U.S. patent application number 10/272968 was filed with the patent office on 2003-05-29 for liquid coffee concentrates.
This patent application is currently assigned to The Procter & Gamble Co.. Invention is credited to Dria, Glenn James, Li, Jianjun Justin, Nunes, Raul Victorino, Patton, Donald Ray, Young, Jerry Douglas.
Application Number | 20030099752 10/272968 |
Document ID | / |
Family ID | 23354150 |
Filed Date | 2003-05-29 |
United States Patent
Application |
20030099752 |
Kind Code |
A1 |
Dria, Glenn James ; et
al. |
May 29, 2003 |
Liquid coffee concentrates
Abstract
Improved liquid coffee concentrates that have furfuryl acetate
to 4-ethyl guaiacol ratio values that approach the furfuryl acetate
to 4-ethyl guaiacol ratio values of fresh brewed coffees brewed
with the same coffees used to produce said coffee concentrates are
disclosed. Methods of evaluating and adjusting a liquid coffee
concentrate's furfuryl acetate to 4-ethyl guaiacol ratio value are
also disclosed.
Inventors: |
Dria, Glenn James; (Okeana,
OH) ; Young, Jerry Douglas; (Cincinnati, OH) ;
Nunes, Raul Victorino; (Loveland, OH) ; Li, Jianjun
Justin; (West Chester, OH) ; Patton, Donald Ray;
(Cincinnati, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY
INTELLECTUAL PROPERTY DIVISION
WINTON HILL TECHNICAL CENTER - BOX 161
6110 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Assignee: |
The Procter & Gamble
Co.
|
Family ID: |
23354150 |
Appl. No.: |
10/272968 |
Filed: |
October 17, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60345234 |
Oct 19, 2001 |
|
|
|
Current U.S.
Class: |
426/594 |
Current CPC
Class: |
A23F 5/243 20130101 |
Class at
Publication: |
426/594 |
International
Class: |
A23F 005/00 |
Claims
What is claimed:
1. A coffee concentrate, said coffee concentrate being a liquid and
having a furfuryl acetate to 4-ethyl guaiacol ratio value that is
from about 50% to about 210% of the furfuryl acetate to 4-ethyl
guaiacol ratio value of fresh brewed coffee brewed with the same
coffee used to produce said coffee concentrate.
2. The coffee concentrate of claim 1 wherein said furfuryl acetate
to 4-ethyl guaiacol ratio value is from about 65% to about 150% of
the furfuryl acetate to 4-ethyl guaiacol ratio value of fresh
brewed coffee brewed with the same coffee used to produce said
coffee concentrate.
3. The coffee concentrate of claim 2 wherein said furfuryl acetate
to 4-ethyl guaiacol ratio value is from about 80% to about 120% of
furfuryl acetate to 4-ethyl guaiacol ratio value of fresh brewed
coffee brewed with the same coffee used to produce said coffee
concentrate.
4. A product comprising the coffee concentrate of claim 1.
5. A product according to claim 4 wherein said coffee concentrate's
furfuryl acetate to 4-ethyl guaiacol ratio value is from about 65%
to about 150% of furfuryl acetate to 4-ethyl guaiacol ratio value
of fresh brewed coffee brewed with the same coffee used to produce
said coffee concentrate.
6. A product according to claim 4 wherein said coffee concentrate's
furfuryl acetate to 4-ethyl guaiacol ratio value is from about 80%
to about 120% of furfuryl acetate to 4-ethyl guaiacol ratio value
of fresh brewed coffee brewed with the same coffee used to produce
said coffee concentrate.
7. A process for producing an improved coffee concentrate, said
process comprising the steps of: a.) providing a liquid coffee
extract; and b.) subjecting said liquid extract to heat treating
for an equivalent time of from about 15 seconds to about 35 seconds
at an equivalent temperature of from about 115.degree. C. to about
149.degree. C.
8. The process of claim 7 wherein said liquid extract is subjected
to heat treating for an equivalent time of from about 16.5 seconds
to about 30 seconds at an equivalent temperature of from about
126.degree. C. to about 149.degree. C.
9. The process of claim 8 wherein said liquid extract is subjected
to heat treating for an equivalent time of from about 18 seconds to
about 28 seconds at an equivalent temperature of from about
137.degree. C. to about 149.degree. C.
