositions added to ground roast
coffee can be in dry, liquid, or paste forms.
[0038] "Instant coffee" refers to a flowable, particulate coffee
product that has been made by evaporating water from a previously
made brewed coffee, usually by concentration and drying. Typical
drying means, such as spray drying and freeze drying are known in
the art. An example of instant coffee production may be found in
U.S. Pat. No. 3,700,466, the entire disclosure of which is
incorporated herein by reference.
[0039] "Standard serving of brewed coffee" refers, for each country
of the world, brewed coffee as customarily served in that country.
For example, in the United States, brewed coffee is served in two
different ways, regular strength and espresso strength. In both
cases, about 3-5 grams of ground roast coffee is used to make the
brewed coffee. An exemplary Folgers brand medium roast, ADC ground
coffee is brewed using about 3 grams of the ground roast coffee
having a density of about 0.33 g/cc to make the brew. Regular
strength coffee is made with about 5-6 fluid ounces (.about.150-175
ml) of water, while espresso strength coffee is made with about 1.9
fluid ounces (.about.55 ml) of water. Thus, in the United States, a
"standard serving of brewed coffee" will be understood as referring
to 5-6 fluid ounces (.about.150-175 ml) of regular strength brewed
coffee as well as to roughly 1.9 fluid ounces (.about.55 ml) of
espresso strength brewed coffee.
Automatic Drip Coffee Makers
[0040] This invention is intended for use with any automatic drip
coffee maker ("ADC") designed for producing brewed coffee by hot
water extraction in which hot water is dripped onto a bed of ground
roast coffee. While hot water at a wide range of temperatures may
be employed, exemplary temperature ranges for hot water for brewing
may include about 70-120.degree. C., about 80-110.degree. C., about
80-100.degree. C., or about 90-100.degree. C.
[0041] Normally, the ground roast coffee is deposited in a "brew
basket," i.e., a container having an open top and a floor defining
one or more outlet openings, the brew basket containing a paper or
metal mesh or plastic mesh coffee filter in most instances. Brew
baskets are often shaped in the form of a truncated cone or other
similar wedge shapes, so that their side walls direct flow to the
more confined area of the containers' floor. The most common brew
baskets are referred to as "basket" style and "cone" style. Once
activated, the machine automatically heats water previously placed
in its water reservoir and then causes this heated brewing water to
drip down onto the coffee bed in the brew basket over a suitable
period of time (the "brewing cycle time"). Another style of machine
has a reservoir of hot water that is displaced by new water added.
In either case, the machine delivers hot water at or slightly above
atmospheric pressure, which is somewhat below boiling to about
boiling, to the brew basket. As the water passes through the coffee
bed, coffee flavor solids are extracted from the ground roast
coffee, thereby producing brewed coffee. The brewed coffee so made
then passes through the coffee filter and then through the outlet
opening or openings in the brew basket, where it is collected in a
suitable carafe normally positioned below the outlet opening or
openings.
[0042] Automatic drip coffee makers come in many different sizes.
Most automatic drip coffee makers for consumer use are designed to
produce 4-12 standard servings of brewed coffee per brewing cycle.
A first variation of automatic drip coffee makers have an option
for brewing one to three standard servings. A second variation of
automatic drip coffee makers, typically known as "4 cup" brewers,
are designed to brew up to four standard servings. A few are even
capable of brewing a single cup, although these are typically high
pressure brewers and not "drip" brewers. Automatic drip coffee
makers for commercial or industrial use are typically designed for
producing 10 to 30 standard servings of brewed coffee per brewing
cycle. The inventive ground roast coffee tablets can be used with
all such automatic drip coffee makers, regardless of the
configuration of their brew baskets. Thus, the minimum number of
servings for which a coffee brewer is designed can vary from
machine to machine and may be one serving, four servings, ten
servings, or some other number of servings.
[0043] While the inventive coffee tablets of the present
application may advantageously be used with many different types of
coffee makers, including many different types of automatic drip
coffee makers, the specific brew performance characteristics (e.g.,
yield, % brew solids, total brew solids, absorbance, etc.)
described herein correspond to brewing the inventive coffee tablets
in a 4-12 cup automatic drip coffee maker ("ADC") having a water
delivery rate of approximately 2.5 g/sec to 3.1 g/sec, for example,
a water delivery rate of about 2.7 to 2.8 g/sec. Two such ADC's are
the Mr. Coffee.RTM. Model DR13 coffee maker and the Mr. Coffee.RTM.
Accel (Model PRX 23) coffee maker, both of which have a water
delivery rate of approximately 2.75 g/sec. As expected, ADC's
having substantially higher water delivery rates may produce lower
total extraction (and corresponding lower brew solids
concentrations, yields, and absorbances), as the faster flowing
water has less time to absorb the coffee solids. However, relative
to the brew performance of the corresponding roasted and ground
coffee under the same brewing conditions, the relative brew solids
indices, yield ratios, or absorbance ratios of coffee brewed using
an ADC with a higher water delivery rate (for example, the
Bunn.RTM. Pour-Omatic GR, having a water delivery rate of
approximately 10 to 11 g/sec) may be comparable to those described
herein for ADC's having a water delivery rate of approximately 2.5
g/sec to 3.1 g/sec.
Ingredients
[0044] The coffee tablets of this invention can be made from
virtually any type of ground roast coffee.
[0045] Ground roast coffee is made from coffee beans, which are the
seeds of "cherries" that grow on coffee trees in a narrow
subtropical region around the world. There are many coffee
varieties, however, it is generally recognized that there are two
primary commercial coffee species: Coffea arabica (herein
"Arabica(s)") and Coffea canephora var. robusta (herein
"Robusta(s)"). Coffees from the species arabica may be described as
"Brazils," which come from Brazil, or "Other Milds" which are grown
in other premium coffee producing countries. Premium Arabica
countries are generally recognized as including Colombia,
Guatemala, Sumatra, Indonesia, Costa Rica, Mexico, United States
(Hawaii), El Salvador, Peru, Kenya, Ethiopia and Jamaica. Coffees
from the species canephora var. robusta are typically used as a low
cost extender or as a source of additional caffeine for Arabica
coffees. These Robusta coffees are typically grown in the lower
regions of West and Central Africa, India, South East Asia,
Indonesia, and Brazil. See, US 2008/0118604, the disclosure of
which is incorporated herein by reference.
[0046] Virtually any of the above varieties and types of coffees
can be used to make the inventive coffee tablets. One ground roast
coffee without any binder or liquid flavor carrier acting as a
binder resulted in tablets with very poor hardness and friability.
This coffee had a coffee bulk density of about 0.353 g/cm.sup.3, a
moisture content of about 2.2%, and a relatively high percentage of
"fines." While not intending to be bound by any particular theory,
it is believed that the combination of low moisture, high density,
and a high fines percentage combined to cause these relatively poor
results. Mixtures of different coffee varieties and types can also
be used.
[0047] When removed from the coffee cherry, coffee beans normally
have a distinctly green color and a high moisture content.
Therefore, they are normally dried prior to export, typically to a
moisture content of about 12%. Historically, solar drying was the
method of choice, although machine drying is now normally used due
to the reliability and efficiency of the machine dryers available
for this purpose. See, Sivetz et al., Coffee Technology, "Drying
Green Coffee Beans", pp. 112-169 (1979). Sivetz also highlights the
irreversible damage over-drying can have on coffee quality.
[0048] After drying to a moisture content of about 12%, the coffee
beans are typically exported to consuming nations where they are
processed into conventional ground roast coffee by roasting
followed by grinding. Any of the variety of roasting techniques
known to the art can be used to roast the green coffee in the
process of this invention. In the normal operation of preparing
conventional roast and ground coffee, coffee beans may be roasted
in a hot gas medium at temperature ranges of about
176.8-371.1.degree. C. (350-700.degree. F.), or about
176.8-260.degree. C. (350-500.degree. F.), or about
204.4-232.2.degree. C. (400-450.degree. F.), or about
260-287.8.degree. C. (500-550.degree. F.), or about
315.6-348.9.degree. C. (600-660.degree. F.), with the time of
roasting being dependent on the flavor characteristics desired in
the coffee beverage when brewed. Where coffee beans are roasted in
a batch process, the batch roasting time at the hereinbefore given
temperatures is generally from about 2 minutes to about 20 minutes,
and may, for example, be about 10-20 minutes or about 12-18
minutes, or may be about 2-10 minutes, or about 2-6 minutes, or
about 2-4 minutes, or about 2-3 minutes. Where coffee beans are
roasted in a continuous process, the residence time of the coffee
beans in the roaster is typically from about 30 seconds to about 9
minutes, and may, for example, be about 30 seconds to 6 about
minutes, or about 30 seconds to about 4 minutes, or about 1-3
minutes. The roasting procedure can involve static bed roasting as
well as fluidized bed roasting. A preferred type of roasting would
be using fast roasters. While any method of heat transfer can be
used in this regard, convective heat transfer, especially forced
convection, is normally used for convenience. The convective media
can be an inert gas or, more typically, air. Typically, the beans
are charged to a bubbling bed or fluidized bed roaster where they
contact a hot air stream at inlet air temperature of from about
350.degree. to about 1200.degree. F. (about 177.degree. C. to about
649.degree. C.) preferably from about 400.degree. F. to about
800.degree. F. (about 204.degree. C. to about 427.degree. C.), at
roast times form about 10 seconds to not longer than about 5.5
minutes, preferably from about 10 to about 47 seconds.
[0049] As well known to coffee professionals, it is conventional to
refer to the degree or extent to which coffee beans are roasted in
terms of their Hunter color level. The Hunter Color "L" scale
system is generally used to define the color of the coffee beans
and the degree to which they have been roasted. Hunter Color "L"
scale values are units of light reflectance measurement, and the
higher the value is, the lighter the color is since a lighter
colored material reflects more light. Thus, in measuring degrees of
roast, the lower the "L" scale value the greater the degree of
roast, since the greater the degree of roast, the darker is the
color of the roasted bean. This roast color is usually measured on
the roasted, quenched and cooled coffee beans prior to subsequent
processing (e.g., grinding and/or flaking) into a brewed coffee
product. However, color may be measured on finished product, in
which case the color will be designated as such. See, pages 985-95
of R. S. Hunter, "Photoelectric Color Difference Meter," J. of the
Optical Soc. of Amer., Volume 48 (1958).
[0050] The ground roast coffee used to make the inventive coffee
tablets can be made from coffee beans roasted to any desired roast
color from about 10 L (very dark) to about 25 L (very light). In
some embodiments, it is contemplated that the coffee beans will be
fast roasted to an average color of from about 13 to about 19
Hunter L units, preferably from about 14 to about 18 Hunter L
units, and even about 15 to about 17 Hunter L units.
[0051] Once the coffee beans are roasted, they are ground to a
desired average particle size. Average particles sizes on the order
of as low as 250 .mu.m (microns) and as high as 3 mm, as measured
by Laser Diffraction on a Sympatec Rodos Helos laser particle size
analyzer, are conventional. Average particle sizes on the order of
400 .mu.m to 1,000 .mu.m, 500 .mu.m to 800 .mu.m, and even 650
.mu.m to 750 .mu.m, 800 .mu.m to 950 and 850 .mu.m to 900 .mu.m are
more interesting. The coffee beans may be ground to other average
particle sizes, including for example, average particle sizes of
about 400 .mu.m to 1.5 mm, or about 300 .mu.m to about 1,000 or
even about 1-2 mm. It is also recognized that larger coffee
particles may be broken down during tablet compaction, resulting in
smaller average particle sizes within the compacted coffee
tablet.
[0052] The ground roast coffee tablets of this invention can be
made from ground roast coffees ground to any of these particle
sizes. Coffee flakes can also be used. Of course, there can be a
size distribution around these mean particle sizes, so that the
grind can be further characterized by breadth of distribution. One
convenient measure is Q250, the percent of particles less than 250
microns, which represents the amount of finer particles (or
"fines") that are included in the distribution and that help make
up the mean size.
[0053] As appreciated by skilled coffee professionals, different
ground coffees exhibit different bulk densities depending on the
type of coffee used, the method by which the coffee is roasted, the
color of the roasted coffee, the particle size to which the coffee
is ground, moisture content, and other factors. In accordance with
this invention, the inventive coffee tablets can be made for ground
roast coffee having any conventional density. So, for example, the
inventive coffee tablets can be made from ground roast coffees
having "regular" densities ranging between about 0.26 g/cc to 0.35
g/cc such as, for example, 0.263 g/cc, 0.288 g/cc, 0.325 g/cc, and
0.35 g/cc, if desired.
[0054] Alternatively, the inventive coffee tablets can also be made
for ground roast coffees having greater or lesser densities, if
desired. For example, the inventive coffee tablets can be made from
high density coffees having densities of >0.4 g/cc, e.g.,
densities of up to .about.0.6 g/cc, although even higher densities
are contemplated. Similarly, the inventive coffee tablets can be
made from low density coffees having densities of <0.18 g/cc to
0.26 g/cc, e.g., densities of 0.18 g/cc to 0.26 g/cc, 0.20 g/cc to
0.25 g/cc, or even 0.22 g/cc to 0.23 g/cc (such as .about.0.19
g/cc, .about.0.20 g/cc, .about.0.21 g/cc, .about.0.22 g/cc,
.about.0.23 g/cc, .about.0.24 g/cc or even .about.0.25 g/cc). In
this regard, see U.S. Pat. No. 5,160,757 for a description of how
to make low density coffees and U.S. Pat. No. 5,227,188 for a
description of how to make high density coffees. The entire
disclosures of both of these patents are incorporated herein by
reference.
[0055] As appreciated by skilled coffee professionals, different
ground coffees also exhibit different moisture contents depending
on the type of coffee used, the method by which the coffee is
roasted, the color of the roasted coffee, the particle size to
which the coffee is ground, and other factors. So, for example, the
inventive coffee tablets can be made from ground roast coffees
having moisture contents of .about.1 to .about.7 wt. %, .about.2 to
.about.7 wt. %, .about.2 to .about.6 wt. %, .about.3 to .about.6
wt. % and .about.4 to .about.5.5 wt. %. Some ground roast coffees
having a moisture content less than .about.2.5 wt. % may not make
tablets with acceptable friability without the use of a binder or
liquid flavor carrier acting as a binder; thus, any of these ranges
might have a lower boundary of .about.2.5 wt. %.
[0056] Generally speaking, the inventive coffee tablets can also be
made from mixtures of two or more of the coffees described above.
So, for example, the inventive coffee tablets can be made from
mixtures of ground roast coffees having different densities,
different Hunter L colors, different particle sizes, different
moisture contents, and different combinations thereof (i.e., one
ground roast coffee could have a low density and a high moisture
content while another ground roast coffee could have a medium
density and a low moisture content). Thus, the inventive coffee
tablets can be made from mixtures of regular and high density
coffees, mixtures of regular and low density coffees, mixtures of
high and low density coffees, and mixtures of high, regular and low
density coffees, if desired. In addition, the inventive coffee
tablets can be made from mixtures ground roast coffees having high
and low Hunter L color numbers, large and small average particle
sizes, etc.
[0057] In addition to the above ground roast coffees, additional
ingredients can be included in the ground roast coffee tablets of
this invention. For example, decaffeinated varieties of the above
coffees can be used in addition to, or in place of, the ground
roast coffees described above. Similarly, coffee substitutes such
as ground chicory, roasted soybeans, and roasted grains such as
corn, rye, wheat, barley, oats, rice, wheat germ, spelt, buckwheat,
and millet can be included in the inventive ground roast coffee
tablets. (Instant coffee is not a "coffee substitute" in this
context.) Coffee flavorings, as further discussed below, can be
included. Also, various excipients such as binders and
disintegration aids can be included.
[0058] Examples of suitable solid particulate binders include
starches, sugars, modified starches, maltrodextrins, polydextroses,
carrageenans, gums, soluble fibers, celluloses, waxes, gelatin,
sugars, including sucrose, glucose, dextrose, molasses and lactose,
natural and synthetic gums, including acacia sodium alginate,
extract of Irish moss, panwar gum, ghatti gum, mucilage of isapol
husks, carboxymethylcellulose, methylcellulose,
polyvinylpyrrolidone, Veegum, larch arabogalactan,
polyethyleneglycol, ethylcellulose, any salts of these compounds,
and mixtures thereof can be included as binders. More interesting
solid binders are carboxymethylcellulose, ethyl cellulose,
maltodextrin, gelatin, gum arabic, gum agar, modified corn starch,
and mixtures thereof. See, for example, EP 813816 B1, U.S. Pat. No.
6,090,431, U.S. Pat. No. 6,277,428, EP 0229920 and U.S. Pat. No.
1,951,357.
[0059] Surprisingly, it has been found that some liquid flavor
carriers act as a binder in coffee tablets. Suitable liquid flavor
carriers include those having viscosities of 15 to 65 cP
(centipoise), 35 to 65 cP, 40 to 60 cP, or even 45 to 56 cP and
surface tensions of 30 to 50 dynes/cm, 35 to 45 dynes/cm, or even
35 to 40 dynes/cm at 25 C. Propylene glycol is a good example of a
liquid flavor carrier that acts as a binder in coffee tablets.
Other examples include but are not limited to glycerin, other
polyols, and polyethylene glycol (PEG).
[0060] Binders, if used, will normally be present in an amount of
.ltoreq..about.10 wt. %, .about.0.5 to .about.7 wt. %, .about.1 to
.about.5 wt. %, or even .about.1.5 to 4 wt. %, or even .about.2 to
.about.4 wt. %, based on the weight of the entire composition.
However, addition of one or more binders is not required, and
indeed in many embodiments the inventive coffee tablets are
essentially free of binders.
[0061] Mixtures of all of the above ingredients, i.e., mixtures of
different ground roast coffees, different ground roast
decaffeinated coffees, different ground roast coffee substitutes,
different flavorings and/or different excipients, can also be used.
If so, the amount of ground roast coffee (both regular and
decaffeinated) included in the ground roast coffee solid used to
make the inventive ground roast coffee tablets will normally be at
least about 50 wt. %, more typically at least about 75 wt. %, at
least about 80 wt. %, at least about 85 wt. %, at least about 90
wt. %, at least about 91 wt. %, at least about 92.5 wt. %, or even
at least about 95 wt. %., based on the weight of the tablets
ultimately produced. Moreover, although some or all of this ground
roast coffee can be decaffeinated, it is also desirable at least in
some embodiments that essentially all of the ground roast coffee is
"regular," i.e., non-decaffeinated coffee. Embodiments in which at
least 5 wt. %, at least 10 wt. %, at least 25 wt. %, at least 50
wt. %, at least 75 wt. %, or even at least 90 wt. % of the ground
roast coffee in the inventive tablets is decaffeinated are
contemplated, as are embodiments in which essentially all of the
ground roast coffee in the tablets is decaffeinated.