10. The process of claim 7 wherein said liquid extract is a
non-hydrolysed liquid having a pyridine to 5-methyl-2-furfurylfuran
ratio value of from about 3:1 to about 25:1 and a solids content,
by weight, of from about 2.3% to about 25%.
11. The process of claim 10 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about
16.5 seconds to about 30 seconds at an equivalent temperature of
from about 126.degree. C. to about 149.degree. C.
12. The process of claim 11 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about 18
seconds to about 28 seconds at an equivalent temperature of from
about 137.degree. C. to about 149.degree. C.
13. The process of claim 10 wherein said liquid extract is a
non-hydrolysed liquid having a pyridine to 5-methyl-2-furfurylfuran
ratio value of from about 4:1 to about 20:1 and a solids content,
by weight, of from about 3.5% to about 10%.
14. The process of claim 13 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about
16.5 seconds to about 30 seconds at an equivalent temperature of
from about 126.degree. C. to about 149.degree. C.
15. The process of claim 14 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about 18
seconds to about 28 seconds at an equivalent temperature of from
about 137.degree. C. to about 1490 C.
16. The process of claim 13 wherein said liquid extract is a
non-hydrolysed liquid having a pyridine to 5-methyl-2-furfurylfuran
ratio value of from about 4.5:1 to about 15:1 and a solids content,
by weight, of from about 3.5% to about 8%.
17. The process of claim 16 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about
16.5 seconds to about 30 seconds at an equivalent temperature of
from about 126.degree. C. to about 149.degree. C.
18. The process of claim 17 wherein said liquid extract is
subjected to heat treating for an equivalent time of from about 18
seconds to about 28 seconds at an equivalent temperature of from
about 137.degree. C. to about 149.degree. C.
19. The process of claim 7 wherein the step of providing said
liquid extract comprises producing a coffee extract using an
extraction process that is operated at: a.) a flow rate ratio of
kilograms water per minute to kilograms of coffee from about 0.1:1
to about 0.5:1; b.) a water front speed of from about 5 cm to about
25 cm per minute; c.) a draw-off ratio of mass of extract to mass
of coffee from about 4:1 to about 10:1; and d.) a yield of from
about 17 to about 35%.
20. The process of claim 19, said process being operated at less
than 149.degree. C.
21. The process of claim 20, said process being operated at a
temperature of from about 65.degree. C. to about 99.degree. C.
22. The process of claim 21, said process being operated at a
temperature of from about 82.degree. C. to about 93.degree. C.
23. The process of claim 19, said processing being operated to
achieve a draw-off ratio of mass of extract to mass of coffee from
about 5.5:1 to about 8: 1, and a yield of from about 17 to about
30%.
24. The process of claim 23, said processing being operated to
achieve a draw-off ratio of mass of extract to mass of coffee from
about 6.5:1 to about 7:1, and a yield of from about 23 to about
27.5%.
25. A method assessing the quality of a coffee concentrate, said
method comprising the steps of: a.) providing a coffee concentrate;
b.) providing a fresh brewed coffee brewed from the same coffee
used to produce the concentrate; and c.) determining the furfuryl
acetate to 4-ethyl guaiacol ratio value of the coffee concentrate
and the furfuryl acetate to 4-ethyl guaiacol ratio value of the
fresh brewed coffee.
26. The method of claim 25, comprising the further step of
comparing the furfuryl acetate to 4-ethyl guaiacol ratio value of
the coffee concentrate and the furfuryl acetate to 4-ethyl guaiacol
ratio value of the fresh brewed coffee.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application No. 60/345,234, filed Oct. 19, 2001.
TECHNICAL FIELD
[0002] The present invention relates to liquid coffee concentrates,
methods of producing and assessing the quality of liquid coffee
concentrates and products containing said concentrates.
BACKGROUND OF THE INVENTION
[0003] Consumers produce the traditional "pot of coffee" by
extracting the desired components of roast and ground coffee using
an automatic drip coffee maker (ADC) or other form of brewer.