Tablet Size and Configuration
[0062] Although the inventive coffee tablets can be made in any
size, they are normally designed at least in some embodiments to
produced a single standard serving of brewed coffee, or a whole
multiple or major fraction of a single standard serving. For
example, in some embodiments, the inventive coffee tablets may be
designed to produce whole multiples of a single standard serving,
e.g., to produce two standard servings of brewed coffee or three
standard servings. In other embodiments, the inventive coffee
tablets may be made larger, to produce more than a single serving
of coffee, and may be designed with surface scoring to allow a user
to preferentially break the tablets into smaller pre-designated
portions (i.e. break the tablet in half or into fourths, etc.), and
the individual portions could then be used to produce separate
coffee servings. In other embodiments, the inventive coffee tablets
may be designed to produce a major fraction of a standard single
serving such as 1/2 of a standard serving, or 1/3 of standard
serving, or 1/4 of standard serving. If so, the inventive coffee
tablets will contain a correspondingly greater or lesser amount of
ground roast coffee. This does not necessarily mean that using one
single coffee tablet designed to produce a single standard serving
in a standard automatic drip coffee maker will necessarily always
result in one single serving of acceptable brewed coffee. Many
standard automatic drip coffee makers are configured to make, at
minimum, more than one serving of coffee at a time, e.g., four (4)
servings of coffee at a minimum, and the inventive coffee tablets
are not necessarily able to overcome that limitation of such coffee
brewers. For such tablets designed to produce a single standard
serving of coffee, one would expect, for example, four of such
tablets to produce four servings of acceptable brewed coffee, five
of such tablets to produce five servings of acceptable brewed
coffee, seven of such tablets to produce seven servings of
acceptable brewed coffee, etc. For an automatic drip coffee maker
designed to brew one serving of coffee at a time, one may be
expected to use one tablet per serving. Of course, the consumer may
add or reduce these numbers to control strength of the brewed
coffee to match their particular taste preference (e.g., any one or
more or fewer tablets than this one-tablet-per-serving ratio, such
as five tablets to make four servings, six tablets to make four
servings, three tablets to make four servings, etc.).
[0063] As indicated above, different ground coffees exhibit
different densities depending on the type of coffee used, the
method by which the coffee is roasted, the color of the roasted
coffee, the particle size to which the coffee is ground, moisture
content, and other factors.
[0064] A typical ground roast coffee having a density of 0.33 g/cc
and a standard moisture content of about 1-7% requires
approximately 3 grams to produce a standard serving of brewed
coffee, both regular and espresso strength, at least in the United
States. Thus, the inventive ground roast coffee tablets, when
designed to produce one standard serving of brewed coffee per
tablet, will normally contain about 3.+-.1 grams of ground roast
coffee, based on a density of 0.33 g/cc and a standard moisture
content of about 1-7%, more typically about 3.+-.0.5 grams of
ground roast coffee. Exemplary inventive coffee tablets may have a
mass of less than about 4 grams, less than about 3.5 grams, less
than about 3.3 grams, less than about 2.7 grams, about 2.6 to 2.8
grams, or even a mass of about 1.9 grams to about 2.7 grams. Ground
roast coffees of greater or less densities, e.g., 0.288 g/cc, (and
greater or lesser moisture contents, as further discussed below)
require correspondingly less or greater amounts of coffee to
produce a standard serving of brewed coffee.
[0065] When a ground roast coffee having a density of 0.33 g/cc and
a standard moisture content of about 1-7% is used for producing a
single standard serving of coffee, approximately 3 grams of this
coffee will be required, as indicated above. This volume of ground
roast coffee will produce a generally cylindrical tablet measuring
approximately 25 mm in diameter and 6-7 mm in thickness when
compacted in a typical compaction process carried out in accordance
with this invention, as further described below. When coffees of
different densities and/or moisture contents are used,
correspondingly different tablet volumes will be achieved.
Similarly, inventive tablets made with different dose sizes, e.g.,
a tablet made to produce 1/3 of a standard serving of brewed coffee
per tablet, will also have correspondingly different sizes.
Different tablet configurations are also possible. For example,
oval, heart, "pillow" and other shapes are anticipated. Further, at
least one side of a generally cylindrical tablet may be concave.
Additionally or alternatively, the outer surface of a tablet may
have ridges, bumps, surface scoring, or embossments.
Packaging and Use
[0066] The inventive ground roast coffee tablets are intended to be
provided to the customer, both consumers and commercial/industrial
users, in suitable packages. Many types of packages and packaging
material can be used for this purpose including bags made from
plastic, paper, foil, cellophane or other suitable material; boxes
made from cardboard, rigid plastic, foamed plastic, etc.; bottles,
sleeves, etc. Combinations of these packages can also be used.
[0067] If desired, the inventive ground roast coffee tablets can be
packaged in specific numbers for making predetermined amounts of
coffee. For example, tablets designed to produce a single serving
of coffee per tablet can be packaged in groups of four to
facilitate making four cups of coffee in a single brew cycle.
Alternatively, groups of two or more tablets can be packaged
together to facilitate making a single serving of coffee in a
single brew cycle. For example, three tablets designed to produce
1/3 serving of coffee per tablet can be packaged in groups of three
to facilitate making a single serving of coffee in a single brew
cycle. The tablet packages can be designed to be resealable for the
convenience of the customer. In such a configuration, as the
tablets are periodically used by the consumer, the unused tablets
that remain could be resealed in the package to retain product
freshness.
[0068] A particular advantage of this invention is that, because
the inventive coffee tablets contain a predetermined amount and
type of ground roast coffee (and other optional ingredients),
adjusting dosages to achieve the precise flavor desired is made
much easier. For example, a consumer desiring to make a stronger
brewed coffee than normal can use five inventive coffee tablets (of
a single serving size) rather than four for brewing four servings
of brewed coffee. As another advantage, inventive coffee tablets
differing in one or more properties may be combined in the same
brew to produce a preferred brew in which the one or more
properties resulting from the combination of differing coffee
tablets provide a desired flavor, strength, caffeine content, or
other such characteristic in the preferred brew. For example, a
brewed coffee with a desired reduced caffeine content may be
prepared by combining at least one or a portion of one regular
caffeinated coffee tablet with at least one or a portion of one
decaffeinated coffee tablet in an ADC coffee maker. As another
example, a brewed coffee with a desired "darkness" of roast flavor
may be prepared by combining at least one or a portion of one dark
roasted coffee tablet with at least one or a portion of one regular
coffee tablet in an ADC coffee maker. In still another example, a
brewed coffee with a combination of special flavorings may be
prepared by combining at least one or a portion of one coffee
tablet having a first flavoring (for example, chocolate) with at
least one or a portion of one coffee tablet having a second
flavoring (for example, hazelnut) in an ADC coffee maker. In still
other embodiments, multiple properties may be varied or adjusted by
using coffee tablets differing in two or more properties. As one
specific example, a consumer desiring to make a brewed coffee
having a reduced caffeine content and a "hint" of French vanilla
flavor can use three inventive coffee tablets made from regular
ground roast coffee, two tablets made from decaffeinated coffee,
and one tablet of French vanilla flavored coffee. Further, some
coffee tablets may be provided with two or more varied properties,
such as, for example, dark roasted decaffeinated coffee tablets,
medium roasted decaffeinated coffee tablets, and dark roasted
regular coffee tablets. An exemplary consumer selected blend could
then include three dark roasted coffee tablets with five medium
roast decaffeinated coffee tablets and four cinnamon-flavored
coffee tablets.
[0069] In view of the above advantages, methods of brewing coffee
are contemplated comprising (a) placing at least one or a portion
of one of a first type of coffee tablet and at least one or a
portion of one of a second type of coffee tablet into an ADC coffee
maker and (b) actuating a brew cycle of the ADC coffee maker to
brew coffee with the coffee tablets or coffee tablet portions.
Variables that may be adjusted by selecting one or more tablets of
different types of ground roast coffee include, for example, amount
or type of flavorant, caffeine content, levels of acidity, darkness
of roast, species of coffee (e.g., Arabica, robusta), and
alternative coffee bean treatment (e.g., low moisture drying prior
to roasting). A wide variety of types of coffee tablets may be
provided together in a pre-packaged kit, or in a consumer selected
array, to facilitate preparation of a preferred brew specific to an
individual consumer's preferences. As such, an exemplary kit may
include a plurality of tablets, with at least two of the tablets
having a different predetermined property, such as, for example,
amount or type of flavorant, caffeine content, level of acidity,
darkness of roast, species of coffee, or type, of coffee bean
treatment. Such a kit may be provided with instructions for
combining the two or more types of coffee tablets to prepare a
desired brewed coffee. These instructions may include one or more
"recipes" for preparing one or more special predetermined blends of
coffee.
[0070] A further advantage of the inventive coffee tablets is that
they are smaller in size than conventional ground roast coffee on a
comparable basis, i.e., based on the same amount of coffee
provided. This allows the inventive coffee tablets to be marketed,
transported and sold in smaller packages, which in turn is
beneficial for the environment. Tablets with a volume less than 3.2
cm.sup.3, less than 2.9 cm.sup.3, and less than 2.3 cm.sup.3 are of
particular interest.
[0071] In use, the appropriate number of tablets will be removed
from their package(s), manually placed in the brew basket of an
automatic drip coffee maker, and then brewed into brewed coffee in
the normal way.
Tablet Manufacture
[0072] In accordance with this invention, the inventive ground
roast coffee tablets are made in such a way that they disintegrate
essentially immediately (or at least very rapidly) when contacted
with hot brewing water at the beginning of the brewing cycle, as
indicated above. In addition, they are also made to resist
significant degradation from the manual handling they receive
during manufacture and use. In particular, the inventive coffee
tablets are made to have sufficient hardness and friability before
brewing to withstand all aspects of manufacture, handling,
packaging, transport and use without breakage to any significant
degree.
[0073] This is accomplished in accordance with this invention by
making the inventive ground roast coffee tablets by multi-step
compaction, i.e., by compressing ground roast coffee into shaped
articles by a multi-step compaction process carried out in the same
compaction die in which the ground roast coffee is compressed at a
first compaction pressure and then subsequently further compressed
at least one more time in the same compaction die. Many of the
tablets herein discussed were made in multi-step compaction process
carried out in the same compaction die in which the ground roast
coffee is pre-compressed at a relatively lower compaction pressure
and then subsequently further compressed at a relatively higher
pressure in a main or primary compaction step. In accordance with
this invention, it has been found that this approach allows
stronger tablets to be produced than would otherwise by the case if
an otherwise identical tablet having an otherwise identical density
were made by a single-step compaction process. That is to say,
coffee tablets made by the inventive multi-step compaction process
are stronger (as measured by hardness, friability or both, as
further discussed below) than otherwise identical tablets having
the same density but made by a conventional single-step compaction
process. In the alternative, tablets can be made using a multi-step
compaction process carried out in the same compaction die in which
the ground roast coffee is compressed at a relatively higher
compaction pressure initially and then subsequently further
compressed at a relatively lower pressure in a separate compaction
step. This second approach may be problematic for some machines,
because they use a measured highest compaction force or pressure to
control how much material is deposited into the die (with a higher
than desired force indicating that too much material has been
deposited) and controlling based on a higher pre-compression may be
less accurate than controlling based on a higher main compression.
Although many of the examples herein are carried out with a
relatively lower compaction pressure initially and then
subsequently further compressed at a relatively higher pressure in
a separate compaction step, and much of the teachings herein are in
this context, it is to be understood that many of the advantages
taught herein can be obtained using three or more total compactions
in the same die and/or a relatively higher compaction pressure at
other than the final compression step, and the virtually any of the
methods herein can be thought of as being capable of being carried
out using three or more total compactions in the same die and/or a
relatively higher compaction pressure at other than the final
compression step (e.g., first or second or third non-final
compression).
[0074] Although the inventive multi-step compaction process will
normally be carried out with two compaction steps, one, two, three
or more additional, intermediate compaction steps can also be used,
usually at compaction pressures between the compaction pressures
encountered in the pre-compression and main compression steps.
However, greater or lesser compaction pressures can also be used in
the intermediate compaction steps, if desired.
[0075] Compressive or compaction forces on the order of .about.25
to .about.80 kN (kiloNewtons), .about.35 to .about.65 kN, or even
.about.40 to .about.50 kN have been found suitable for the main
compression step (based on tablets having diameters of .about.24 mm
to .about.25 mm). Thus, these main compressive forces will normally
be >.about.25 kN, >.about.35 kN, >.about.40 kN, and, in
addition, generally <.about.80 kN, <.about.55 kN, or even
<.about.50 kN. Expressed as applied pressure during compaction
(assuming a 24.5 mm tablet diameter), the corresponding
compressions would be >.about.53.0 MPa (or N/mm.sup.2),
>.about.74.2 MPa, >.about.84.8 MPa, and, in addition,
generally <.about.169.6 MPa, <.about.116.7 MPa, or even
<.about.106.1 MPa. Greater or lesser compressive forces can be
used depending on the type, particle size and other properties of
the ground roast coffee being processed, the desired density,
strength and hardness of the coffee tablet being produced, and
certain production variables as further discussed below, and can
easily be determined by routine experimentation based on the
teachings herein.
[0076] A number of processes are known for forming tablets and
other shaped articles from granular materials by compression. Most
such processes require (1) filling a die, typically closed off at
the bottom by a bottom tool, with the material to be tabletted (2)
compressing the filled material between upper and lower tools, and
(3) ejecting the tablet so formed from the die.
[0077] Presses may be single station or multiple station. In this
context, a "station" refers to a single die and its associated top
and bottom tools. In a single station press, a single stationary
die is used, and all functions (e.g., filling, compression and
ejection) occur in the same location. In a multiple station press
such as a rotary tablet press, multiple sets of dies and their
associated top and bottom tools are moved from location to location
where the separate functions of filling, pre-compression, main
compression and ejection occur.
[0078] For example, a typical rotary table press has a turret
containing a die table formed from multiple die stations. The
turret containing the die table rotates through the press so that
each die is serially brought to the different filling, pressing and
ejection locations in the press. Dies are filled at the filling
location, the material to be tabletted compacted in the
pre-compression and main compression locations, and the tablet
formed thereby ejected from the die at the ejection location.
Actuation of the top and/or bottom tools for compressing the
material to be compacted in the pre-compression and main
compression locations can be done in a variety of different ways,
including using cams, ramps, compression rollers or combinations
thereof, all of which are designed to force the bottom and top
tools associated with each die together. The size of the
compression rollers or other tool compressing mechanisms may limit
the proximity of the pre-compression and main compression
locations, which may, for example, be separated by approximately
1/4 of the die circle circumference. While the coffee material may
be under compression during this delay period, in one embodiment,
the die tools may be held in proximity to the compression positions
without exerting additional compaction forces, for example, by
holding the tools using tracks, ramps, or other mechanisms provided
with the rotary tablet press. This delay between pre-compression
and main compression steps may have a duration of approximately
80-900 milliseconds, or 150-400 milliseconds, or 200-290
milliseconds, under normal rotary tablet press operating speeds
(e.g., 15-60 rpm), or about 15-23 times either of the
pre-compression and/or the main compression dwell times. Therefore,
while each of the pre-compression and main compression steps may be
very brief (for example, pre-compression and main compression dwell
times ranging from 7-45 milliseconds), the total time from the
start of the pre-compression step to the completion of the main
compression step may be 8-15 times the total time under compression
at the pre-compression and main compression rollers. This total
compression time may be, for example, approximately 0.1 to 1
second, approximately 0.18 to 0.5 seconds, or 0.22 to 0.36 seconds.
As such, even minor adjustments to the dwell times of the
pre-compression and main compression steps may result in
significant changes to the tablet production rates, as adjustments
to the rotary press operating speed are generally proportional to
these dwell time adjustments.
[0079] In a typical rotary press, each die is subjected to one set
of compressions, for production of one table, per die, in a single,
360.degree. revolution of the turret. In other rotary presses,
additional filling, compression and ejection locations may be
provided for production of two or more tablets, per die, in a
single 360.degree. revolution of the turret. While pre-compression
locations have been included in typical rotary tablet presses, the
amount of pre-compression forces applied during prior art
tabletting has generally been minimal, the purpose of which being
to force or squeeze pockets of air out of the powder to be
tabletted, to prevent voids or fractures in the resulting
tablet.
[0080] Generally speaking, longer compression dwell times require
less compression force in the main or primary compression step.
Some increases in dwell time may be accomplished by increasing the
size of the portions of the tools impacted by the compression
rollers or other compression mechanism, often referred to as the
tool heads. However, more substantial increases in compression
dwell time typically require slower machine operating speeds, such
that the top and bottom tools are aligned with the compression
rollers (or other compression mechanism) for the desired dwell time
period. As such, a substantially longer dwell time for compaction
of the tablet generally limits the tablet production rate by
requiring a substantially slower machine operating speed, thereby
slowing down other steps of the tabletting process (e.g., filling,
pre-compression, or ejection of completed tablet).
[0081] As further indicated above, the compressive forces used for
a particular application of this invention also depend on the
desired properties of the inventive ground roast coffee tablets to
be produced. In this regard, it has been found that, within certain
limits, greater compressive forces lead to stronger tablets, and
conversely, lesser or reduced compressive forces lead to weaker
tablets. On the other hand, compressive forces which are too high
can weaken the tablet. Indeed, reliance on increases in compressive
forces alone, without regard to dwell time, amount of
pre-compression, or other such factors, may be insufficient to
produce tablets of desired strength, as shown, for example, in the
working examples (see, e.g., Example 14).
[0082] The strength/robustness of the ground roast coffee tablets
of this invention can conveniently be measured in several ways, two
examples of which include measuring a tablet's hardness and
friability. Hardness measures the force required to break the
tablet in an axial direction. Tablet hardness can be determined by
a diametral compression test in which the tablet is placed between
two anvils and a pressure is applied to the anvils until the tablet
breaks. The crushing strength that just causes the tablet to break
is taken as the hardness of the tablet, which is sometimes referred
to as the "tablet crushing strength." The hardness of an article
can be determined using any number of devices and techniques known
to skilled coffee professionals, including, for example, the Stokes
(Monsanto) tester, the Strong-Cobb tester, the Pfizer tester, the
Erweka tester, the Heberlein (or Schleuniger) tester, the Key
tester, the Varian VK200 Tablet Hardness tester, and the Van der
Kamp tester, and the techniques associated with each of these
devices. In accordance with this invention, the inventive ground
roast coffee tablets are normally made to have a hardness of
.gtoreq..about.30 N (Newtons), when measured using a Varian VK200
Tablet Hardness tester set in the N (Newton) mode. Hardnesses on
the order of .gtoreq..about.40 N, or .gtoreq..about.50 N, are even
more interesting, while hardnesses of .gtoreq..about.60 N,
.gtoreq..about.70 N, .gtoreq..about.80 N, .gtoreq..about.90 N,
.gtoreq..about.100 N, and even .gtoreq..about.110 N and more are
possible.