Although the flavor and aroma of such a coffee beverage is highly
desired and appreciated, the inconvenience of the brewing process
has lead to the development of instant coffee and coffee
concentrate products that allow the consumer to quickly make a
single cup of coffee. Unfortunately, the production processes used
to produce such coffee products result in finished products having
ratios of flavor and aroma components that are different from fresh
brewed coffee. As a result, coffee beverages produced from such
concentrated products do not have the highly desired flavor and
aroma of fresh brewed coffee.
[0004] Since the flavor and aroma of fresh brewed coffee is
especially desired by consumers, attempts have been made to improve
the flavor and aroma of products made from coffee concentrates.
Such attempts include incorporating volatile aroma flavor
components into the finished concentrates, and the intensification
of such components by the application of thermal energy. While such
attempts are appreciated, there remains a need for a liquid coffee
concentrate having the same ratios of flavor and aroma components
as that of fresh brewed coffee brewed from the same coffee used to
produce the coffee concentrate.
SUMMARY OF THE INVENTION
[0005] Applicant's invention relates to a liquid coffee concentrate
having a furfuryl acetate to 4-ethyl guaiacol ratio value that is
from about 50% to about 210% of the furfuryl acetate to 4-ethyl
guaiacol ratio value of fresh brewed coffee brewed with the same
coffee used to produce said coffee concentrate. Applicants also
claim methods of producing and assessing the quality of coffee
concentrates and products containing said concentrates.
DETAILED DESCRIPTION
[0006] A. Definitions
[0007] As used herein, the term "coffee product" includes, but is
not limited to coffee concentrates, coffee extracts and fresh
brewed coffee.
[0008] As used herein, the term "coffee concentrate" means a coffee
extract that has undergone additional processing, such as thermal
treatment.
[0009] As used herein, the term "pyridine to
5-methyl-2-furfurylfuran ratio value" refers to the number that is
obtained when a coffee product's pyridine and
5-methyl-2-furfurylfuran peak area values are determined according
to Applicants' analytical test and said resulting pyridine's peak
area value is divided by said 5-methyl-2-furfurylfuran's peak area
value.
[0010] As used herein, the term "furfuryl acetate to 4-ethyl
guaiacol ratio value" refers to the number that is obtained when a
coffee product's furfuryl acetate and 4-ethyl guaiacol peak area
values are determined according to Applicants' analytical test and
said resulting furfuryl acetate's peak area value is divided by
said 4-ethyl guaiacol's peak area value.
[0011] As used herein, the term "unit operation" includes, but is
not limited to, equipment used to transfer heat such as heaters and
coolers; holders; and transfer lines.
[0012] All percentages and ratios are calculated by weight unless
otherwise indicated.
[0013] As used herein, the articles a and an, when used in a claim,
are understood to mean at least one of the components that are
claimed or described.
[0014] Publications, patents, and patent applications are referred
to throughout this disclosure. All references cited herein are
hereby incorporated by reference in their entirety.
[0015] B. Coffee Concentrate Characteristics and Preparation
[0016] The quality of any ready-to-use coffee product, made from a
coffee concentrate, is dependent on the properties of the
concentrate. Although coffee concentrates contain innumerable aroma
and flavor components, Applicants discovered that the flavor and
aroma of products made from concentrate approaches that of fresh
brewed coffee when the concentrate's ratio value of furfuryl
acetate to 4-ethyl guaiacol approaches the furfuryl acetate to
4-ethyl guaiacol ratio value of fresh brewed coffee brewed from the
same coffee used to produce the concentrate.
[0017] In addition to discovering the correlation between the ratio
value of furfuryl acetate to 4-ethyl guaiacol, and flavor and
aroma, Applicants discovered that a coffee concentrate's ratio of
furfuryl acetate to 4-ethyl guaiacol can be adjusted by the
application of thermal energy to the concentrate. While evaluating
the suitability of thermal processing, Applicants discovered that
the entire, rather than just the hold tube portion, of a time and
temperature profile must be considered. Applicants also recognized
that the suitability of any set of thermal processing conditions is
not only time and magnitude dependent but rate dependent as well.
As a result, more common thermal processing descriptors such as Fo
are insufficient to describe the thermal processing conditions that
will result in the flavor and aroma improvements of Applicants'
invention. Thus, Applicants' processing conditions are described in
terms of equivalent times and temperatures, as thermal processing
conditions that are time, magnitude and rate dependent can be
effectively and efficiently described by these descriptors.