[0083] Friability measures the amount of material that flakes,
falls, or chips off the tablets after being tumbled under a
predetermined set of conditions. For convenience, the friability of
the inventive coffee tablets can be measured using a
commercially-available Varian Friabilator having a dual chamber
friability drum by rotating 25 grams of the tablets in the drum of
the machine for 100 revolutions at a rate of 25 rpm and then
determining the amount of these tablets that passes through a #4
American Standard Wire Mesh screen. The tablets should not be
broken to obtain 25 grams, but adjust the number of whole tablets
to come as close as possible to 25 grams. The weight of material
passing through this screen in proportion to the total weight of
the original charge of tablets represents the friability of these
tablets. In accordance with this invention, it has been found that
the inventive coffee tablets, when made in the manner indicated
above, may have a friability of <.about.10%, <.about.8%,
<.about.6%, <.about.3.5%, <.about.3%, or even
<.about.1%.
[0084] Generally speaking, coffee tablets having the above
combination of properties, i.e., a hardness of at least about 30 N
(Newtons) and a friability of less than about 10%, will have a
density on the order of .gtoreq.0.85 g/cm.sup.3, .gtoreq.0.87
g/cm.sup.3, .gtoreq.0.90 g/cm.sup.3, .gtoreq.0.92 g/cm.sup.3,
.gtoreq.0.95 g/cm.sup.3, .gtoreq.0.97 g/cm.sup.3, and even
.gtoreq.0.99 g/cm.sup.3. Coffee tablets having densities of
.gtoreq.0.90 g/cm.sup.3, .gtoreq.0.92 g/cm.sup.3, .gtoreq.0.95
g/cm.sup.3, .gtoreq.0.97 g/cm.sup.3, and even .gtoreq.0.99
g/cm.sup.3 are especially interesting.
[0085] An external coating can enhance the tablet strength,
allowing tabletting at a reduced compaction force. Any material
described above as useful for making a binder to be included in the
inventive coffee tablets can be used for making such coatings.
[0086] In accordance with this invention, the inventive ground
roast coffee tablets are made to have the above properties by using
a multi-step compaction process comprising two or more compression
steps, a pre-compression step, a main or primary compression step,
and optionally, one or more intermediate compression steps, all of
which are carried out in the same die. In other words, once the
ground roast coffee is filled into a particular compaction die, it
is subjected to all of the compactions steps need to produce a
completed coffee tablet in that same die before being ejected
therefrom. In general, this approach allows lower compression
forces to be used in the main compression step, which in turn
places less stress on the press. In addition, this approach also
allows for reduced compression dwell times, as compared to the
extended dwell times generally associated with lower compression
forces, which enables faster press operation. Finally, as indicated
above, this approach also allows stronger tablets to be produced
(for a given tablet density) than otherwise identical tablets made
by a single-step compaction process.
[0087] When using this approach, the pre-compression force is
desirably at least about 5 kN (based on tablets having diameters of
.about.24 mm to .about.25 mm), or about a 10.6 MPa pre-compression
pressure (for a 24.5 mm diameter tablet). A pre-compression force
this low may require the use of a binder or a liquid flavor carrier
with binder properties to provide tablets with acceptable
friability and hardness at relatively high manufacture rates per
die (as suggested by the data below, use of some binders or liquid
flavor carriers with binder properties might also permit tablets
made with a single compression to obtain acceptable friability and
hardness at relatively high manufacture rates per die).
[0088] Additionally, compressive forces on the order of .about.25
kN, .about.35 kN, .about.12 to .about.40 kN, .about.18 to .about.35
kN, or even .about.25 to .about.35 kN have been found suitable for
this pre-compression step (based on tablets having diameters of
.about.24 mm to .about.25 mm). Thus, these pre-compressive forces
will normally be .about.25 kN, .about.30 kN, or >.about.12 kN,
>.about.17 kN, >.about.18 kN, >.about.20 kN, >.about.25
kN, >.about.35 kN and, in addition, generally <.about.40 kN,
<.about.35 kN, or even <.about.30 kN. Expressed as applied
pressure during compaction (assuming a 24.5 mm tablet diameter),
the corresponding pre-compressions would be .about.53.0 MPa (or
N/mm.sup.2), .about.63.6 MPa, or >.about.25.5 MPa,
>.about.36.1 MPa, >.about.38.2 MPa, >.about.42.4 MPa,
>.about.53.0 MPa, >.about.74.2 MPa and, in addition,
generally <.about.84.8 MPa, <.about.74.2 MPa, or even
<.about.63.6 MPa. Expressed as a percentage of main compression
force, pre-compressive forces of about 20-100%, 30-90%, 40-80%, or
even 50-75% of main compression force have been found suitable for
the pre-compression step (based on tablets having diameters of
.about.24 mm to .about.25 mm). Thus, these pre-compressive forces
will normally be >.about.20%, >.about.30%, or >.about.40%
and, in addition, generally <.about.100%, <.about.90%, or
even <.about.80% of the main compression force. Greater or
lesser compressive forces can be used depending on the type,
particle size and other properties of the ground roast coffee being
processed, the desired density, strength and hardness of the coffee
tablet being produced, and certain production variables as further
discussed below, and can easily be determined by routine
experimentation based on the teachings herein.
[0089] In this regard, FIG. 1 shows the effect of altering the
pre-compression force on the hardness, friability and extraction
efficiency of the inventive ground roast coffee tablets obtained.
This figure was developed from experiments in which a group of
coffee tablets was produced by a two-step compaction process in
which the tablet was first subjected to a pre-compression force
ranging from .about.0.3 kN to .about.50 kN and thereafter subjected
to a main compression force in the same compression die ranging
from .about.10 to .about.70 kN. The data in FIG. 1 has been
normalized to values observed with very low/no initial compression
being taken as equal to 1. As shown in FIG. 1, when the
pre-compression force used to make the inventive coffee tablets is
varied between .about.20% to .about.100% of the main compression
force, the hardness of the tablets produced increases by as much as
40% (at a pre-compression/main compression ratio of about 0.70),
while the friability of the tablets produced is reduced by as much
as 80% (at a pre-compression/main compression ratio of about 0.55).
This makes it possible in accordance with this aspect of the
invention to design the inventive coffee tablets having a
predetermined combination of hardness and friability, as
desired.
[0090] As indicated above, one advantage of using the inventive
multi-step compaction process for manufacturing the inventive
coffee tablets, at least when this is done using a multiple station
press, is that press operation is faster than would otherwise be
the case if a single step compaction process were used. This is
made possible because less compaction force can be used in the main
or primary compaction step than would be required if compaction
occurred in a single compaction step. In addition, using a multiple
compaction steps allows the dwell time needed in the primary or
main compactions step, i.e., the amount of time the ground roast
coffee remains under compaction, to be less than that required if
only a single compaction step were used.
[0091] In this regard, see WO 2008/107342, which makes clear that
in order to make a ground roast coffee tablet of sufficient
strength using single step compaction (in which pre-compression is
minimal or non-existent), the ground roast coffee must be
compressed at a fairly slow rate (i.e., over the course of 0.1 to 2
seconds, preferably 0.2 to 0.8 seconds) and then held at its final
volume for an additional significant period of time (i.e., for 0.2
to 5 second, preferably 0.3 to 2 seconds, and even more preferably
0.5 to 1.5 seconds). In contrast, the inventive process described
herein uses a multi-step compaction approach that does not employ
slow compression and an extended dwell time at final volume. In
accordance with this invention, it has been found that
pre-compression "prepares" the ground coffee for final compaction
in such a way that less compaction pressure for a shorter period of
time is necessary to produce a fully compacted tablet. This
pre-compression preparation of the ground coffee, combined with a
desired main compaction of the coffee tablet, as provided for in
the production of the inventive coffee tablets, is believed to
strike a balance between a number of factors believed to have an
impact on the physical properties and the brew performance of the
tablets, including, for example, tablet strength/robustness, tablet
density, table porosity (including the degree of hydrophobicity,
the diameter, the length, and/or the orientation of channels and
passages on the surface of and within the body of tablet), particle
sizes of the coffee from which the tablets are composed, water
permeability, and water vapor permeability. When brewed in certain
coffee makers where the tablets are exposed to steam during the
brewing process (e.g.: automatic drip coffee makers), the water
vapor permeability is believed to play a significant role in brew
performance.
[0092] Thus, in accordance with this aspect of the invention, the
inventive multi-step compaction process is carried out in such a
way that the dwell time of the ground roasted coffee in the main
compaction step, i.e., the period of time in which the coffee is
under active compression in the main compaction step, is
.ltoreq..about.0.3 second, .ltoreq..about.0.25 second,
.ltoreq..about.0.2 second, .ltoreq..about.0.15 second, or even
.ltoreq..about.0.1 second. Indeed, dwell times on the order of
.ltoreq.75 milliseconds, .ltoreq.50 milliseconds, .ltoreq.25
milliseconds, .ltoreq.20 milliseconds, and even .ltoreq.15
milliseconds are contemplated and shown in the following working
examples.
[0093] For an exemplary rotary tablet press, the pre-compression
and main compression dwell times may be determined from a known
rotational speed of the rotary press and the fraction of the die
revolution for which the head flat (i.e. the portion of the tool
that contacts the compression roller, ramp, or cam) is held for
pre-compression or compression by the compression roller, ramp, or
cam. Where the compression location on the rotary press is limited
to a discrete, instantaneous location (as is the case with tools
impacted by compression rollers), this fraction of the die
revolution is approximately equal to the tool head diameter divided
by the die circle circumference. Thus, dwell time (in milliseconds)
in such applications may be calculated as: [(Head Flat
Diameter)/(2.pi..times.(Radius of rotary press die
circle))].times.[(60,000 ms/min)/(RPM)]. As one example, a
29-station rotary press with a die circle diameter of 410 mm and a
head flat diameter of 15.52 mm can produce 90,000 tablets per hour
using an operating speed of approximately 51.7 rpm, resulting in
pre-compression and main compression dwell times of approximately
14 ms each.
[0094] Because this dwell time is the rate limiting step in the
operation of multi-station presses, press operation can be much
faster when the inventive multi-step compaction process is used.
Thus, commercially-available multi-stage tabletting presses can be
operated at machine speeds capable of producing .gtoreq.50,000,
.gtoreq.75,000, .gtoreq.100,000, and even .gtoreq.125,000,
inventive coffee tablets per hour using the inventive processes.
Because different machines may have two or more distinct production
lines (two or more main compression steps), which may differ from
machine to machine, it may be helpful to set forth production rates
in terms of a number of tablets per set of compressions per die per
hour (e.g., for the pre-compression/main compression examples, the
set of compressions would include both compressions). Using the
inventive processes to manufacture the inventive tablets herein,
production rates of >1000 tablets per set of compressions per
die per hour; >1500 tablets per set of compressions per die per
hour; >2000 tablets per set of compressions per die per hour;
>2400 tablets per set of compressions per die per hour; >2500
tablets per set of compressions per die per hour; >2750 tablets
per set of compressions per die per hour; and >3000 tablets per
set of compressions per die per hour are possible, and even
production rates of >3100 tablets per set of compressions per
die per hour; >3450 tablets per set of compressions per die per
hour; and >3500 tablets per set of compressions per die per hour
are possible.
[0095] Tabletting presses capable of carrying out multi-stage
compaction at these compaction pressures, dwell times, and
production rates are available from a number of different
commercial sources including Fette.RTM., Korsch.RTM., and possibly
Courtoy.RTM. and Manesty.RTM..
[0096] In accordance with still another feature of this invention,
it has been further found that the inventive coffee tablets,
because of the way they are made, achieve a greater total
extraction of coffee solids during brewing as compared to an
otherwise identical conventional ground roast coffee composition
(i.e., the same untabletted ground roast coffee). That is to say,
the total amount of coffee solids extracted and recovered in the
brewed coffee product obtained is greater when the inventive coffee
tablets are used in a typical ADC coffee maker than when the same
amount of conventional (untabletted) ground roast coffee is used in
the same coffee maker.
[0097] This feature is illustrated in the following working
examples which show that the yield ratios provided by the inventive
coffee tablets, i.e., the ratio of the coffee solids recovered from
brewing the inventive coffee tablets relative to the coffee solids
recovered from brewing a substantially equal amount of untabletted
(but otherwise identical) ground roast coffee, are normally >1
and in many instances >1.1, >1.15, and even >1.2 on a
weight basis. Moreover, this is so even when the yield of coffee
solids, i.e., the ratio of the coffee solids recovered from brewing
the inventive coffee tablets relative to the amount of coffee
present in the coffee tablets before brewing (i.e., [grams of
coffee solids extracted from the brewed coffee]/[grams of coffee
placed in the brew basket to brew the coffee].times.[100]), is
>26%, >28.5%, or even >30%.
[0098] Still another feature of this invention is that an enhanced
extraction efficiency (as evidenced, for example, by increased
absorbance, absorbance per gram, yield, and percent brew solids)
exhibited by the inventive coffee tablets, as described herein, is
essentially independent of the magnitude of the pre-compression
force used in the pre-compression step of the inventive
manufacturing process. This is illustrated in FIG. 1, which further
shows that the brew solids (i.e., amount of coffee solids recovered
in the brewed coffee product) remains essentially unaffected as the
magnitude of the pre-compression force is varied. (When using an
automatic drip coffee maker having a water delivery rate of
approximately 2.5-3.1 g/sec, brew solids of 0.36-1.3% or 0.5-1% or
0.42-1.5% or 0.5-0.9% or 0.50-0.75% are of interest.) Because of
this feature, the hardness and friability of the inventive coffee
tablets can be suitably selected, as discussed above, without
compromising this enhanced brewing efficiency.
[0099] Another way to determine the amount of coffee solids that
are extracted during brewing is to measure the coffee brew's
absorbance. The absorbance is, in effect, a measure of the darkness
of a coffee brew. A spectrophotometer is used to measure the amount
of light absorbance by the liquid brewed coffee at a wavelength of
480 nanometers (nm). A wavelength of 480 nm has been chosen because
it corresponds with an absorption feature in the visible spectrum
that is associated with the brown color of coffee brews (i.e., the
Brown Color absorbance). Stronger coffee brews typically exhibit a
bore prominent Brown Color absorbance. Thus, the absorbance value
taken at 480 nm correlates with the visually perceived darkness of
a cup of coffee. In practice, for example, a sample of brewed
coffee is placed in an 8 ml sealed vial and cooled for 15 minutes
at room temperature; the sample is then transferred to a cuvette
and the absorbance is measured in a Genesys 10 Spectrophotometer at
480 nm wavelength. Absorbance values>1.1, >1.25, and >1.7
and <3.5, <2.5, and <1.75 are of interest. From this base
measure of the brewed coffee absorbance, several other values are
of interest, including: absorbance ratio (absorbance of brew from
tablets/absorbance of brew of the same untabletted ground roast
coffee); absorbance per gram (absorbance/grams of coffee put in
brew basket) (e.g., at a 10 tablet basis); and absorbance/gram
ratio: (Absorbance/gram tablets)/(Absorbance/gram of the same
untabletted ground roast coffee). Absorbance ratios>1, >1.06,
and >1.12 are of interest. Absorbance per gram values>0.06,
>0.07, and >0.09 are of interest. Absorbance per gram
ratios>1.05, >1.15, and >1.2 are of interest.
Brew Dynamics
[0100] In accordance with still another aspect of this invention,
it has further been found that the inventive coffee tablets, which,
because of the way they are made, may have a modified time
dependency associated with their brew performance over the course
of brewing cycle (also referred to as "brew dynamics"). For
example, over the duration of a brew cycle, the instantaneous
concentration of coffee solids extracted (herein referred to as
"instantaneous extracted coffee solids concentration") for a
particular chronological portion of the brew (for example, one or
more aliquots forming an initial, a middle, or an end portion of
the brew) may be altered, as compared to the instantaneous
extracted coffee solids concentration for the same portion formed
from one or more aliquots taken from a brew made using untabletted
coffee in roasted and ground form. As described herein, an
"instantaneous" measure of brew dynamics (e.g., instantaneous
concentration, instantaneous absorbance, or instantaneous brew
delivery) describes the characteristics of one of a series of
incremental or sequential samples or aliquots taken
contemporaneously with the brewing process, such as, for example,
one of a series of 20 second timed aliquots of the brew.
[0101] Thus, in accordance with this aspect of the invention, the
instantaneous extracted coffee solids concentration associated with
an initial portion of a brew produced using the inventive coffee
tablets may be lower than the instantaneous extracted coffee solids
concentration for an initial portion of a brew produced using the
corresponding untabletted coffee. The extent to which the
concentration of solids will be lower may depend, for example, on
the wettability of the compacted coffee tablet and the rate at
which the coffee tablet is broken up during brewing. Expressed in
terms of the mass of the total brew, in one example using an
automatic drip coffee maker having a water delivery rate of
approximately 2.5-3.1 g/sec, the mass of the initial portion is
approximately 200-300 g taken from a total brew mass of 1330 g.
Expressed in terms of the total brewing period, in one example
using an automatic drip coffee maker having a water delivery rate
of approximately 2.5-3.1 g/sec, this initial portion is removed,
approximately, during the initial 100-150 seconds of a 630 second
total brew period (as timed from initial extraction).
[0102] Additionally or alternatively, in accordance with this
aspect of the invention, the instantaneous extracted coffee solids
concentration associated with a middle portion (collected in one or
more aliquots) of a brew (e.g., during a period immediately
following the period associated with the initial portion) produced
using the inventive coffee tablets may be greater than the
instantaneous extracted coffee solids concentration for a middle
portion of a brew produced using the corresponding untabletted
coffee. The extent to which the concentration of solids will be
higher with the inventive coffee tablets may depend, for example,
on an increased extractability be associated with or resulting from
the disruption of cellular particles within the coffee tablets.
Expressed in terms of the mass of the total brew, in one example
using an automatic drip coffee maker having a water delivery rate
of approximately 2.5-3.1 g/sec, the mass of the middle portion is
approximately 200-300 g taken immediately following the initial
200-300 g associated with the initial portion, from a total brew
mass of 1330 g. Expressed in terms of the total brewing period, in
one example using an automatic drip coffee maker having a water
delivery rate of approximately 2.5-3.1 g/sec, this middle portion
is removed, approximately, during the 80-130 seconds, immediately
following the 100-150 seconds in which the initial portion is
taken, of a 630 second total brew period (as timed from initial
extraction).
[0103] A reduced instantaneous extracted coffee solids
concentration exhibited in the initial aliquot, as provided by
certain ones of the inventive coffee tablets, may be expressed as
the amount of coffee solids extracted during the initial brew
period, as a percentage of the total extracted coffee solids during
the entire brew. In one example using an automatic drip coffee
maker having a water delivery rate of approximately 2.5-3.1 g/sec,
the coffee solids extracted during the first 200 g of a 1330 g brew
is approximately 5-15% of the total coffee solids extracted during
the entire brew, and may, for example, be approximately 5-11% of
the total coffee solids extracted during the entire brew (as
compared to approximately 30-60% solids extraction for a
corresponding roast and ground coffee).
[0104] An increased instantaneous extracted coffee solids
concentration exhibited in the middle portion, as provided by
certain ones of the inventive coffee tablets, may be expressed as
the amount of coffee solids extracted during the mid-range brew
period (during which the one or more aliquots taken to form the
middle portion of the brew are collected), as a percentage of the
total extracted coffee solids during the entire brew. In one
example using an automatic drip coffee maker having a water
delivery rate of approximately 2.5-3.1 g/sec, the coffee solids
extracted during the 250 g after the first 250 g of a 1330 g brew
is approximately 35-50% of the total extracted coffee solids during
the entire brew, and may, for example, be approximately 40-50% of
the total coffee solids extracted during the entire brew (as
compared to approximately 20-40% solids extraction for a
corresponding roast and ground coffee). In another example using an
automatic drip coffee maker having a water delivery rate of
approximately 2.5-3.1 g/sec, the coffee solids extracted during the
200 g after the first 300 g of a 1330 g brew is approximately
33-40% of the total coffee solids extracted during the entire brew
(as compared to approximately 15-27% solids extraction for a
corresponding roast and ground coffee).
[0105] A reduced instantaneous extracted coffee solids
concentration measured during an initial brew period, followed by
an increased instantaneous extracted coffee solids concentration
measured during a subsequent mid-range brew period, as provided by
certain ones of the inventive coffee tablets, may be expressed as a
ratio of the total coffee solids extracted during the initial brew
period divided by the total coffee solids extracted during the
mid-range brew period (or vice versa). As one example using an
automatic drip coffee maker having a water delivery rate of
approximately 2.5-3.1 g/sec, a ratio of the total coffee solids
extracted during the first 250 g of a 1330 g brew to the total
coffee solids extracted during the next 250 g of the brew is
approximately 0.3-0.65 (as compared to a corresponding roast and
ground coffee ratio of approximately 2-5). As another example using
an automatic drip coffee maker having a water delivery rate of
approximately 2.5-3.1 g/sec, a ratio of the total coffee solids
extracted during the first 200 g of a 1330 g brew to the total
coffee solids extracted during the 200 g after the first 300 g of
the brew is approximately 0.18-0.31 (as compared to a corresponding
roast and ground coffee ratio of approximately 1.4-3.5). As still
another example using an automatic drip coffee maker having a water
delivery rate of approximately 2.5-3.1 g/sec, a ratio of the total
coffee solids extracted during the first 200 g of a 1330 g brew to
the total coffee solids extracted during the 250 g after the first
250 g of the brew is approximately 0.14-0.25 (as compared to a
corresponding roast and ground coffee ratio of approximately
1.0-2.2).
[0106] Further, the brew dynamics of the inventive tabletted coffee
product may be such that after some intermediate point in the
brewing process (e.g., after an initial approximately 600-850 g of
a 1330 g brew) using an automatic drip coffee maker having a water
delivery rate of approximately 2.5-3.1 g/sec, the cumulative mass
of coffee solids extracted exceeds the cumulative mass of coffee
solids extracted from brewing the same untabletted coffee in
roasted and ground form at a corresponding point in its brewing
process. In one such example, this intermediate point is
approximately 300-360 seconds into a 630-second total brewing
period.
[0107] Additionally or alternatively, the inventive coffee tablets,
when brewed, may result in absorbance during an initial portion of
the brew that is lower than that produced during the same initial
portion of a brew when brewing the corresponding untabletted
coffee. A reduced absorbance during an initial brew period,
followed by an increased absorbance during a subsequent mid-range
brew period, as provided by certain ones of the inventive coffee
tablets, may be expressed as a ratio of the absorbance of the brew
during the initial brew period divided by the absorbance of the
brew during the mid-range brew period (or vice versa). As one
example using an automatic drip coffee maker having a water
delivery rate of approximately 2.5-3.1 g/sec, a ratio of the
absorbance during the first 250 g of a 1330 g brew to the
absorbance during the next 250 g of the brew is approximately
0.3-0.6 (as compared to a corresponding roast and ground coffee
ratio of approximately 1.5-2.5).
Instant Coffee
[0108] In accordance with another aspect of this invention, it has
been found that instant coffee when included in the inventive
coffee tablets in small but suitable amounts acts as a binder, a
disintegration aid and a brewing aid.
[0109] Coffee tablets formed entirely from instant coffee have been
made but such products typically do not have the desired flavor and
aroma characteristics of conventional ground roast coffee. Instant
coffee, however, can be mixed with ground roast coffee at low
levels and tabletted in accordance with the teachings herein.
[0110] The amount of instant coffee that may be included in the
inventive ground roast coffee tablets in accordance with this
aspect of the invention should be enough to achieve a noticeable
improvement in at least one of the properties indicated above,
i.e., binding strength, ease of disintegration and/or brewing
efficiency, without unduly altering the flavor of the coffee brew
produced. In general, this means that the amount of instant coffee
included will normally be .gtoreq..about.0.5 wt. %,
.gtoreq..about.1 wt. % or .gtoreq..about.3 wt. %, based on the
total amount of coffee solids in the tablet (i.e., the total amount
of ground roast coffee, decaffeinated ground roast coffee and
instant coffee). In addition, this also means that the amount of
instant coffee included will normally be .ltoreq..about.15 wt. %,
more typically .ltoreq..about.10 wt. %, or .ltoreq..about.6 wt. %,
.ltoreq..about.5 wt. % or even .ltoreq..about.4 wt. %, based on the
total amount of coffee solids in the tablet (i.e., the total amount
of ground roast coffee, decaffeinated ground roast coffee and
instant coffee). Embodiments in which the inventive coffee tablets
contain up to 20 wt. % or even 30 wt. % instant coffee are
contemplated.
[0111] The presence of instant coffee in coffee tablets can be
detected by a number of different methods. The process of making
instant coffee changes the composition of the coffee. One
compositional change that occurs is a change in the concentration
of low molecular weight carbohydrates that are present. Compounds
that tend to be increased in instant coffees are monosaccharides,
especially the monosaccharides mannose, arabinose, and galactose.
These may be measured by a variety of methods. However, one method
is described in R. M. Noyes and C. M. Chu, "Material Balance on
Free Sugars in the Production of Instant Coffee", ASIC, 15.sup.th
Colloque, Montpellier, 1993, which is incorporated herein by
reference. These three compounds increase in instant coffee
compared to roast ground coffee. Galactose is especially
interesting because previous reports have indicated that galactose
is not present in roast ground coffee. The other monosaccharides
may be present in ground roast coffee, but it is believed that they
are present at much lower levels than they are in instant coffee.
These differences in the amount of low molecular weight
carbohydrates present in tablets made from mixtures of roast ground
coffee and instant coffee do not affect the flavor of the coffee
brew produced, as long as the weight percent of instant coffee
present in the tablets is kept within the ranges described herein.
Interesting levels of these specific carbohydrates in certain
embodiments of the coffee tablets include: galactose in an
amount>0.0005 wt. %, or >0.001 wt. %, or >0.003 wt. %;
galactose in an amount<0.012 wt. %, or <0.02 wt. %, or
<0.03 wt. %; arabinose in an amount>0.0045 wt. %, or
>0.005 wt. %, or >0.0075; arabinose in an amount<0.04 wt.
%, or <0.07 wt. %, or <0.1 wt. %; mannose in an
amount>0.007 wt. %, or >0.0075 wt. %, or >0.008 wt. %; and
mannose in an amount<0.03 wt. %, or <0.04 wt. %, or <0.06
wt. %. These may be determined using a gas chromatograph as
follows: samples are freeze dried to remove water prior to the
analysis; samples are processed with dimethyl sulfoxide to
solubilize the sugars and the solution is silated with tri-sil
concentrate, which causes the free sugars to form a volatile
complex which is analyzed by direct injection into a gas
chromatograph. The percent relative standard deviation for this
method has been determined to be 2.52% for mannitol and 1.49% for
total free sugars.
[0112] Additionally, although not tested, the differences in
visible appearance and the hygroscopic nature of instant coffee
might permit the presence of instant coffee in a coffee tablet to
be detected by a visual inspection, especially if observed under a
microscope. For example, the addition of small amounts of steam to
roast ground coffee will not greatly affect the roast ground coffee
appearance (perhaps it will darken). In contrast, instant coffee is
known to absorb steam and may appear to liquefy and perhaps "melt."
This visual effect will likely be more pronounced if the tablets
being tested are broken up before being steamed and viewed under a
microscope. In addition, the visual inspection of a tablet under a
microscope without steaming might permit a determination that
instant coffee is present in the coffee tablet. This is because
instant coffee is known to have a very different appearance than
ground roast coffee. This different appearance may or may not be
easy to detect with tablets formed from both ground roast coffee
and instant coffee, as the tabletting process may change the size
of the particles making the difference between instant coffee
particles and ground roast coffee particles harder to see.
Drying the Coffee Beans Before Roasting
[0113] Another interesting aspect of this invention relates to
controlling the size and properties of the inventive ground roast
coffee tablets by low-moisture drying of the coffee beans that are
used to make the ground roast coffee from which these inventive
ground roast coffee tablets are subsequently made, i.e., by drying
these coffee beans to a moisture content below the 12% level of
conventional coffee beans prior to roasting. In particular, it is
possible to reduce the friability of these tablets by a factor of
as much as 2, 4, 6, 10 and even 100 by drying the coffee beans in
this manner. Also, corresponding reductions in tablet volume can be
achieved, which are on the order of 10%, 20% and even 30% as
compared to the volume of an otherwise identical tablet made from
conventionally dried coffee beans.
[0114] In accordance with this aspect of the invention, coffee
beans are further dried before roasting from a conventional
moisture content of .about.12% to a moisture content of
.ltoreq.10%, .ltoreq.8%, .ltoreq.7%, .ltoreq.6%, or even
.ltoreq.5%. Thus low-moisture drying the beans to a moisture
content of .about.0.5 to .about.10%, .about.2% to .about.7%,
.about.2% to .about.6%, .about.3% to .about.6%, or even .about.3%
to .about.5%, is contemplated. This additional drying may take
place at the end of the standard drying or may be added as an
additional drying step prior to roasting. However, in either case,
the moisture should be reduced prior to roasting.
[0115] This additional or low moisture drying can occur at any
suitable set of conditions in one or more additional drying steps
and is conveniently done by heating the coffee beans at from
70.degree. to 325.degree. F. (21.degree. to 163.degree. C.), or
.about.70.degree. F. to .about.300.degree. F., .about.120.degree.
F. to .about.275.degree. F., or even .about.160.degree. F. to
.about.250.degree. F. over drying times lasting .about.1 minute to
.about.24 hours, .about.30 minutes to .about.24 hours, .about.1
hour to .about.24 hours, .about.1 hour to .about.12 hours, .about.1
hour to .about.6 hours, or even .about.2 hours to .about.6 hours.
See, for example, U.S. Pat. No. 5,322,703 and U.S. Pat. No.
5,160,757, which describe methods for low-moisture drying coffee
beans prior to roasting. The disclosures of both of these patents
are incorporated herein by reference.
[0116] After moisture reduction in accordance with this aspect of
the invention, the low-moisture beans obtained can then be roasted
by any conventional technique, as discussed above. For example, the
low-moisture dried beans can be charged into a bubbling bed or
fluidized bed roaster where they contact a hot air stream at inlet
air temperature of from .about.350.degree. to .about.1200.degree.
F. (.about.177.degree. C. to .about.649.degree. C.) preferably from
.about.400.degree. F. to .about.800.degree. F. (.about.204.degree.
C. to .about.427.degree. C.), at roast times from .about.10 seconds
to not longer than .about.5.5 minutes, preferably from .about.10 to
.about.47 seconds.
[0117] The low-moisture dried coffees may be used alone or in
mixtures with other coffee beans, both low-moisture dried and
conventionally dried.
Flavorants
[0118] Flavorants, both liquid and solid, can be included in the
inventive coffee tablets in conventional amounts. Exemplary
flavorants include French vanilla, hazelnut, amaretto, cappuccino,
chocolate, mint, peppermint, cinnamon, vanilla, caramel, maple,
toffee, pumpkin, spices, Irish Cream, Kahlua.RTM., Creme Brulee,
and nut flavors such as almond and macadamia nut, and so forth.
[0119] A number of difficulties may arise when flavorants are added
to coffee products. First, flavorants are normally added at a
standardized level rather than at levels specifically targeted to a
type of consumer. Consequently, all consumers get the same relative
amount of flavor, whether or not they prefer a higher or lower
flavor intensity. Second, flavorants may segregate during shipping
and handling, so that the concentration of flavoring may vary
through the mass of the coffee product (for example, low at the top
of the canister and high at the bottom of the canister). Third, the
timing associated with when the aroma of the flavorant is released
during the brewing cycle is difficult to control, even though
generating different aromas at different times in the brew cycle
may be desirable.
[0120] In accordance with another aspect of this invention, these
problems are largely eliminated by including flavorants in the
inventive coffee tablets. For example, since all the ingredients of
the inventive coffee tablets have been compacted together,
segregation of flavorants is largely eliminated. Additionally, the
dry flavorant in U.S. Pat. No. 6,841,185 also helps prevent
segregation in the in-feed to the equipment, as described in that
patent. Moreover, because the inventive coffee tablets can be
formulated with different flavorants, and with different amounts of
flavorants, the desired flavor and intensity of a brewed coffee can
be easily customized to taste, by appropriately selecting and
combining different amounts of different flavored coffee tablets to
use in the brewing cycle. Moreover, since the coffee tablets can be
produced with the flavorants located in different portions
throughout the inventive coffee tablets (e.g., in the middle, on
the surface, in between the two), the timing associated with when
the aroma is released in the brew cycle can also be selected and
controlled.
[0121] As appreciated by coffee professionals, coffee flavorants
are normally added to coffee products by means of flavor carriers
that are provided to make dispensing, metering and mixing of the
flavorant with the coffee product easier. Moreover, these
carrier-containing flavorant compositions can be in dry, liquid, or
paste forms. In accordance with this invention, some flavor
carriers have surprisingly been found to act like binders in coffee
tablets. Encapsulated flavorants such as those described, for
example, in U.S. Pat. No. 6,841,185, can also be used. The entire
disclosure of this patent is incorporated herein by reference. In
this regard, it has been further found, in accordance with this
aspect of the invention, that by adding flavorants to the inventive
coffee tablets using the solid carriers described in U.S. Pat. No.
6,841,185, stronger tablets which generate a greater yield of
coffee solids in the brewed coffee product are obtained, as
compared with tablets which do not contain flavorant.
[0122] Use of a dry flavorant in formulating the inventive coffee
tablets has a number of benefits. Mixing a dry flavorant with a dry
coffee composition ensures that the flavor is uniformly distributed
within the coffee prior to tabletting. In addition, using a dry
flavor compositions allows tablets to be made in which some of the
flavor can be incorporated into a separate dry layer residing on
one or more surfaces, or in the middle of the tablet. It is also
possible to have some of the flavor mixed in with the ground roast
coffee and a second portion of the flavorant residing on the
surface of the tablet or arranged in a multi-layer arrangement with
other flavor layers. This not only provides an interesting visual
signal to the consumer that a flavorant or flavorants are present,
but it also allows for a time release characteristic associated
with the release of the aroma of the flavorant to be incorporated
into the tablet. For example, a first flavor layer may be placed on
the outside of the tablet to release a first aroma of the first
flavorant, and a second flavor layer may be placed in the inside of
the tablet to release a second aroma of the second flavorant later.
The first and second flavorants may have the same or different
flavors and aromas.
[0123] This same effect can also be achieved with flavor "bits"
which can be mixed in with the coffee and/or adhered to the
surface.
[0124] Normally, the dry flavorants used in making the inventive
coffee tablets will have a moisture content in the range of
.about.1% to .about.7%, a particle density in the range of
.about.0.1 g/cc to .about.0.8 g/cc, and a mean particle size
distribution in the range of .about.5 microns to .about.150
microns, although dry flavorants with moisture contents, particle
densities, and mean particle size distributions outside these
ranges can also be used. The ratio of coffee component particle
size to flavor component particle size is generally in the range of
from .about.100:1 to .about.5:1.
[0125] When dry flavorants are used in making the inventive coffee
tablets (including wet flavorants encapsulated in dry flavor
carriers), they are typically present in the amount of .about.0.5%
to .about.20% of flavorant, or .about.2% to .about.15%, more
preferably from .about.3% to .about.10%, .about.4% to .about.8%, on
a on a dry weight basis.
[0126] When liquid or paste flavorants are used in making the
inventive coffee tablets, they are typically present in the amount
of .about.0.5% to .about.20% of flavorant, or .about.1.5% to
.about.15% or .about.2% to .about.12%, more preferably from
.about.3% to .about.10%, or even .about.3% to .about.8%.
WORKING EXAMPLES
[0127] In order to more thoroughly describe this invention, the
following working examples are presented.
[0128] In all of the working examples below, percent brew solids
was calculated using a recognized correlation between the percent
brew solids of the brewed coffee product and the refractive index
of the brewed coffee product, with percent brew solids being
calculated as (549.209.times.RI)-731.575 (at a temperature basis of
29.degree. C.). The total brew solids was then determined by
multiplying the percent brew solids by the mass of brewed coffee
product, and the percent yield was calculated by dividing the total
extracted brew solids by the total mass of coffee placed in the
brewer (multiplied by 100).
[0129] In the working examples presented in co-pending U.S.
Provisional Patent Application Ser. No. 61/168,027, filed on Apr.
9, 2009 and entitled GROUND ROAST COFFEE TABLET (the entire
disclosure of which is incorporated herein by reference), the
calculated correlation between refractive index and percent brew
solids differed from the above correlation, as percent brew solids
was calculated as (560.224.times.RI)-746.216 (at a temperature
basis of 20.degree. C.). Additionally, the zero point measurement
for refractive index was measured at 1.33200, and has since been
adjusted to 1.33204. As a result, due to changes to the temperature
basis (from 20.degree. C. to 29.degree. C.) and the zero point
measurement for refractive index, the calculated percent brew
solids, total brew solids, and percent yield in the earlier working
examples were approximately 15% greater than the corresponding
calculated values determined and presented herein. For the working
examples that have been re-presented in the present application,
the percent brew solids, total brew solids, and percent yield have
been adjusted to correspond to the newly adopted correlations and
measurements (i.e., based on percent brew
solids=(549.209.times.RI)-731.575, and RI zero point=1.33204).
Example 1
Pre-Compression
[0130] Brazilian arabica coffee beans were roasted and ground. This
ground roast coffee had a Hunter L-color of 17.9, a bulk density of
0.294 g/cm.sup.3 and a mean particle size of 885 microns. The
ground roast coffee so made was formed into cylindrical tablets
containing .about.2.65 gms ground roast coffee (moisture content
4.75%) and having a diameter of about 24 to 24.5 mm by means of a
Fette Model 2200SE multiple station tabletting machine operating at
a rate of 90,000 tablets per hour (over 3000 tablets per hour per
station and a dwell time of .about.14 millisecond) under different
conditions in which the compaction force in the main or primary
compactions step was held constant but the compaction force in
pre-compression step was varied.
[0131] The hardness of the tablets so made was determined using a
Varian VK200 Tablet Hardness tester set in the N (Newton) mode,
while the friability of the tablets obtained using a Varian
Friabilator having a dual chamber drum by rotating 25 grams of the
tablets in the drum of the machine for 100 revolutions at a rate of
25 rpm and then determining the amount of these tablets that passes
through a #4 American Standard Wire Mesh screen. Multiple tablets
were tested for each batch of tablets made.