[0018] A detailed description of Applicants' coffee concentrate and
processes of making said concentrate is set forth in detail
below.
[0019] 1. Coffee Concentrate
[0020] Embodiments of Applicants' coffee concentrate have a ratio
value of furfuryl acetate to 4-ethyl guaiacol that is from about
50% to about 210% of the ratio value of furfuryl acetate to 4-ethyl
guaiacol of fresh brewed coffee brewed with the same coffee used to
produce said coffee concentrate. Other embodiments of Applicants'
coffee concentrate have a ratio value of furfuryl acetate to
4-ethyl guaiacol that is from about 65% to about 150% of the ratio
value of furfuryl acetate to 4-ethyl guaiacol of fresh brewed
coffee brewed with the same coffee used to produce said coffee
concentrate. Still other embodiments of Applicants' coffee
concentrate have a ratio value of furfuryl acetate to 4-ethyl
guaiacol that is from about 80% to about 120% of the ratio value of
furfuryl acetate to 4-ethyl guaiacol of fresh brewed coffee brewed
with the same coffee used to produce said coffee concentrate.
[0021] 2. Process of Making Coffee Concentrate
[0022] Coffee extracts that can be thermally processed according to
Applicants' process can be prepared by any suitable process used to
produce a coffee extract. Preferably, said coffee extracts are
non-hydrolysed liquids having pyridine to 5-methyl-2-furfurylfuran
ratio values of from about 3:1 to about 25:1 and solids contents of
from about 2.3% to about 25% by weight. Other preferred
non-hydrolysed liquid coffee extracts include those extracts having
a pyridine to 5-methyl-2-furfurylfuran ratio value of from about
4:1 to about 20:1 and a solids content of from about 3.5% to about
10% by weight; and those extracts having a pyridine to
5-methyl-2-furfurylfuran ratio value of from about 4.5:1 to about
15:1 and a solids content of from about 3.5% to about 8% by
weight.
[0023] Suitable methods of producing a coffee extract include, but
are not limited to, extracting said concentrate from roasted and
ground, caffeinated or decaffeinated coffee using a continuous flow
column. Said columns are typically stainless steel vertical columns
having a height-to-diameter ratio greater than or equal to 6:1 and
a perforated top and bottom retainer to permit the transport of
feed water while simultaneously keeping coffee granules between the
retainers. Suitable columns can be obtained from Niro A/S of
Soeborg, Denmark.
[0024] Suitable extraction conditions include, but are not limited
to, operating the extraction process at a temperature less than
149.degree. C. and achieving a flow rate ratio of kilograms water
per minute to kilograms of coffee from about 0.1:1 to about 0.5:1,
a water front speed of from about 5 cm to about 25 cm per minute, a
draw-off ratio of mass of extract to mass of coffee from about 4:1
to about 10:1; and a yield of from about 17% to about 35%. Other
suitable extraction conditions include operating the extraction
process at a temperature less than 149.degree. C. and achieving a
flow rate ratio of kilograms water per minute to kilograms of
coffee from about 0.2:1 to about 0.4: 1, a water front speed of
from about 12.5 cm to about 25 cm per minute, a draw-off ratio of
mass of extract to mass of coffee from about 5.5:1 to about 8:1;
and a yield of from about 17% to about 30%; and operating the
extraction process at a temperature less than 149.degree. C. and
achieving a flow rate ratio of kilograms water per minute to
kilograms of coffee from about 0.25:1 to about 0.36: 1, a water
front speed of from about 12.5 cm to about 15.2 cm per minute, a
draw-off ratio of mass of extract to mass of coffee from about
6.5:1 to about 7:1; and a yield of from about 23% to about 27.5%.
Still other suitable extraction conditions include operating the
extraction process at a temperature range of from about 65.degree.
C. to about 99.degree. C. or from about 82.degree. C. to about
93.degree. C. and achieving any set of flow rate, water front
speed, draw-off ratio and yield parameters detailed previously.
[0025] After a suitable extract is obtained, said extract is
thermally processed. Suitable thermal processing equipment includes
but is not limited to, a MicroThermics model 25DH UHTIHTST unit.