[0132] The tablets so formed were then brewed into brewed coffee
with Mr. Coffee.RTM. Model DR13 coffee makers, having a water
delivery rate of approximately 2.75 g/sec, using 10 tablets
(.about.26.5 gms) and 1420 ml of water for each batch of brewed
coffee brewed. For comparison purposed, a control experiment was
run in the same way but using 29.5 gms conventional coffee, i.e.,
ground roast coffee in untabletted form.
[0133] The Yield was calculated based on the grams of coffee solids
recovered in the in the brewed coffee (as determined by the mass
and % brew solids in this brewed coffee product). Meanwhile, the
Yield ratio was determined by comparing the Yield of coffee solids
obtained when using inventive coffee tablets in comparison with the
yield of coffee solids obtained in a control experiment in which
untabletted coffee was used. The absorbance was measured by placing
a sample of the brewed coffee in an 8 ml sealed vial, cooling the
sample for 15 minutes at room temperature; transferring the sample
to a cuvette and measuring the absorbance in a Genesys 10
Spectrophotometer at 480 nm wavelength. The absorbance per gram was
calculated by dividing the absorbance by the total mass of the
coffee tablets used in the brew.
[0134] The results obtained are set forth in the following Table
1:
TABLE-US-00001 TABLE 1 Example 1--Test Conditions and Results
Initial Final Tablet Comp, Comp, Mass, % Hardness, density, % Yield
kN kN g Friability N g/cm.sup.3 Yield Ratio Absorbance Abs/gram 4.9
39.6 2.62 18 33.1 0.90 29.8 1.22 1.808 0.069 20 39.7 2.68 2.5 50.8
0.96 30.1 1.23 1.763 0.066 29.7 39.7 2.66 6.1 45.0 0.96 27.6 1.13
1.750 0.065 37.6 39.7 2.63 4.5 46.5 0.95 29.6 1.21 1.821 0.069
[0135] As can be seen from this table, increasing the force used in
the pre-compression step increases the hardness and reduces the
friability of the tablets obtained without adversely the yield of
the coffee solids contained in the finish coffee obtained. Note,
also, that the tablets with better hardness/friability profiles had
densities of 0.95 g/cm.sup.3 or greater. In addition, the ratio
between the compression forces used in the pre-compression and main
compression steps ranged from .about.50% to .about.95%. Finally,
also note that the yield ratio was greater than 1 for each
experiment in this example, thereby indicating that the amount of
coffee solids extracted from a given amount of ground roast coffee
is significantly greater when that coffee is formulated into coffee
tablets in accordance with this invention rather than being used in
a conventional (untabletted) form.
Example 2
Pre-Compression
[0136] Example 1 was repeated using a coffee comprising a mixture
of arabica and robusta coffee beans. The ground roast coffee so
made had a bulk density of 0.28 g/cm.sup.3 prior to compaction with
a mean particle size of 720 microns. The tablets had a moisture
content of about 4.7%. Tablet mass was about 2.45 grams and 10
tablets were brewed.
[0137] The results obtained are set forth in the following Table
2:
TABLE-US-00002 TABLE 2 Example 2--Test Conditions and Results
Initial Final Tablet Comp, Comp, Mass, % Hardness, density, % Yield
kN kN g Friability N g/cm.sup.3 Yield Ratio Absorb Abs/g 5 50 2.44
20.7 30 0.89 29.4 1.16 1.935 0.080 19.9 49.9 2.40 2.0 47.1 0.97
29.6 1.17 1.904 0.079 20.5 51 2.46 2.4 46.7 0.97 29.3 1.16 1.938
0.079 30.3 50.6 2.46 6.1 46.4 0.98 28.5 1.13 1.951 0.079 40.2 50.2
2.45 6.6 40.8 0.98 28.2 1.11 1.939 0.080
[0138] As can be seen from Table 2, increasing the ratio of the
forces used in the pre-compression and main compression steps
dramatically reduced friability, while increasing hardness. As in
Example 1, the Yield Ratio for each experiment in this example also
significantly exceeded 1, thereby further demonstrating that more
coffee solids are extracted from the inventive tablets than are
extracted from an equivalent amount of ground roast coffee in
untabletted form. Note also that the best products (i.e., tablets
having the highest hardnesses and lowest friabilities) had
densities of 0.97 to 0.98 g/cm.sup.3 and that the ratio of
pre-compression to main compression forces ranged from .about.40%
to .about.80%.
Example 3
Pre-Compression
[0139] Examples 1 and 2 were repeated, except that a different
blend of arabica and robusta coffees was used, the ground roast
coffee produced having a density of 0.33 g/cm.sup.3 and a mean
particle size of 806 microns was used. The tablets were about 3
grams in mass with a moisture content of about 5.2%. For brewing,
29.9 to 30.5 grams of tablets were used while 33.32 grams of ground
roast coffee was used in the control experiment.
[0140] The results obtained are set forth in the following Table
3:
TABLE-US-00003 TABLE 3 Example 3--Test Conditions and Results
Initial Final Tablet Comp, Comp, Mass, % Hardness, density, % Yield
kN kN g Friability N g/cm.sup.3 Yield Ratio Absorb Abs/g 0.4 40
2.96 12.7 41.8 0.91 31.1 1.22 2.109 0.071 5.4 40.3 3.05 12.2 43.1
0.93 32.7 1.29 2.108 0.070 20.3 40.3 3.05 4.2 54.9 0.96 32.0 1.26
2.223 0.073 30.2 40.9 2.99 4.9 57 0.95 28.7 1.13 2.135 0.071 38.1
40.7 3.00 5.8 58.8 0.97 28.6 1.12 2.200 0.073
[0141] As can be seen from Table 3, a large drop in friability was
observed when the ratio of the force used in the pre-compression
step to the main compression step increased to .about.0.14:1 (14%)
or more. The densities of these low friability products exceeded
0.95 g/cm.sup.3, even though the yield ratio was maintained well
above 1.
Example 4
Pre-Compression
[0142] Example 3 was repeated using a higher force for the main
compression step.
[0143] The results obtained are set forth in the following Table
4:
TABLE-US-00004 TABLE 4 Example 4--Test Conditions and Results
Initial Final Tablet Comp, Comp, Mass, % Hardness, density, % Yield
kN kN g Friability N g/cm.sup.3 Yield Ratio Absorb Abs/g 5.4 50.6
2.98 17.4 45.1 0.96 30.1 1.18 2.273 0.076 19.9 50.8 2.99 4.2 56.1
0.98 30.2 1.18 2.214 0.074 29.8 50.5 3.02 3.6 59.6 0.99 28.6 1.12
2.174 0.072 40.8 50.1 2.99 8.3 63.0 1.01 32.1 1.26 2.184 0.073
[0144] Again, a dramatic drop in friability and an increase in
hardness was observed. In this case, all products had densities
greater than 0.96, without adversely affecting yield, while the
ratio of pre-compression to main compression forces ranged from
.about.37% to .about.82% in the tablets exhibiting good friability.
It should be noted that going to higher final compression alone did
not yield an improved friability, hardness, or yield.
Example 5
Addition of Instant Coffee
[0145] Coffee A was prepared from a mixture of ground roast arabica
and robusta coffees. Coffee B was prepared by forming a blend
comprising 95.2 wt. % of Coffee A and 4.8 wt. % of
commercially-available Folgers.RTM. brand instant coffee.
[0146] Coffees A and B were each made into tablets weighing about 3
grams each using a Fette Model 2090 rotary tablet press set up to
subject the tablets to a two-step compaction process in which the
pre-compression step was carried out at a lower compaction force
than the main compression step. Tablets were made using seven
different operating conditions. These conditions were some
combination of changes in operating speed (rpm), pre-compression
force, and/or main compression force. After compression, 10 tablets
were brewed in a Mr. Coffee.RTM. Accel (Model PRX 23) ADC
coffee-maker. After brewing, the percent of solids extracted into
the brew was measured by refractive index, which was then converted
into total solids extracted. The yield of the roast and ground
("R&G") coffee was calculated based on amount of solids
extracted divided by weight of coffee put into the brewer. The
yield of coffee solids extracted from the ground roast coffee
portions of the respective "Coffee B's" was determined by assuming
100% extraction of the instant coffee and subtracting the mass of
the instant coffee from the total solids extracted.
[0147] The following results were obtained:
TABLE-US-00005 TABLE 5 Example 5--Test Conditions and Results
Tablet % Solids R&G Tablet Tablet Volume at Mass, Brew in Brew,
extracted, R&G Vol. same Brew Solids Coffee Run g Solids g g
Yield cm.sup.3 cm.sup.3 A 1 3.17 0.65 8.58 8.58 0.27 3.17 3.17 B 1
3.08 0.82 10.72 9.24 0.32 3.11 2.47 A 2 3.05 0.62 8.13 8.13 0.27
3.09 3.09 B 2 2.98 0.80 10.59 9.16 0.32 2.98 2.32 A 3 3.06 0.64
8.46 8.46 0.28 3.18 3.18 B 3 3.07 0.82 10.84 9.37 0.32 3.16 2.48 A
4 2.98 0.60 7.89 7.89 0.26 3.06 3.06 B 4 3.0 0.71 9.40 7.96 0.28
3.05 2.58 A 5 3.0 0.60 7.96 7.96 0.27 3.03 3.03 B 5 3.01 0.71 9.40
7.96 0.28 2.95 2.57 A 6 2.9 0.55 7.33 7.33 0.25 3.01 3.01 B 6 3.0
0.93 12.23 10.79 0.38 3.1 1.85 A 7 2.94 0.76 10.09 10.09 0.34 2.93
2.93 B 7 3.04 0.79 10.40 8.94 0.31 3.01 2.92 Mean 3.01 0.63 8.35
8.35 0.28 3.06 3.06 of A Mean 3.03 0.80 10.51 9.06 0.32 3.05 2.42
of B Ratio 1.26 1.14 0.79
[0148] In the table above, the conversion from % Brew Solids to
Solids in Brew was based on an assumption that 1320 ml of liquid
brew was obtained for all products. This is a reasonable value for
what one would expect to come out of a brew basket based on using
1420 mls of water going into the brew. (This is different from what
was done in examples 1, 2, 3, 4, and 8 where the actual amount of
liquid brew was measured and used.)
[0149] As can be seen, the addition of the instant coffee not only
gave higher overall brew solids, but also increased the yield of
the coffee solids extracted from the ground roast (R&G) coffee
used. That is to say, more coffee solids was extracted from a given
amount of ground roast coffee when instant coffee was also included
in the inventive coffee tablets as compared to essentially
identical coffee tablets not containing instant coffee.
[0150] The last column on the right of Table 1 shows a calculated
tablet size that would be obtained if the tablets made from Coffee
B were resized to give the same overall extraction yield as the
tablets made from Coffee A. As can be seen, the resized tablets
made from Coffee B would be 20% smaller than the tablets made only
from Coffee A.
Example 6
Addition of Instant Coffee
[0151] Additional data was collected from the same runs disclosed
above in Example 5. This additional data is shown in Table 6 below
as well as attached FIG. 2 in which the labels for each data point
gives the fill volume for the die.
TABLE-US-00006 TABLE 6 Example 6--Test Conditions and Results
Coffee Run RPM Fill Volume Tablet Mass Fill Density A 1 17.47 9.12
3.17 0.348 B 1 17.24 8.23 3.08 0.374 A 2 17.47 9.12 3.05 0.334 B 2
17.24 8.23 3.0 0.365 A 3 34.48 9.12 3.06 0.336 B 3 34.48 8.45 3.07
0.363 A 4 34.48 9.12 2.98 0.327 B 4 34.48 8.45 2.99 0.354 A 5 34.48
9.12 3.00 0.329 B 5 34.48 8.45 3.01 0.356 A 6 51.72 9.565 2.90
0.303 B 6 50.63 9.12 3.00 0.329 A 7 51.72 9.565 2.94 0.307 B 7
50.63 9.12 3.04 0.333 Mean of A 9.247 3.014 0.326 Mean of B 8.579
3.027 0.353 Ratio 0.928 1.004 1.083
[0152] From Table 6 and FIG. 2, it can be seen that the fill volume
for Coffee B was less than the fill volume for Coffee A for each
run. Note, also, that the mass of Coffee A decreased, while that of
Coffee B remained fairly constant. In addition, although the fill
volume for Coffee A increased, it was always larger than the fill
volume for Coffee B. Comparing especially the highest machine
speed, the fill volume for Coffee B was 5% less than for Coffee A,
yet the tablet mass was 4% higher.
[0153] This shows that including instant coffee in the inventive
ground roast coffee tablets allows a more efficient fill of the
individual dies, and hence higher operating speeds of the machine,
before machine capacity is limited by die filling. This effect,
coupled with the lower mass made possible by including instant
coffee, as described in Example 5, enables even higher machine
operating speeds to be obtained.
[0154] The operating speed of tabletting machines should not be
increased so high that tablet mass decreases appreciably or varies
unacceptably for a given ground roast coffee. If tablets are
underweight relative to other tablets made from the same ground
roast coffee, a consumer may be dissatisfied because brewing the
tablets will result in too weak of a brew. Additionally, if the
tablet mass varies too much for a given ground roast coffee, a
consumer may be discouraged from using the tablets because the
resulting brew differs too much from use to use.
Example 7
Low-Moisture Drying of Coffee Beans
[0155] Coffee A was made by roasting Mexican arabica coffee beans
in a Neuhaus Neotec roaster for 3.3 minutes to an L-color of 12.2.
Coffee B was made from the same Mexican arabica coffee beans, which
were low-moisture dried to a moisture content of 5 wt. % before
roasting, and then roasted in a Neuhaus Neotec roaster for 2.3
minutes to an L-color of 12.6. Both coffees were ground roast to a
similar mean particle size (.about.760 microns), with Coffee A
exhibiting a moisture content of 4.9% and a density of 0.27
g/cm.sup.3 while Coffee B exhibited a moisture content of 5.0% and
a density of 0.22 g/cm.sup.3. Both coffees were then made into
tablets having a nominal diameter of 23.8 mm using a Fette Model
2200 rotary tablet press operating at a pre-compression force of 35
kN, a main compression force of 40 kN and an operating speed of
17.2 rpm. The mass of the ground roast coffee fed to the machine
was varied such that tablets made from Coffee A averaged 2.8 grams
while those from coffee B averaged 2.0 grams. Tablet A had an
average volume of 2.9 cm.sup.3 while tablet B had an average volume
of 2.0 cm.sup.3, a 30% reduction in volume. Friability was measured
and was found to be 0.95% for Coffee A and 0.06% for Coffee B,
which represents a reduction of over 90%, or by a factor of over
15.
[0156] After production, tablets were brewed in a Mr. Coffee.RTM.
Accel (Model PRX 23) automatic drip coffeemaker. Brewing was
conducted with 10 cups of water. Total coffee used was 30.9 g for
coffee A and 30.6 g for coffee B. After brewing the % brew solids
in the brewed coffee made from coffee A was found to be 0.66 wt. %,
while the % brew solids for the brewed coffee made from coffee B
was found to be 0.64 wt. %. In addition, the yield for coffee A was
found to be 28.4%, while the yield for coffee B was found to be
27.7%, even though coffee tablets B were .about.30% smaller.
[0157] As can be seen from this experiment, although much smaller
tablets were made in the case of Coffee B, the extraction of coffee
solids from Coffee B was essentially the same as that for Coffee A.
Moreover, the friability of the tablets made from Coffee B was
lower than the friability of the tablets made from Coffee A.
Example 8
Low-Moisture Drying of Coffee Beans
[0158] Example 7 was repeated using different machine operating
conditions for making the tablets. Table 7 compares the results
obtained using low-moisture dried coffee beans and non-low-moisture
dried (conventionally dried) coffee beans.
TABLE-US-00007 TABLE 7 Example 8--Test Conditions and Results
Compression, kN % Tablet Brew Brew Tablet Run Coffee RPM Pre- Main
Friability Mass Mass Solids Volume A Regular 17.2 16 21 1.26 2.84
31.3 0.75 3.2 Dried 17.2 15 20 0.31 1.99 29.8 0.61 2.2 B Regular
17.2 16 40 1.69 2.86 31.4 0.67 3.01 Dried 17.2 16 40 0.10 2.06 31.0
0.68 2.17 C Regular 17.2 26 42 0.96 2.85 31.3 0.75 3.55 Dried 17.2
25 40 0.10 2.02 30.2 0.7 2.06 D Regular 34.5 16 40 1.54 2.84 31.3
0.75 3.06 Dried 34.5 16 39 0.04 1.97 31.5 0.63 2.09 E Regular 34.5
25 30 1.56 2.64 29.6 0.6 2.84 Dried 34.5 25 31 0.29 1.96 31.4 0.73
2.05 F Regular 34.5 36 40 1.44 2.78 30.1 0.76 2.87 Dried 34.5 35 41
0.18 1.97 29.5 0.65 1.99
[0159] The mean values for the results obtained in Example 8, as
reported in Table 7, are reported in Table 8 below:
TABLE-US-00008 TABLE 8 Example 8--Mean Values for Test Results
Tablet Brewing Brew Tablet Set Coffee % Friability Mass Mass Solids
Volume Mean Regular 1.41 2.80 30.8 0.71 3.10 Mean Dried 0.17 2.00
30.6 0.67 2.10
[0160] The mean values for the combined results obtained in
Examples 7 and 8 are reported in Table 9 below:
TABLE-US-00009 TABLE 9 Examples 7 and 8--Mean Values for Test
Results from Both Examples Tablet Brewing Brew Tablet % Comparison
Coffee % Friability Mass Mass Solids Volume Yield Mean Regular 1.34
2.81 30.8 0.71 3.07 24.5 Mean Dried 0.15 2.00 30.6 0.66 2.09
32.4
[0161] From Tables 7, 8 and 9, it can be seen that reducing the
moisture content of the ground roast coffee before roasting enabled
a reduction in friability of about 90% and a reduction in tablet
volume of about 30%.
Example 9
Low-Moisture Drying of Coffee Beans
[0162] A regular roast, ground roast coffee was made using 55%
arabica coffee beans and 45% robusta coffee beans. On average, the
coffee beans were roasted to a Hunter L color of about 15.7 L over
a roast period of about 3.2 minutes. All coffees were treated by
typical processing to provide ground roast coffees have a typical
particle size of approximately 825 microns and a typical density of
about 0.33 g/cm.sup.3. A ground roast coffee was made from 10%
regular ground roast arabica coffee, 40% regular ground roast
robusta coffee, and 50% ground roast arabica coffee derived from
coffee beans that had been low-moisture dried to a moisture content
of about 5% to produce a ground roast coffee mixture comprising 60%
arabica and 40% robusta coffees, the coffee mixture having a mean
particle size of .about.635 microns and a density of .about.0.247
g/cm.sup.3. The roasted, ground roast coffees so made were formed
into tablets in a similar manner to that of the above Examples 7
and 8 using various different operating conditions. The tablets so
obtained were then used to brew brewed coffees in the same manner
as described above in connection with Examples 7 and 8. The various
conditions used and the results obtained are shown in the following
Table 10.
TABLE-US-00010 TABLE 10 Example 9--Test Conditions and Results
Compression, kN % Tablet Brew Brew Tablet Run Coffee Rate Pre Main
Friability Mass Mass Solids Volume A Regular 17.2 15 21 66.19 3.0
30.3 0.7 3.86 Dried 17.2 16 21 1.43 2.8 31.1 1.05 3.43 B Regular
17.2 16 40 1.62 3.2 31.7 0.77 3.17 Dried 17.2 16 41 0.45 3.0 29.8
0.77 2.98 C Regular 17.2 23 40 1.06 3.1 30.5 0.73 3.09 Dried 17.2
24 42 0.16 2.8 31.3 0.71 2.81 D Regular 17.2 24 60 1.57 3.15 31.46
0.78 3.07 Dried 17.2 25 60 0.22 2.95 29.5 0.77 2.85 E Regular 17.2
35 40 0.78 3.02 30.26 0.63 3.0 Dried 17.2 36 41 0.08 2.82 30.99
0.78 2.76 F Regular 34.5 15 41 3.03 3.06 30.61 0.75 3.18 Dried 34.5
16 40 0.31 2.86 31.46 0.80 2.93 G Regular 34.5 16 61 3.97 3.13
31.23 0.75 3.14 Dried 34.5 16 61 0.38 2.92 29.17 0.77 2.92 H
Regular 34.5 26 41 1.38 2.98 29.77 0.70 3.06 Dried 34.5 25 43 0.14
2.83 30.97 0.78 2.82 I Regular 51.7 16 40 4.13 2.91 29.11 0.75 3.10
Dried 51.1 15 41 0.76 2.58 30.98 0.80 2.73 H Regular 51.7 25 41
2.32 2.9 29.23 0.65 3.01 Dried 52.4 25 40 0.72 2.59 30.78 0.66 2.66
I Regular 51.7 24 60 2.28 2.94 32.02 0.9 2.93 Dried 52.2 24 61 0.52
2.61 30.9 0.8 2.60 J Regular 52.2 31 50 2.93 2.87 31.33 0.77 2.88
Dried 52.5 30 50 4.44 2.6 31.18 0.73 2.6
[0163] The mean values for the results obtained in Example 9, as
reported in Table 10, are reported in Table 11 below:
TABLE-US-00011 TABLE 11 Example 9--Mean Values for Test Results
Com- % Fri- par- abil- Tablet Brewing Brew Tablet ison Coffee Rate
ity Mass Mass Solids Volume Mean Regular 7.61 3.02 30.63 0.74 3.12
Mean Dried 0.80 2.78 30.68 0.79 2.84
[0164] Because the first friability data point reported in Table 10
(Run A, Regular Coffee, Friability) appears to be a bad data point,
the following Table 12 reports the mean values obtained in Table 10
with this bad data point being excluded.
TABLE-US-00012 TABLE 12 -Example 9-Mean Values for Test Results
with Bad Data Point Excluded Com- % Fri- par- abil- Tablet Brewing
Brew Tablet ison Coffee Rate ity Mass Mass Solids Volume Mean
Regular 2.28 3.02 30.66 0.74 3.06 Mean Dried 0.74 2.78 30.64 0.76
2.79
[0165] Tables 10, 11 and 12 show that forming the inventive ground
roast coffee tablets from 50% low-moisture dried coffee beans, at
least when roasted quickly to a dark color, reduced the friability
of these tablets by about 65% (or, by a factor of more than 3)
compared with otherwise identically prepared tablets made from
ground roasted coffees derived from conventionally dried
(.about.12% moisture content) coffee beans roasted to comparable
colors (i.e., within about two Hunter L units). In addition, a 9%
reduction in tablet volume was also achieved relative to tablets
made with the conventionally dried coffee beans.
[0166] Roast and ground coffee from pre-dried green coffee that has
not been quickly roasted to a dark enough color does not appear to
provide improved friability (i.e., does not provide decreased
friability) relative to non-pre-dried green coffee. For example,
pre-dried coffee roasted to 18.8 L and then ground and tabletted
did not show an improved friability vis-a-vis normal moisture beans
or vis-a-vis a 50/50 mix of pre-dry and normal moisture green
coffee.
Example 10
Liquid Flavor Carrier
[0167] Additional coffee tablets were made using the inventive
multi-step compaction process in general accordance with Examples
1-4 in which the magnitude of the initial compression step as well
as the speed of the press, as measured by dwell time in the main
compression step were varied. The results obtained are set forth in
the following Table 15 (runs b and d are from Example 3):
TABLE-US-00013 TABLE 15 Example 10-Set 1-Test Conditions and
Results Dwell Initial Final Hard- Fria- Ktab/ Time, Compression,
Compression, ness, bility, Run hr msec kN kN N % a 60 21.0 20.5
40.7 60.5 2.3 b 90 14.0 20.3 40.3 54.9 4.2 c 120 10.5 20 40.2 43.0
9.1 d 90 14.0 0.4 40 41.8 12.7
[0168] By comparing Runs b and d, which were carried out at the
same production rate (90,000 tablets/hr with a dwell time of 14.0
milliseconds), it can be seen that (as in the case of Examples 1-4)
the both hardness and friability are improved when the force
encountered in the initial compression step was more than about 20%
of the force encountered in the main or primary compression step in
accordance with this invention. It will also be noted, however,
that as the production rate of the inventive tablets increased
(runs a through c), hardness and friability declined somewhat
(although both were still better than the control, Run d).
[0169] Another set of experiments similar to Set 1 above was run
using a different coffee. The results obtained are set forth in the
following Table 16:
TABLE-US-00014 TABLE 16 Example 10-Set 2-Test Conditions and
Results Dwell Initial Final Hard- Fria- Ktab/ Time, Compression,
Compression, ness, bility, Run hr msec kN kN N % e 90 14.0 30.7
49.6 56.3 4.7 f 120 10.5 29.9 49.2 43.4 9.0 g 130 9.7 30.8 49.8
42.1 11.8
[0170] Again, these results show the same trend as in the above Set
1, i.e., that as the production rate of the inventive tablets
increased, hardness and friability declined somewhat.
[0171] Still another set of experiments similar to Sets 1 and 2
above was run using the same coffee and conditions of Set 2, except
that the inventive tablets contained 3 wt. % of a liquid flavor
carrier comprising propylene glycol and triacetin. The results
obtained are set forth in the following Table 17:
TABLE-US-00015 TABLE 17 Example 10-Set 3-Test Conditions and
Results Dwell Initial Final Hard- Fria- Ktab/ Time, Compression,
Compression, ness, bility, Run hr msec kN kN N % h 90 14.0 30.7
49.5 79.2 0.9 i 120 10.5 29.2 49.4 71.8 1.5 j 130 9.7 29.2 50.3
74.5 2.1
[0172] These results show the same trend as in the above Sets 1 and
2, i.e., that as the production rate of the inventive tablets
increased, hardness and friability declined somewhat. However,
Table 17 shows that the magnitude of this effect is greatly reduced
due to the presence of the liquid flavor carrier.
Example 11
Liquid Flavor Carrier
[0173] Brazilian coffee beans were roasted and ground. This ground
roast coffee had a Hunter L-color of 16.8 a bulk density of 0.31
g/cm.sup.3 and a mean particle size of 890 microns. The roasted and
ground coffee was separated into three batches. One batch was mixed
with 3 wt. % propylene glycol (PG), based on the total weight of
the composition obtained. A second batch was mixed 3 wt. % of a
90/10 w/w mixture of propylene glycol and triacetin (PG/TriA). No
flavor carrier was added to the third batch, although it was mixed
in a similar manner to the other batches. All mixing was done using
a Forberg mixer.
[0174] Each of the three batches were made into tablets using a
Fette 2200 SE tabletting press at a variety of conditions. Hardness
was measured immediately after production and again at least 6 days
after production. Friability was measured at least 6 days after
production.
[0175] All tablets were brewed in a Mr. Coffee.RTM. Accel (Model
PRX 23) ADC coffee-maker. Approximately 26 grams of tablets were
brewed for each product. The % brew solids and the yield of coffee
solids obtained in the final product were also determined.
[0176] Nine different runs were made at different operating
conditions, each run comparing the three different batches of
tablets as described above. Table 18 below shows the mean values
obtained for the hardness, friability, and brew yields obtained for
each of these experiments.
TABLE-US-00016 TABLE 18 Example 11- Set 1-Results Obtained Initial
Final Hardness % Hardness, Hardness, Change, % Brew % Coffee N N N
Fribilaity Solids Yield Absorbance Control 54.8 47.8 -7.0 7.8 0.72
35.1 1.88 Control + 77.6 79.8 2.2 1.1 0.8 39.2 2.1 propylene glycol
Control 56.4 49.7 -6.7 6.3 0.73 35.3 1.88 Control + 69.8 71.5 1.7
1.9 0.78 37.8 2.15 liquid mixture
[0177] As can be seen from Table 18, the addition of the liquid
carrier gave increased hardness and lower friability without
impairing brewing performance. Moreover, addition of the liquid
carrier also prevented the tablets from experiencing the same small
yet still significant decrease in hardness within their first week
of manufacture shown by the Control tablets.
[0178] Additionally, the liquid flavor carriers appear to be so
effective that use of such liquid flavor carriers can make very low
pre-compression forces viable at a high rate of manufacture (and
perhaps will make no pre-compression tablets viable at high rates
of manufacture). The following Table 19 shows examples of products
made with low initial compression. They are not as good as tablets
made with a higher initial compression; however, they may be
commercially acceptable.
TABLE-US-00017 TABLE 19 Example 11- Set 2-Results Obtained Initial
Final Dwell Compres- Compres- Hard- Fria- Ktab/ Time, sion, sion,
ness, bility, Coffee hr msec kN kN N % C-2 + PG 90 14.0 0.4 40.2
65.7 2.07 C-2 + PG/TriA 90 14.0 0.3 40.8 49.3 8.38 C-2 + PG/TriA 90
14.0 5 40.2 49.6 5.10 C-2 + PG/TriA 90 14.0 0.3 19.8 33.0 9.86 C-2
90 14.0 4.9 40.8 42.3 8.27
Example 12
Dry Flavorant
[0179] A brewed coffee was made with added dry French Vanilla
flavor added at 3% w/w level. The flavor compound was intended to
be used at a nominal 3% level (as discussed above in connection
with the discussion of flavor carriers and flavorants). The coffee
was turned into tablets in accordance with this invention using a
Fette Model 2090 rotary tablet press. Compression conditions used
were pre-compression of 22 kN and a main compression of 35 kN in a
rotary press having 29 stations with round dies of nominally 23.8
mm in diameter and operating at a speed of 25.9 rpm, thereby
producing 45,000 tablets per hour (about 1550 tablets per set of
compressions per die per hour; the other values herein for tablets
per hour using the Fette Model 2090 rotary tablet press can be
converted to tablets per set of compressions per die per hour by
dividing the hourly rate by 29 (there are 29 stations in the press
used). In the case of rpm, the tablets per set of compressions per
die per hour may be obtained by multiplying the rpm by 60 minutes
per hour). The tablets obtained had an average mass of 2.87 grams,
an average hardness of 112 N and an average friability of
0.26%.
[0180] After production, the tablets were filled into metalized tin
cans. Another set of cans was filled with a control sample composed
of the roast ground coffee from which the tablets were made in
untabletted form. Cans were sealed and stored at 70.degree. F.
After two weeks, these products were evaluated for the
concentration of certain volatiles in the outgas obtained from
these products at the time they were removed from their respective
cans.
[0181] In particular, for the control sample of conventional ground
roast coffee, a coffee sample was removed from the can and placed
in a closed container. In the case of the inventive coffee tablets,
the tablets were gently broken apart to a particle size roughly
equivalent to that of the conventional ground roast coffee of the
control sample, and placed in a closed container. The outgas from
the closed container of the conventional ground roast coffee and
the broken apart tablets were analyzed. The concentrations of 25
different compounds were measured by gas chromatography, some
representing the coffee volatiles recovered from the ground roast
coffee in both examples and others representing the French Vanilla
flavorant. The data obtained was normalized to enable a direct
comparison of the concentrations of these ingredients in their
respective outgases to one another.
[0182] The results obtained are provided in FIG. 3. As can be seen
from this figure, the coffee volatiles outgassed from both samples,
i.e., the conventional (untabletted) coffee and the inventive
coffee tablets, are essentially the same.
[0183] Approximately 15 months after the samples mentioned above
were analyzed, additional samples were taken from previously
unopened cans of both the inventive coffee tablets and the
conventional (untabletted) coffee. The above tests were repeated,
and the results obtained reported in FIG. 4. As can be seen from
this figure, essentially the same results were obtained.
[0184] Table 20, below, shows additional data collected with
respect to the Examples above:
TABLE-US-00018 TABLE 20 Example 12-- Results Obtained Bulk Density
L- Mean particle % H2O % H2O Aw Example coffee g/cm3 color Size,
microns Q250, % % Lipid water/lipid tablet roast ground Tablet 1
0.294 17.9 885 8.6 13.3 0.358 4.75 4.7 0.343 2 0.28 15.0 720 12.9
11.6 0.402 4.7 4.6 0.344 3 and 4 0.33 16.8 806 10.9 10.2 0.507 5.2
4.8 0.379 5 and 6 A 0.33 825 5.0 4.8 5 and 6 B instant added to
coffee A 7 and 8 A 0.27 12.2 754 4.9 7 and 8 B 0.22 12.6 765 5.0 9
Regular 0.33 825 5.0 4.8 9 Dried 0.247 635 4.5 10 Set 1 0.33 16.8
806 10.9 10.2 0.507 5.2 4.8 0.38 10 Set 2 0.31 16.8 890 7.4 13.0
0.408 5.3 5.1 0.39 10 Set 3 same coffee as set 2 but with liquid
flavor carrier 11 control 0.31 16.8 890 7.4 13.0 0.408 5.3 5.1 0.39
12 0.29 19.8 763 4.9
Example 13
Liquid Flavor Carrier
[0185] Two additional sets of coffee product were tabletted using
varying amounts of liquid flavor carrier and varying levels of
pre-compression and main compression. The first set of tabletted
product used roasted and ground Brazilian coffee beans, with a
Hunter L-color of .about.18.8, a bulk density of .about.0.293
g/cm.sup.3, a mean particle size of .about.874 microns, and a
moisture content of .about.3.2%. The first set of roasted and
ground coffee was separated into five batches. Four of the batches
were mixed with propylene glycol ("LFC") at levels of 0.5 wt. %,
1.0 wt. %, 3.5 wt. %, and 6.0 wt. %, respectively. The fifth batch
included no added liquid flavor carrier, but was mixed in a similar
manner to the other batches. All mixing was done using a Forberg
mixer.
[0186] Each of the five batches were made into tablets using a
Fette 2200 SE tabletting press at a variety of pre-compression and
main compression forces. All tablets were produced at a rate of
90,000 tablets per hour. Hardness was measured immediately after
production and again at least 6 days after production. Friability
was measured at least 6 days after production. The results of these
measurements are listed below in Table 21.
TABLE-US-00019 TABLE 21 Example 13--Set 1, Results Obtained Initial
Final Friability, % LFC, Pre/Main Hardness, N Hardness, N % 0%,
0/20 kN 18.7 18.4 50.1 0%, 0/40 kN 22.7 25.3 27.5 0%, 10/20 kN 18.0
17.5 62.4 0%, 20/30 kN 40.1 34.1 11.5 0%, 20/40 kN 38.3 36.1 8.2
0.5%, 0/20 kN 24.8 18.7 46.9 0.5%, 0/40 kN 35.7 29.6 16.9 0.5%,
10/20 kN 22.3 18.2 54.3 0.5%, 20/30 kN 49.3 36.3 2.7 0.5%, 20/40 kN
49.0 43.0 2.3 1.0%, 0/20 kN 27.7 20.7 42.7 1.0%, 0/40 kN 44.0 36.5
7.2 1.0%, 10/20 kN 26.7 19.5 7.2 1.0%, 20/30 kN 54.7 46.2 1.5 1.0%,
20/40 kN 55.0 50.0 1.5 3.5%, 0/20 kN 53.7 47.9 2.3 3.5%, 0/40 kN
60.5 71.7 0.5 3.5%, 10/20 kN 50.2 44.8 3.0 3.5%, 20/30 kN 81.5 88.2
0.23 3.5%, 20/40 kN 72.8 90.6 0.26 6.0%, 0/20 kN 46.7 64.5 0.1
6.0%, 0/40 kN 40.0 77.4 0.7 6.0%, 10/20 kN 48.0 66.8 0.15 6.0%,
20/30 kN 53.5 95.6 0.08 6.0%, 20/40 kN 48.3 93.9 0.00
[0187] The second set of tabletted product also used roasted and
ground Brazilian coffee beans, with a Hunter L-color of
.about.18.8, a bulk density of .about.0.293 g/cm.sup.3, a mean
particle size of .about.874 microns, and a moisture content of
.about.4.6%. The roasted and ground coffee was separated into three
batches. One batch was mixed with .about.3.5 wt. % propylene glycol
(PG), based on the total weight of the composition obtained. A
second batch was mixed with .about.1 wt. % propylene glycol. No
flavor carrier was added to the third batch, although it was mixed
in a similar manner to the other batches. All mixing was done using
a Forberg mixer.
[0188] Each of the three batches were made into tablets using a
Fette 2200 SE tabletting press at a variety of pre-compression and
main compression forces. All tablets were produced at a rate of
90,000 tablets per hour. Hardness was measured immediately after
production and again at least 6 days after production. Friability
was measured at least 6 days after production. The results of these
measurements are listed below in Table 22. The minimal improvements
in hardness and friability that accompanied the increases in liquid
flavor concentration, as compared to the significant improvements
observed in the test results of Example 10 and Example 13, set 1,
suggest these results may be bad data, although this has not been
confirmed.