Said equipment can be obtained from MicroThermics Inc. Raleigh,
N.C. U.S.A. Regardless of the thermal processing equipment that is
employed to thermally process a coffee extract, said equipment must
be operated such that the extract is heat treated for an equivalent
time from about 15 seconds to about 35 seconds at an equivalent
temperature of from about 115.degree. C. to about 149.degree. C.;
preferably said equipment must be operated such that the extract is
heat treated for an equivalent time from about 16.5 seconds to
about 30 seconds at an equivalent temperature of from about
126.degree. C. to about 149.degree. C.; and most preferably said
equipment must be operated such that the extract is heat treated
for an equivalent time from about 18 seconds to about 28 seconds at
an equivalent temperature of from about 137.degree. C. to about
149.degree. C. Additionally, when an extract is heat treated for an
equivalent time and temperature combination such that the following
mathematical relationship is true, the resulting concentrate is
sufficiently sterile to be aseptically packaged. 1 Log ( Equivalent
Time ) log ( 10.1 ) - ( Equivalent Temperature - 135 .degree. C . )
10.5
[0026] The resultant coffee concentrate used may be used
immediately, in the same manner as conventional coffee
concentrates, to form coffee containing products or may be packaged
according to known methods for later use.
Analytical Methods
[0027] 1. Method For Calculating Equivalent Time and
Temperature
[0028] a.) Obtain time and temperature data for the thermal process
of interest. This data must include at least 10 (time, temperature)
data points for each unit operation that is part of said thermal
process.
[0029] b.) Interpolate the time and temperature data obtained in
Step (a) above using the Cubic Spline Interpolation Method found on
pages143 to 150 of Numerical Analysis, by Richard L. Burden, J.
Douglas Faires, Sixth Edition, 1997 Brooks/Cole Publishing Company,
ISBN 0-534-95532-0 to obtain a time/temperature profile.
[0030] c.) Evaluate G.sub.Total using the following equation and
numerical integration according to the Romberg Method found on
pages 209 to 213 of Numerical Analysis, Richard L. Burden, J.
Douglas Faires, Sixth Edition, 1997 Brooks/Cole Publishing Company,
ISBN 0-534-95532-0: 2 G Total j := 0 time final exp [ - 1 Ea j 1000
R ( T emp ( t ) + 273.15 ) ] dt
[0031] for the following activation energies (Arrhenius model):
[0032] Ea=(50, 70, 90, 110, 130, 150, 170, 190, 210, 230, 250, 270,
290, 310, 330)
[0033] Where said activation energies are expressed in kJ/mol,
R=8.314 J/mol. K, time is expressed in seconds and temperature is
expressed in .degree. C.
[0034] d.) Using the equation below: 3 log ( G Total ) = log ( t E
) - 1000 R l n ( 10 ) T E Ea
[0035] transform the (G.sub.Total, Ea) data points into a linear
equation, and then use linear regression such that:
[0036] Equivalent_Time:=10.sup.intercept(Ea,
log(G.sup..sub.Total.sup.)) 4 Equivalent_Temperature := - 1000 R l
n ( 10 ) slope ( Ea , log ( G Total ) ) - 273.15
[0037] where the Equivalent Time is expressed in seconds and the
Equivalent Temperature in .degree. C.
[0038] 2. Method of Determining The Percent Solids of Fresh Brewed
Coffee, Coffee Extracts and Coffee Concentrates (Analysis must be
done in triplicate).
[0039] a.) Weigh a clean, empty vessel to the nearest 0.0001
gram.
[0040] b.) Place 25 ml of test sample in the vessel.
[0041] c.) Weigh the vessel containing the sample to the nearest
0.0001 gram.
[0042] d.) Place the vessel in a convection oven at 105.degree. C.
and dry to a constant weight.
[0043] e.) Remove the vessel from the oven and then weigh the
vessel to the nearest 0.0001 gram.
[0044] f.) Calculate % solids by weight as follows: 5 % Solids = [
( DrySampleWeight + VesselWeight ) - VesselWeight (
InitialSampleWeight + VesselWeight ) - VesselWeight ] .times.
100
[0045] 3. Method of Preparing Fresh Brewed Coffee For Use In
Analytical Method No. 5 below.
[0046] Fresh brewed coffee is made using the same coffee used to
produce the coffee concentrate of interest.
[0047] a.) Materials and Apparatus:
[0048] i.) 33.3 g of the roast and ground coffee having an average
particle size of 600 to 850 microns.
[0049] ii.) 1420 mls of distilled water.
[0050] iii.) Mr. Coffee.RTM. model Accel.TM. automatic drip coffee
brewer.
[0051] iv.) Mr. Coffee.RTM. Model # UF100 coffee filter.
[0052] b.) Brewing Procedure
[0053] i.) Place the coffee in a filter and then place the filter
in the brewer.
[0054] ii.) Pour the distilled water into the coffee brewer and
then brew according to the Mr. Coffee.RTM. brewing directions.
[0055] iii.) After completing Step (b)(ii), separate the brewed
coffee into 2 aliquots. Immediately freeze one aliquot, and use the
second aliquot to determine, according to Method No. 2 above, the %
solids, by weight, of the coffee.
[0056] iv) Prior to testing according to Method No. 5 below, thaw
the frozen sample and dilute said sample to a concentration of
0.55% solids by weight. After thawing and diluting the sample, the
sample must be analyzed according to Method No. 5 below within 30
minutes.
[0057] 4. Method of Preparing Coffee Extracts And Concentrates For
Use In Analytical Method No. 5 below.
[0058] a.) Within 30 minutes after an extract or concentrate is
produced, two aliquots of the extract or concentrate must be
obtained. One aliquot is immediately packaged in a glass container
that is then sealed and frozen. The % solids, by weight, of the
second aliquot is immediately determined according to Method No. 2
above.
[0059] b.) Prior to testing according to Method No. 5 below, thaw
the frozen sample and dilute said sample to a concentration of
0.55% solids by weight. After thawing and diluting the sample, the
sample must be analyzed according to Method No. 5 below within 30
minutes.
[0060] 5. Method For Determining Furfuryl Acetate:4-ethyl Guaiacol
Ratio Values And Pyridine:5-Methyl-2-Furfurylfuran Ratio Values
(Analysis Must Be Done In Triplicate).
[0061] Apparatus:
[0062] 1. 100 ml headspace sampling vial cleaned with distilled
water and heated in a muffle furnace at 500.degree. C. for 24
hours.
[0063] 2. Thermostated container capable of being thermostated to
at least 5.degree. C.
[0064] 3. Digital magnetic stirrer capable of a stirring speed of
at least 300 rpm.
[0065] 4. A clean 1 cm Twister.TM. bar having a coating thickness
of 0.5 mm (stir bar coated with polydimethylsiloxane) supplied by
the Gerstel GmbH & Co. KG of Mulheim an der Ruhr, Germany.
[0066] 5. A clean modified trap consisting of a 1-ml syringe barrel
with a threaded glass tip packed with deactivated glass wool as
described on page 204 of S. Maeno and P. A. Rodriguez, "Simple and
versatile injection system for capillary gas chromatographic
columns performance evaluation of a system including mass
spectrometric and light-pipe Fourier-transform infrared detection",
J. Chromatogr. A 1996, 731, 201-215.
[0067] 6. Gas Chromatograph (GC): Hewlett Packard (HP) model 6890:
the GC is modified to accommodate the trap of (5) above as
described on page 203 of S. Maeno and P. A. Rodriguez, "Simple and
versatile injection system for capillary gas chromatographic
columns performance evaluation of a system including mass
spectrometric and light-pipe Fourier-transform infrared detection",
J. Chromatogr. A 1996, 731, 201-215.
[0068] 7. GC column: Durabond-5.RTM. Mass Spectrometer (30 meters
in length, 0.252 mm column ID and 1.0 .mu.m film thickness)
obtained from J&W Scientific of Folsom, Calif., USA.
[0069] 8. Carrier gas, helium, capable of being delivered at a 2
ml/min. flow rate.
[0070] 9. Model HP 5973 Mass Selective Detector obtained from
Hewlett Packard, Santa Clarita, Calif., USA having a source
temperature of about 230.degree. C., and a MS Quad temperature of
about 150.degree. C.