TABLE-US-00020 TABLE 22 Example 13--Set 2, Results Obtained Initial
Final Friability, % LFC, Pre/Main Hardness, N Hardness, N % 0%,
0/20 kN 32.0 23.5 35.8 0%, 0/40 kN 43.8 40.0 11.5 0%, 10/20 kN 30.0
25.4 35.7 0%, 20/30 kN 58.0 47.5 2.2 0%, 20/40 kN 59.0 51.4 1.2
1.0%, 0/20 kN 35.5 25.3 26.8 1.0%, 0/40 kN 47.4 41.7 8.3 1.0%,
10/20 kN 31.3 23.1 32.6 1.0%, 20/30 kN 65.3 52.6 1.3 1.0%, 20/40 kN
61.7 53.8 1.1 3.5%, 0/20 kN 37.3 26.3 18.7 3.5%, 0/40 kN 50.8 44.3
4.9 3.5%, 10/20 kN 38.0 25.4 23.2 3.5%, 20/30 kN 66.8 54.5 1.4
3.5%, 20/40 kN 65.2 54.7 1.7
Example 14
Low Pre-Compression Tablets
[0189] Coffee beans including a mixture of washed arabicas,
naturals, and robustas were roasted and ground, producing a ground
coffee having a Hunter L-color of .about.13.4, a bulk density of
.about.0.275 g/cm.sup.3 and a mean particle size of .about.709
microns, and a moisture content of .about.4.5%. Tablets were formed
using varying pre-compression and final or main compression, and
the hardness and friability of each tablet was calculated in a
manner consistent with that described in Example 1. The results
obtained are set forth in the following Table 23:
TABLE-US-00021 TABLE 23 Example 14-- Results Obtained Dwell Initial
Final Tablet Hard- Fria- Ktab/ Time, Compres- Compres- Density,
ness, bili- hr msec sion, kN sion, kN g/cm.sup.3 N ty, % 82 15.3
0.5 9 0.640 7.4 81.7 82 15.3 0.5 20.7 0.817 26.5 13.7 82 15.3 0.4
25.2 0.859 29.5 10.4 82 15.3 0.6 41 0.894 22.8 16.9 82 15.3 10.3
24.8 0.871 35.8 8.5 82 15.3 5 39 0.878 21.9 23.3
[0190] As shown, in tablets formed using very low pre-compression
(less than 1 kN), initial increases in final or main compression
(from 9 kN to 25.2 kN) improve hardness and friability, while
further increases in main compression (from 25.2 kN to 41 kN)
actually diminish hardness and friability (i.e., decrease hardness
and increase friability), even though the density of the tablet has
increased. Further, a tablet with a lower main compression (24.8
kN) but higher pre-compression (10.3 kN) may provide improved
hardness and friability as compared to a tabled formed with a
higher main compression (39 kN) and a lower pre-compression (5
kN).
Example 15
Pre-Compression
[0191] Brazilian coffee beans were roasted and ground. This ground
roast coffee had a Hunter L-color of .about.18.8, a bulk density of
.about.0.301 g/cm.sup.3, a mean particle size of .about.878
microns, and a moisture content of .about.4.8%. The ground roast
coffee so made was formed into cylindrical tablets containing
.about.2.6-2.7 g ground roast coffee and having a diameter of about
24 to 24.5 mm by means of a Fette Model 2200SE multiple station
tabletting machine operating at rates of 70,000 and 90,000 tablets
per hour under different conditions in which the compaction forces
in the pre-compression and main or primary compaction steps were
varied.
[0192] The hardness and friability of the tablets were tested in a
manner consistent with the tablets of Example 1. The tablets so
formed were then brewed in a manner consistent with the tablets of
Example 1.
[0193] The Yield was calculated based on the grams of coffee solids
recovered in the brewed coffee (as determined by the mass and %
brew solids in this brewed coffee product). Meanwhile, the Yield
ratio was determined by comparing the Yield of coffee solids
obtained when using inventive coffee tablets in comparison with the
yield of coffee solids obtained in a control experiment in which
untabletted coffee was used.
[0194] The results obtained are set forth in the following Table
24:
TABLE-US-00022 TABLE 24 Example 15-- Results Obtained Dense Pre
Main Br Yield absorb tab ktab/hr Comp Comp Hard Fri Index Index
index absorb Abs/g 0.859 70 4 27 44.53 3.40 1.141 1.143 1.272 1.614
0.061 0.883 70 13.3 30.3 46.59 2.10 1.187 1.207 1.207 1.532 0.057
0.868 70 0.7 30.4 45.13 2.76 1.164 1.183 1.204 1.528 0.058 0.883 70
13.3 30.3 46.59 2.10 1.187 1.207 1.207 1.532 0.057 0.913 70 20 30.7
57.12 0.98 1.118 1.140 1.235 1.567 0.059 0.889 70 0.6 45.2 46.55
8.14 1.141 1.149 1.253 1.590 0.060 0.923 70 12.9 40.3 54.66 1.40
1.118 1.133 1.227 1.557 0.059 0.934 70 20 38.5 59.97 1.02 1.198
1.187 1.255 1.593 0.060 0.901 70 0.6 51.2 47.86 5.03 1.187 1.186
1.285 1.631 0.061 0.952 70 29.5 51.4 58.30 1.78 1.141 1.147 1.251
1.588 0.060 0.767 90 0.5 21.2 28.03 18.49 1.095 1.102 1.132 1.436
0.054 0.827 90 20.5 23.4 41.24 2.07 1.095 1.124 1.149 1.458 0.055
0.838 90 20 21 42.68 2.21 1.107 1.106 1.199 1.521 0.057 0.876 90
0.5 39.2 41.08 9.66 1.232 1.240 1.259 1.598 0.060 0.899 90 13 34.9
46.64 3.10 1.118 1.118 1.209 1.534 0.057 0.918 90 20.2 34.8 54.97
0.72 1.187 1.191 1.218 1.546 0.058 0.878 90 0.7 51.1 40.15 7.57
1.175 1.200 1.254 1.591 0.060 0.877 90 0.5 51.1 39.54 8.40 1.141
1.151 1.279 1.623 0.062 0.911 90 12.7 51.8 44.17 2.77 1.130 1.133
1.228 1.558 0.058 0.957 90 45.1 51.4 53.46 2.67 1.175 1.193 1.245
1.580 0.060
Example 16
Pre-Compression
[0195] Coffee beans including a mixture of washed arabicas,
naturals, dried coffees, and robustas were roasted and ground. This
ground roast coffee had a Hunter L-color of about 17-18, a bulk
density of .about.0.288 g/cm.sup.3 a mean particle size of about
700-800 microns, and a moisture content of .about.4.43%. The ground
roast coffee so made was formed into cylindrical tablets containing
.about.2.66 gms ground roast coffee and having a diameter of about
24 to 24.5 mm by means of a Fette Model 2200SE multiple station
tabletting machine operating at rates of 70,000 and 80,000 tablets
per hour under different conditions in which the compaction forces
in the pre-compression and main or primary compaction steps were
varied.
[0196] The hardness of the tablets so made was determined using a
Varian VK200 Tablet Hardness tester set in the N (Newton) mode,
while the friability of the tablets obtained using a Varian
Friabilator having a dual chamber drum by rotating 25 grams of the
tablets in the drum of the machine for 100 revolutions at a rate of
25 rpm and then determining the amount of these tablets that passes
through a #4 American Standard Wire Mesh screen. Multiple tablets
were tested for each batch of tablets made.
[0197] The tablets so formed were then brewed into brewed coffee
with Mr. Coffee.RTM. Model DR13 coffee makers, using 10 tablets
(.about.26.5 gms) and 1420 ml of water for each batch of brewed
coffee brewed. For comparison purposes, a control experiment was
run in the same way but using 26.5 gms conventional coffee, i.e.,
ground roast coffee in untabletted form.
[0198] The Yield was calculated based on the grams of coffee solids
recovered in the brewed coffee (as determined by the mass and
percent brew solids in this brewed coffee product). Meanwhile, the
Yield ratio was determined by comparing the Yield of coffee solids
obtained when using inventive coffee tablets in comparison with the
yield of coffee solids obtained in a control experiment in which
untabletted coffee was used.
[0199] The results obtained are set forth in the following Table
25:
TABLE-US-00023 TABLE 25 Example 16-- Results Obtained Dense Pre
Main Br Yield absorb tab ktab/hr Comp Comp Hard Fri Index Index
index absorb Abs/g 0.955 70 4.7 51.6 50.3 6.46 1.09 1.11 1.186 1.78
0.067 0.956 70 12.9 38.4 57.1 2.87 1.04 1.11 1.124 1.69 0.0662
0.955 70 13.4 45.9 60.4 0.98 1.13 1.14 1.226 1.84 0.0692 0.909 70
3.7 45.1 49.83 11.28 1.136 1.158 1.212 1.82 0.0692 0.916 70 5.3
45.3 49.40 12.28 1.146 1.157 1.218 1.83 0.0692 0.955 70 13.4 45.9
60.43 0.98 1.125 1.136 1.226 1.84 0.0692 0.955 70 4.7 51.6 50.29
6.46 1.094 1.113 1.186 1.78 0.067 1.012 70 29.3 51.8 71.49 1.46
1.094 1.101 1.176 1.76 0.0664 0.833 80 3.8 26.9 33.46 3.23 1.094
1.094 1.216 1.82 0.0684 0.856 80 13.5 27.3 38.27 2.71 1.115 1.108
1.214 1.82 0.0683
Example 17
High Hardness Tablets Without a Binder
[0200] Coffee 17A was prepared from coffee beans including a
mixture of arabicas, dried arabicas, and robustas, roasted and
ground to a Hunter L-color of .about.18, a bulk density of
.about.0.3125 g/cm.sup.3, a mean particle size of .about.760
microns, and a moisture content of .about.4.72%. Coffee 17B was
prepared from coffee beans including a mixture of arabicas, dried
arabicas, and robustas, roasted and ground to a Hunter L-color of
.about.18, a bulk density of .about.0.3125 g/cm.sup.3, a mean
particle size of .about.760 microns, and a moisture content of
.about.5.25%. Coffee 17C was prepared from decaffeinated coffee
beans, roasted and ground to a bulk density of .about.0.323
g/cm.sup.3, a mean particle size of .about.782 microns, and a
moisture content of .about.4.79%. Coffee 17D was prepared from
coffee beans including a mixture of washed arabicas, naturals, and
robustas having a Hunter L-color of .about.15.4, a bulk density of
.about.0.285 g/cm.sup.3, a mean particle size of .about.710
microns, and a moisture content of .about.4.89%. Coffee 17E was
prepared from 10% regular ground roast arabica coffee, 40% regular
ground roast robusta coffee, and 50% ground roast arabica coffee
derived from coffee beans that had been low-moisture dried to a
moisture content of about 5% to produce a ground roast coffee
mixture comprising 60% arabica and 40% robusta coffees, the coffee
mixture having a Hunter L color of .about.15.7, a mean particle
size of .about.635 microns, a density of .about.0.247 g/cm.sup.3
and a moisture content of .about.4.46%.
[0201] Coffees 17A, 17B, 17C, 17D, and 17E were each made into
tablets weighing about 2.66 grams each (ranging from about 2.62 g
to about 2.70 g) using a Fette Model 2090 rotary tablet press set
up to subject the tablets to a two-step compaction process in which
the pre-compression step was carried out at a lower compaction
force than the main compression step. Tablets were made using
several different operating conditions. These conditions were some
combination of changes in operating speed (rpm) and resulting
compression dwell time, pre-compression force, and/or main
compression force. Samples of the tablets from each run were tested
for hardness and friability, with average values calculated for
each of these properties. After compression, 10 tablets from each
run were brewed in a Mr. Coffee.RTM. Accel (Model PRX 23) ADC
coffee-maker. After brewing, the percent of solids extracted into
the brew was measured by refractive index, which was then converted
into total solids extracted.
[0202] As shown in Table 26 below, tablets having very high
hardnesses (i.e., >90N) were able to be produced without the aid
of binders.
TABLE-US-00024 TABLE 26 Example 17--Results Obtained Pre Main Rotor
dwell, Comp, Comp, pre/ avg avg % Brew tab Run Coffee tabs/hr rpm
ms kN kN main mass Hard Fri Solids density 301 17A 30,000 17.2 41.9
16.4 39.5 0.42 2.90 92.1 0.32 0.697 0.964 302 17A 30,000 17.2 41.9
24.8 40.6 0.61 2.80 95.5 0.81 0.754 0.979 225 17B 29,500 17.0 42.6
16.7 41 0.41 3.14 104.3 0.38 0.754 0.978 224 17B 30,000 17.2 41.9
25.5 38.5 0.66 3.03 117.4 0.41 0.709 1.003 93 17C 60,000 34.5 21.0
35.5 45.4 0.78 3.01 92.3 1.05 0.725 1.021 85 17C 30,400 17.5 41.4
15.9 35.3 0.45 3.18 94.2 1.77 0.748 0.982 .sup. 84A 17C 30,300 17.4
41.5 25.5 40.6 0.63 3.02 97.1 0.64 0.703 0.988 86 17C 30,000 17.2
41.9 15.9 45.5 0.35 3.19 104.4 0.74 0.776 1.006 91 17C 30,000 17.2
41.9 35 34.9 1.00 2.99 108.0 0.35 0.709 1.008 87 17C 29,500 17.0
42.6 24.7 45.5 0.54 3.13 108.8 0.54 0.77 1.023 92 17C 30,000 17.2
41.9 34.9 46 0.76 3.01 110.3 2.10 0.714 0.999 8 17D 30,600 17.6
41.1 21 42.7 0.49 2.90 104.4 0.30 0.737 1.001 2 17D 29,600 17.0
42.5 20.8 40.9 0.51 2.89 106.2 0.20 0.731 1.013 250 17E 60,000 34.5
21.0 15.9 60.8 0.26 2.92 90.6 0.38 0.77 0.999 247 17E 60,000 34.5
21.0 24.9 42.7 0.58 2.83 94.1 0.14 0.782 1.002 248 17E 60,000 34.5
21.0 29.2 40.6 0.72 2.78 96.8 0.26 0.686 1.007 241 17E 30,000 17.2
41.9 15.6 40.9 0.38 2.98 102.2 0.45 0.765 0.999 243 17E 30,300 17.4
41.5 25.2 59.5 0.42 2.95 103.2 0.22 0.77 1.035 244 17E 30,000 17.2
41.9 35.9 41.4 0.87 2.82 111.4 0.08 0.776 1.023 242 17E 30,000 17.2
41.9 24.2 41.5 0.58 2.84 114.0 0.16 0.714 1.009
Example 18
Hardness and Friability as a Function of Density,
Pre-Compression
[0203] Coffee 18A was prepared from coffee beans including a
mixture of washed arabicas, naturals, dried coffees, and robustas,
roasted and ground to a Hunter L-color of about 17-18, a bulk
density of .about.0.288 g/cm.sup.3, a mean particle size of about
700-800 microns, and a moisture content of .about.4.43%. Coffee 18B
was prepared from Brazilian coffee beans, roasted and ground to a
Hunter L-color of .about.18.8, a bulk density of .about.0.301
g/cm.sup.3, a mean particle size of .about.878 microns, and a
moisture content of .about.4.8%. Coffees 18A and 18B were then each
made into tablets weighing about 3 grams each using a Fette Model
2090 rotary tablet press set up to subject the tablets to a
two-step compaction process in which the pre-compression step was
carried out at a lower compaction force than the main compression
step. Tablets were made using several different operating
conditions. These conditions were some combination of changes in
operating speed (rpm) (and resulting compression dwell time),
pre-compression force, and/or main compression force. Samples of
the tablets from each run were initially tested for hardness and
density, with average values calculated for each of these
properties. At least 6 days after production, additional samples of
each run were tested for hardness, density, and friability, with
average values calculated for each of these properties. These
results were arranged by final density for each coffee, as shown in
Table 27 below.
[0204] As shown in Table 27, tablets having similar densities
exhibited widely varying friabilities and hardnesses.
TABLE-US-00025 TABLE 27 Example 18 -- Results Obtained Pre Main
Rate Comp Comp Dense coffee name (ktab/hr) (kN) (kN) tab Hard Fri
18A 80 3.8 26.9 0.833 33.46 3.23 18A 70 13.1 25 0.845 35.93 13.69
18A 70 4.9 27.9 0.847 38.76 2.79 18A 80 13.5 27.3 0.856 38.27 2.71
18A 80 8.9 29.8 0.861 40.36 2.08 18A 80 3.6 36.9 0.878 41.64 9.40
18A 70 5.6 30.6 0.880 44.39 2.00 18A 70 9 30.7 0.886 45.10 1.85 18A
80 3.8 43.2 0.895 42.43 9.79 18A 80 13.5 33.2 0.899 47.32 1.27 18A
70 4.9 34.6 0.900 49.16 2.59 18A 70 20.2 30.2 0.902 47.31 1.49 18A
70 12.9 29.9 0.902 47.15 2.29 18A 80 3.6 45.1 0.903 42.20 10.19 18A
80 20.6 32.4 0.905 50.96 1.06 18A 70 13.4 33.6 0.906 51.53 1.25 18A
70 3.7 45.1 0.909 49.83 11.28 18A 80 3.7 53.2 0.915 48.67 8.41 18A
70 5.3 45.3 0.916 49.40 12.28 18A 70 19.9 37.3 0.918 52.53 1.00 18A
70 4.8 47.5 0.922 53.13 6.70 18A 80 13.3 39.9 0.930 54.39 1.12 18A
70 13.4 40.4 0.935 57.47 1.13 18A 80 13.3 45.1 0.938 56.04 1.33 18A
80 19.9 39.9 0.940 58.68 0.64 18A 70 20.2 40.1 0.942 61.37 0.61 18A
70 13.4 45.9 0.955 60.43 0.98 18A 70 4.7 51.6 0.955 50.29 6.46 18A
70 12.9 38.4 0.956 57.06 2.87 18A 70 20 50.6 0.969 63.27 0.75 18A
80 38.8 51.4 0.983 64.58 1.72 18A 70 29.3 51.8 1.012 71.49 1.46 18B
90 0.5 21.2 0.767 28.03 18.49 18B 90 20.5 23.4 0.827 41.24 2.07 18B
90 20 21 0.838 42.68 2.21 18B 70 12.3 25 0.847 40.89 3.09 18B 90
0.5 30.6 0.858 40.46 7.33 18B 70 4 27 0.859 44.53 3.40 18B 70 20
25.3 0.861 46.34 1.95 18B 90 13.6 28 0.868 43.46 2.79 18B 70 0.7
30.4 0.868 45.13 2.76 18B 90 0.5 39.2 0.876 41.08 9.66 18B 90 0.5
51.1 0.877 39.54 8.40 18B 90 0.7 51.1 0.878 40.15 7.57 18B 70 13.3
30.3 0.883 46.59 2.10 18B 70 0.6 34.7 0.887 46.49 3.63 18B 70 0.6
45.2 0.889 46.55 8.14 18B 70 0.6 47.4 0.894 47.00 5.04 18B 70 13.1
31.2 0.897 49.61 1.51 18B 90 13 34.9 0.899 46.64 3.10 18B 70 0.6
51.2 0.901 47.86 5.03 18B 70 13.15 35.9 0.906 49.51 1.49 18B 90
12.7 51.8 0.911 44.17 2.77 18B 70 20 30.7 0.913 57.12 0.98 18B 90
20.2 34.8 0.918 54.97 0.72 18B 70 12.9 40.3 0.923 54.66 1.40 18B 90
20.4 44.2 0.932 54.27 1.46 18B 70 20 38.5 0.934 59.97 1.02 18B 70
29.5 51.4 0.952 58.30 1.78 18B 90 45.1 51.4 0.957 53.46 2.67 18B 70
12.9 37.4 50.45 1.55 18B 70 12.9 45.2 51.06 1.70 18B 70 17.1 37
53.93 0.79 18B 70 17 45.6 55.74 1.09 18B 90 13 29.9 43.42 2.68 18B
90 12.9 36.7 45.20 3.38 18B 90 13 44.9 48.28 2.76 18B 70 5.3 30.6
43.54 4.30 18B 70 5.3 36.8 45.96 4.71 18B 70 5.2 45.5 43.92
6.02
Example 19
Brew Dynamics
[0205] Coffee 19A was prepared from coffee beans including a
mixture of washed arabicas, naturals, dried coffees, and robustas,
roasted and ground to a Hunter L-color of about 17-18, a bulk
density of .about.0.288 g/cm.sup.3, a mean particle size of about
700-800 microns, and a moisture content of .about.4.43%, and was
made into tablets in five separate runs (A, B, C/D, E, and F), the
tablets weighing about 2.65 grams each, using a Fette Model 2090
rotary tablet press set up to subject the tablets to a two-step
compaction process in which the pre-compression step was carried
out at a lower compaction force than the main compression step.