[0071] 10. Chemstation software obtained from Hewlett Packard,
Santa Clarita, Calif., USA and computer capable of running said
software.
[0072] 11. MS spectral libraries of John Wiley & Sons and the
National Institute of Standards and Technology (NIST), purchased
and licensed through Hewlett Packard.
[0073] Procedure:
[0074] 1. Thermostat the container (Apparatus # 2) to 5.degree.
C.
[0075] 2. Add 50 mls of the sample solution (prepared according to
Methods 3 or 4 above) into the 100 ml headspace vial.
[0076] 3. Add 50 .mu.ls of an internal standard solution
(2-heptanone, 500 ppm in water) to the 100 ml headspace vial.
[0077] 4. Place the Twister.TM. bar into the 100 ml headspace vial
and seal the vial with a crimp seal.
[0078] 5. Place the 100 ml headspace vial from Step (4) above into
the thermostated container
[0079] 6. Place the thermostated container containing the 100 ml
headspace vial on to the digital magnetic stirrer and stir at 300
rpm for 45 minutes.
[0080] 7. After Step (6) above is completed, remove the Twister.TM.
bar from the 100 ml sample vial and rinse the bar with 4 mls of
chilled (5.degree. C.) Milli-Q.TM. water, and then blott the bar
dry with Kimwipes.TM..
[0081] 8. After Step (7) above is completed place the Twister.TM.
bar into the trap (Apparatus 5).
[0082] 9. Start sequence of sample loading and analysis.
[0083] i) cool the pre-column to a temperature equal to or less
than -90.degree. C.
[0084] ii) next, connect the trap to a helium flow having a flow
rate of 15 ml/min
[0085] iii) then heat the trap to 200.degree. C. for 8 minutes to
desorb the trapped flavor compounds.
[0086] 10. After Step (9) is complete, the GC-MS analysis is run as
follows. The following temperature program is used:
[0087] i) an initial temperature of 50.degree. C. which is held for
1 minute,
[0088] ii) increase the initial temperature at a rate of 4.degree.
C./min until a temperature of 250.degree. C. is reached,
[0089] iii) hold at 250.degree. C. for 1 minute.
[0090] 11. Identify the peaks corresponding to furfuryl acetate,
4-ethyl guaiacol, pyridine and 5-methyl-2-furfurylfuran using the
MS spectral libraries of John Wiley & Sons and the National
Institute of Standards and Technology (NIST), purchased and
licensed through Hewlett Packard.
[0091] 12. Integrate the chromatographic peaks corresponding to the
ions (listed below) for each identified compound using the
Chemstation software obtained from Hewlett Packard, Santa Clarita,
Calif., USA.
[0092] i.) Pyridine (PYR) ion having a mass to charge ratio of
52
[0093] ii.) Furfuryl Acetate (FA) ion having a mass to charge ratio
of 140
[0094] iii.) 5-Methyl-2-Furfurylfuran (5MFF) ion having a mass to
charge ratio of 162
[0095] iv.) 4-Ethyl Guaiacol (EG) ion having a mass to charge ratio
of 137
[0096] 13. For a test sample obtain the ratio values of furfuryl
acetate to 4-ethyl guaiacol and pyridine to
5-methyl-2-furfurylfuran as follows:
[0097] i) ratio value of FA:EG=peak area FA ion/peak area EG
ion
[0098] ii) ratio value of PYR:5MFF=peak area PYR ion /peak area
5MFF ion
REFERENCES
[0099] 1. E. Baltussen, P. Sandra, F. David and C. Cramers, "Stir
Bar Sorptive Extraction (SBSE), a Novel Extraction Technique for
Aqueous Samples: Theory and Principles", J. Microcolumn
Separations, 11(10), 737-747, 1999.
[0100] 6. Color Measurement (Analysis Must Be Done In
Triplicate).
[0101] a.) Apparatus
[0102] i) Hunter D25L-9000 colorimeter with a DP9000 processor
supplied by Hunter Associates Laboratory Inc. of Reston, Va.
U.S.A.
[0103] ii) Straight edge
[0104] iii) Aluminum sample cup 2.5 cm high and having an outside
diameter of 12.4 cm. The cup contains a cavity having a depth of
1.9 cm and an inside diameter of 11.8 cm.
[0105] b.) Procedure
[0106] i) Place a sufficient amount of coffee, having an average
particle size of 600 to 850 microns, in the sample cup to overfill
the sample cup.
[0107] ii) Level the coffee in the sample cup, using the straight
edge, such that the coffee sample is uniformly even with the top of
the cup.
[0108] iii) Place the cup in the Hunter D25L-9000 calorimeter and
operate the instrument according to the manufacturer's
instructions.
[0109] iv) Record the L color value.
EXAMPLES
[0110] The following examples are illustrative of the present
invention but are not meant to be limiting thereof.
Example 1
[0111] 3.9 Kg of an all Arabica coffee French roasted and ground is
blended with 2.57 Kg of a French roasted and ground Arabica/Robusta
blend. This coffee is loaded into an extraction column about 6
inches in diameter and four and a half feet tall. The cap, which
includes an exit port with a screen to contain the R&G coffee,
is placed on the column. Nitrogen gas is used to flush air from the
extraction system. Deaerated distilled water heated to 82.degree.
C. is pumped counter-currently through the bed of coffee at about
1.9 liter/minute. 45.2 Kg of extract containing 3.89% solids is
obtained and cooled to about 29.degree. C. This extract is filtered
through a 10 micron pleated glass filter cartridge to remove
sediment and then heat treated for an equivalent time of 21.2
seconds at an equivalent temperature of 145.degree. C. using a
MicroThermics model 25DH UHT/HTST unit to produce a
concentrate.
[0112] Pre-thermal treatment and post thermal treatment samples of
the concentrate are tested according to Applicants' analytical
methods. The pre-thermal treatment sample is found to have a
pyridine to 5-methyl-2-furfurylfuran ratio value of 9.4, and the
samples are found to have ratio values of furfuryl acetate to
4-ethyl guaiacol listed below.
1 Furfuryl Acetate:4-Ethyl Guaiacol Sample Ratio Value Fresh Brewed
Standard 0.62 Pre-thermal treatment sample 1.75 Post thermal
treatment sample 0.60
Example 2
[0113] 3.6 Kg of an all Arabica roasted and ground coffee having
roast color of 15.5 L is extracted as in Example 1 at a flow rate
of about 1.8 liters/minute, yielding 26 Kg of concentrate
containing 3.59% solids. The extract is heat treated for an
equivalent time of 26.5 seconds at an equivalent temperature of
141.degree. C. using a MicroThermics model 25DH UHT/HTST unit to
produce a concentrate.
[0114] Pre-thermal treatment and post thermal treatment samples of
the concentrate are tested according to Applicants' analytical
methods. The pre-thermal treatment sample is found to have a
pyridine to 5-Methyl-2-Furfurylfuran ratio value of 10.2, and the
samples are found to have ratio values of furfuryl acetate to
4-ethyl guaiacol listed below.
2 Furfuryl Acetate:4-Ethyl Guaiacol Sample Ratio Value Fresh Brewed
Standard 0.83 Pre-thermal treatment sample 3.06 Post thermal
treatment sample 1.44
Example 3
[0115] 6.64 Kg of a roasted and ground decaffeinated Arabica and
Robusta coffee blend having roast color of 18.1 L is extracted as
in Example 1 at a flow rate of about 1.8 liters/minute, yielding
44.4 Kg of extract containing 3.56% solids. The extract is heat
treated for an equivalent time of 25.6 seconds at an equivalent
temperature of 141.degree. C. using a MicroThermics model 25DH
UHT/HTST unit to produce a concentrate.
[0116] Pre-thermal treatment and post thermal treatment samples of
the concentrate are tested according to Applicants' analytical
methods. The pre-thermal treatment sample is found to have a
pyridine to 5-Methyl-2-Furfurylfuran ratio value of 12.7, and the
samples are found to have ratio values of furfuryl acetate to
4-ethyl guaiacol listed below.
3 Furfuryl Acetate:4-Ethyl Guaiacol Sample Ratio Value Fresh Brewed
Standard 0.47 Pre-thermal treatment sample 1.12 Post thermal
treatment sample 0.42
* * * * *