Tablets were made using the operating conditions identified in
Table 28 below. Coffee 19B was prepared from Brazilian coffee
beans, roasted and ground to a Hunter L-color of .about.18.8, a
bulk density of .about.0.301 g/cm.sup.3, a mean particle size of
.about.878 microns, and a moisture content of .about.4.8%, and was
made into tablets in a single run (G), the tablets weighing about
2.65 grams each, using a Fette Model 2090 rotary tablet press set
up to subject the tablets to a two-step compaction process in which
the pre-compression step was carried out at a lower compaction
force than the main compression step. Tablets were made using the
operating conditions identified in Table 28 below. Samples of the
tablets from each run were tested for hardness and friability, with
average values for each of these properties shown in Table 28.
Additionally, tablets of a competitive tabletted coffee product (H)
were collected for testing, as identified in Table 28 below.
[0206] After compression, 10 tablets from each run (totaling
approximately 26.5 g), equivalent amounts of the corresponding
roasted and ground coffee, and 4 tablets (totaling approximately
28.7 g) of the competitive tabletted coffee product, were brewed
with approximately 1420 g water in a Mr. Coffee.RTM. Accel (Model
PRX 23) ADC coffee-maker having a water delivery rate of
approximately 2.75 g/sec. To measure instantaneous brew
characteristics at increments throughout the brew (or "brew
dynamics"), the brew was collected at 20 second increments in
separate, small containers. For each 20 second accumulation or
sample of brew, mass, refractive index, and absorbance were
measured, and amount of brew solids and yield were determined from
the measured refractive index (as explained in greater detail
above). The samples were then incrementally and chronologically
combined to measure and calculate cumulative mass, refractive
index, brew solids, and yield.
TABLE-US-00026 TABLE 28 Example 19, Set 1-- Results Obtained Pre-
Main Hard- Fria- Code Ktab/ compression, Compression, ness, bility,
Density, letter hr kN kN N % g/cm.sup.3 A 80 3.6 45.1 42.2 10.2
0.903 B 70 4.8 47.5 53.1 6.7 0.922 C 70 17.2 45.2 63 0.9 D 70 17.2
45.2 63 0.9 E 70 29.3 51.8 71.5 1.5 1.012 F 80 38.8 51.4 64.6 1.7
0.983 G 70 17 45.6 55.7 1.1 H
[0207] FIG. 5 graphically illustrates the average instantaneous
coffee solids concentration over the course of the brew for the low
pre-compression tablets (A and B) of Coffee 19A, the high
pre-compression tablets (C, D, E, and F) of Coffee 19A, Coffee 19A
in roast and ground form, and the competitor tablet H. As shown,
the roast and ground coffees and the competitive coffee tablets
exhibit higher instantaneous concentrations in an initial portion
of the brews (i.e., the first 200-300 g of brew), while the
inventive tabletted coffees exhibit higher instantaneous
concentrations than their roast and ground counterparts and the
competitive tabletted coffee subsequent to these initial portions,
most substantially so in a mid-range portion of the brews (i.e.,
the 200-300 g of brew immediately following the initial 200-300 g
of brew).
[0208] FIG. 6 graphically illustrates the average cumulative
extracted coffee solids over the course of the brew for the low
pre-compression tablets (A and B) of Coffee 19A, the high
pre-compression tablets (C, D, E, and F) of Coffee 19A, Coffee 19A
in roast and ground form, and the competitor tablet H. As shown,
the tabletted coffees exhibited an initial lag in extraction, as
compared to their roast and ground coffee counterparts, while
exceeding the extraction of the roast and ground coffees after an
intermediate point in the brew (i.e., about 550-850 g into the
brew).
[0209] FIGS. 7 and 8 graphically illustrate the instantaneous
coffee solids concentration and cumulative extracted coffee solids
over the course of the brew for Coffee 19B in tabletted and roast
and ground form, again showing higher initial instantaneous
concentrations of coffee solids for the roast and ground coffee,
and higher mid-range instantaneous concentrations of coffee solids
for the tabletted coffee, as well as an initial lag in extraction
for the tabletted coffee, as compared to the roast and ground
coffee counterpart, with the tabletted coffee exceeding the
extraction of the roast and ground coffees after an intermediate
point in the brew (i.e., about 550-850 g into the brew).
[0210] FIGS. 9 and 10 graphically show similar results in
separately comparing five different runs of tablets produced from
Coffee 19A as compared to their corresponding roast and ground
coffee counterpart.
[0211] As an alternative measure of the initial and mid-range brew
characteristics, 10 tablets from each run (totaling approximately
26.5 g), equivalent amounts of the corresponding roasted and ground
coffee, and 4 tablets (totaling approximately 28.1 g) of the
competitive tabletted coffee product, were again brewed with
approximately 1420 g water in a Mr. Coffee.RTM. Accel (Model PRX
23) ADC coffee-maker. An initial approximately 250 g portion of
each brew was collected and a subsequent 250 g ("mid-range")
portion immediately following the initial portion was collected.
For each of the initial and mid-range portions, refractive index
and absorbance were measured, and amount of brew solids and yield
were determined from the measured refractive index (as explained in
greater detail above). The samples were then combined with the
remainder of each total brew to measure and calculate mass,
refractive index, brew solids, and yield for each total brew. As
evident in Table 29 below, coffee brewed from the inventive coffee
tablets produced with higher pre-compression force (i.e., greater
than 30% of the main compression force) exhibited the lowest
initial brew solids and absorbances and the highest mid-range brew
solids and absorbances. Coffee brewed from the roasted and ground
coffee samples exhibited the highest initial brew solids and
absorbances and the lowest mid-range brew solids and absorbances.
Coffee brewed from the inventive coffee tablets produced with lower
pre-compression forces (8-10% of the main compression force)
exhibited higher initial brew solids and absorbances and lower
mid-range brew solids and absorbances that the coffee brewed from
the higher pre-compression tablets. Coffee brewed from the
competitive coffee tablets exhibited higher initial brew solids and
absorbances and lower mid-range brew solids and absorbances that
the coffee brewed from the lower pre-compression tablets.
TABLE-US-00027 TABLE 29 Example 19, Set 2-- Results Obtained
Product: R&G R&G tab tab tab tab tab tab tab prior code:
for A-F for G H "A" "B" "F" "C" "G" "E" Process Conditions rate
ktab/hr na na 80 70 80 70 70 70 pre-compression na na 3.6 4.8 38.8
17.2 17 29.3 main-compression na na 45.1 47.5 51.4 45.2 45.6 51.8
Tablet Properties Hardness na na 42.2 53.1 64.6 63.0 55.7 71.5
Friability na na 10.2 6.7 1.7 0.9 1.1 1.5 Brewing Brewer Mr. C Mr.
C Mr. C Mr. C Mr. C Mr. C Mr. C Mr. C Mr. C grams brew S1 252.0 253
251 251.4 252.4 252 251.5 252 249.4 (liquid): grams brew S2 250.2
249 251 251.4 249.7 251 250.4 250 252.6 (liquid): total: 502.2
502.4 501.8 502.7 502.0 503.1 501.9 502.4 502.0 ratio S1/S2 1.01
1.02 1.00 1.00 1.01 1.00 1.00 1.01 0.99 absorbance S1 3.421 2.555
2.67 2.276 2.44 1.798 1.786 1.657 1.136 absorbance S2 1.549 1.317
2.181 3.11 3.109 3.288 3.309 3.111 3.258 grams solids S1 4.661 3.39
2.99 2.49 2.62 1.89 1.91 2.02 1.20 grams solids S2 1.126 1.27 1.98
3.24 3.05 3.72 3.98 3.43 3.79 Analysis S2/S1 ratio absorbance 0.45
0.52 0.82 1.37 1.27 1.83 1.85 1.88 2.87 solids extracted 0.24 0.37
0.66 1.30 1.16 1.97 2.08 1.70 3.17 S1/S2 ratio absorbance 2.21 1.94
1.22 0.73 0.78 0.55 0.54 0.53 0.35 solids extracted 4.14 2.67 1.51
0.77 0.86 0.51 0.48 0.59 0.32 S1/total (solids) 0.707 0.577 0.452
0.343 0.354 0.261 0.256 0.302 0.165 S2/total (solids) 0.171 0.216
0.3 0.446 0.411 0.513 0.534 0.513 0.522
Example 20
Tablet Properties at High Production Rates
[0212] Coffee 20A was prepared from coffee beans including a
mixture of washed arabicas, naturals, and robustas, roasted and
ground to a Hunter L-color of .about.15.6, a bulk density of
.about.0.285 g/cm.sup.3, a mean particle size of .about.690
microns, and a moisture content of .about.4.8%. Coffee 20B was
prepared from coffee beans including a blend of arabicas and
robustas, roasted and ground to a Hunter L-color of .about.16.8, a
bulk density of .about.0.33 g/cm.sup.3, a mean particle size of
.about.806 microns, and a moisture content of .about.5.2%. Coffee
20C was prepared from coffee beans including a mixture of arabicas,
dried coffees, and robustas, roasted and ground to a Hunter L-color
of .about.16, a bulk density of .about.0.288 g/cm.sup.3, a mean
particle size of .about.760 microns, and a moisture content of
4.3%. Coffee 20D was prepared from Brazilian coffee beans, roasted
and ground to a Hunter L-color of .about.17.9, a bulk density of
.about.0.294 g/cm.sup.3, a mean particle size of .about.885
microns, and a moisture content of .about.4.7%. Coffee 20E was
prepared from Brazilian coffee beans, roasted and ground to a
Hunter L-color of .about.16.8, a bulk density of .about.0.311
g/cm.sup.3, a mean particle size of .about.890 microns, and a
moisture content of .about.5.1%. Coffee 20F was prepared from
coffee beans including a mixture of arabicas, dried coffees, and
robustas, roasted and ground to a Hunter L-color of .about.15, a
bulk density of .about.0.28 g/cm.sup.3, a mean particle size of
.about.720 microns, and a moisture content of .about.4.6%. Coffee
20G was prepared from Brazilian coffee beans, roasted and ground to
a Hunter L-color of .about.18.8, a bulk density of .about.0.301
g/cm.sup.3, a mean particle size of .about.878 microns, and a
moisture content of .about.4.8% Coffee 20H was prepared from
Brazilian coffee beans, roasted and ground to a Hunter L-color of
.about.18.8, a bulk density of .about.0.305 g/cm.sup.3, a mean
particle size of .about.878 microns, and a moisture content of
.about.5%. Coffee 201 was prepared from Brazilian coffee beans,
roasted and ground to a Hunter L-color of .about.18.8, a bulk
density of .about.0.301 g/cm.sup.3, a mean particle size of
.about.878 microns, and a moisture content of .about.4.8%. Coffee
20J was prepared from coffee beans including a mixture of dried and
regular Brazilian coffees, roasted and ground to a Hunter L-color
of .about.18.8, a bulk density of .about.0.329 g/cm.sup.3, a mean
particle size of .about.878 microns, and a moisture content of
.about.4.6%. Coffee 20K was prepared from Brazilian coffee beans,
roasted and ground to a Hunter L-color of .about.18.8, a bulk
density of .about.0.316 g/cm.sup.3, a mean particle size of
.about.868 microns, and a moisture content of .about.4.6%. Each
coffee was made into tablets in several runs, using a Fette Model
2090 rotary tablet press set up to subject the tablets to a
two-step compaction process. The production runs used varying
tablet masses, production rates/dwell times, and pre-compression
and main compression forces. For a number of production runs,
relatively high production rates (or low compression dwell times)
were used. For production rates of 90,000 to 120,000 tabs per hour
(9.7 ms-14 ms compression dwell time), tablets having relatively
high hardness (greater than 40 N) and relatively low friability
(less than 10) were produced, as shown in Table 30 below.
[0213] After compression, 10 tablets from each run (totaling
approximately 26-27 g) were brewed with approximately 1420 g water
in a Mr. Coffee.RTM. Accel (Model PRX 23) ADC coffee-maker. After
brewing, the absorbance of the brew was measured, as described
above, and the percent of solids extracted into the brew was
measured by refractive index, which was then converted into total
solids extracted and yield.
TABLE-US-00028 coffee ktab/ dwell Pre Main pre/ Tablet Refr Brew
Yield abs/ Br Yield abs name Run mass hr time Comp Comp main Hard
Fri density Index Solid % Abs. gram index Index index 20A 19 2.70
120 10.5 20.6 41 0.50 52.5 2.6 1.029 1.33326 0.603 28.5 2.071 0.077
1.10 1.06 20A 18 2.64 120 10.5 20.5 31 0.66 46.9 6.1 0.976 1.33322
0.583 28.4 2.122 0.081 1.10 1.09 20A 20 2.68 120 10.5 30.8 40.2
0.77 52.6 7.6 1.034 1.33329 0.616 29.5 2.142 0.079 1.14 1.10 20B 4
2.97 90 14.0 40.8 50.1 0.81 63.0 8.3 1.011 1.33355 0.740 32.1 2.184
0.073 1.26 1.12 20B 16 3.03 120 10.5 30.2 40 0.76 50.8 8.6 0.952
1.33343 0.683 29.6 2.242 0.075 1.16 1.15 20B 17 3.00 120 10.5 30.1
45.5 0.66 54.1 7.1 0.968 1.33344 0.689 29.4 2.252 0.074 1.15 1.16
20B 2 2.96 90 14.0 19.9 50.8 0.39 56.1 4.2 0.979 1.33347 0.702 30.1
2.214 0.074 1.18 1.14 20C 5 2.66 90 14.0 40.0 55.8 0.72 56.1 5.7
0.990 1.33325 0.598 28.6 2.059 0.077 1.12 1.10 20C 2 2.64 90 14.0
20.1 50.9 0.39 55.5 2.6 0.977 1.33328 0.612 29.3 1.991 0.074 1.15
1.06 20D 16 2.62 130 9.7 26.5 46 0.58 41.5 8.1 0.953 1.33327 0.607
29.7 1.906 0.072 1.22 1.17 20E 4 2.67 90 14 30.7 49.6 0.62 56.3 4.7
0.993 1.33329 0.616 29.9 1.838 0.069 1.23 1.09 20E 1 2.65 90 14
29.9 40.4 0.74 52.7 4.2 0.983 1.33323 0.588 28.4 1.948 0.073 1.17
1.16 20F 1 2.45 90 14 40.2 50.2 0.8 40.8 6.6 0.984 1.3331 0.526
28.2 1.939 0.080 1.11 1.17 20F 8 2.40 90 14 19.9 49.9 0.4 47.1 2.0
0.973 1.33316 0.555 29.5 1.904 0.079 1.17 1.15 20G 17 2.65 90 13.9
20.2 34.8 0.6 55.0 0.7 0.918 1.33309 0.570 27.6 1.546 0.058 1.19
1.191 1.218 20G 19 2.68 90 13.9 45.1 51.4 0.9 53.5 2.7 0.957
1.33308 0.565 27.6 1.580 0.060 1.18 1.193 1.245 20H 4 2.65 90 13.9
24.9 35.4 0.7 51.6 3.1 0.922 1.33300 0.521 25.7 1.553 0.060 1.08
1.099 1.241 20H 7 2.59 100 12.7 29.6 40.8 0.7 43.7 4.7 0.923
1.33304 0.543 26.5 1.530 0.057 1.13 1.132 1.223 20G 18 2.67 90 13.9
20.4 44.2 0.5 54.3 1.5 0.932 1.33306 0.554 26.5 1.545 0.058 1.15
1.146 1.217 20I 1 2.65 90 14.2 20.3 40.2 0.5 51.4 1.2 1.33307 0.559
27.6 1.571 0.060 1.13 1.143 1.205 20J 6 2.67 90 13.9 25.4 35 0.7
45.1 3.6 1.33306 0.554 26.7 1.469 0.055 1.20 1.178 1.313 20K 7 2.65
90 13.9 24.5 35.2 0.7 53.8 1.9 1.33305 0.548 26.8 1.634 0.062 1.11
1.121 1.347
[0214] Although only a few embodiments of this invention have been
described above, it should be appreciated that many modifications
can be made without departing from the spirit and scope of the
invention. All such modifications are intended to be included
within the scope of this invention, which is to be limited only by
the following claims.
[0215] While various inventive aspects, concepts and features of
the inventions may be described and illustrated herein as embodied
in combination in the exemplary embodiments, these various aspects,
concepts and features may be used in many alternative embodiments,
either individually or in various combinations and sub-combinations
thereof. Unless expressly excluded herein all such combinations and
sub-combinations are intended to be within the scope of the present
inventions. Still further, while various alternative embodiments as
to the various aspects, concepts and features of the
inventions--such as alternative materials, structures,
configurations, methods, devices and components, alternatives as to
form, fit and function, and so on--may be described herein, such
descriptions are not intended to be a complete or exhaustive list
of available alternative embodiments, whether presently known or
later developed. Those skilled in the art may readily adopt one or
more of the inventive aspects, concepts or features into additional
embodiments and uses within the scope of the present inventions
even if such embodiments are not expressly disclosed herein.
Additionally, even though some features, concepts or aspects of the
inventions may be described herein as being a preferred
arrangement, composition, or method, such description is not
intended to suggest that such feature is required or necessary
unless expressly so stated. Still further, exemplary or
representative values and ranges may be included to assist in
understanding the present disclosure; however, such values and
ranges are not to be construed in a limiting sense and are intended
to be critical values or ranges only if so expressly stated.
Moreover, while various aspects, features and concepts may be
expressly identified herein as being inventive or forming part of
an invention, such identification is not intended to be exclusive,
but rather there may be inventive aspects, concepts and features
that are fully described herein without being expressly identified
as such or as part of a specific invention. Descriptions of
exemplary methods or processes are not limited to inclusion of all
steps as being required in all cases, nor is the order that the
steps are presented to be construed as required or necessary unless
expressly so stated. Also, the various features discussed above and
claimed below may be considered to be separate building blocks
which may provide utility in and of themselves. Thus, it is
contemplated that inventive devices and arrangements may be
designed based on the teachings herein using virtually any
combination or permutation of any one or more of these separate
features without necessarily some or all of the other features.
Accordingly, it is contemplated that tabletted products and their
methods of production and use may be claimed using virtually any
combination or permutation of any one or more of these
features.
* * * * *