U.S. patent application number 10/798472 was filed with the patent office on 2004-11-11 for composition for application to a film for holding a food product.
Invention is credited to Samuels, Brian R., Shoop, John, Underwood, Gary L..
Application Number | 20040224174 10/798472 |
Document ID | / |
Family ID | 33032673 |
Filed Date | 2004-11-11 |
United States Patent
Application |
20040224174 |
Kind Code |
A1 |
Shoop, John ; et
al. |
November 11, 2004 |
Composition for application to a film for holding a food
product
Abstract
A coating composition for application to a food packaging film
is disclosed. The resulting film can be used as a tubular food
casing that, after cooking or heating, imparts a brown color to a
foodstuff encased in the casing.
Inventors: |
Shoop, John; (Manitowoc,
WI) ; Underwood, Gary L.; (Manitowoc, WI) ;
Samuels, Brian R.; (Frankfort, IL) |
Correspondence
Address: |
MARSHALL, GERSTEIN & BORUN LLP
6300 SEARS TOWER
233 S. WACKER DRIVE
CHICAGO
IL
60606
US
|
Family ID: |
33032673 |
Appl. No.: |
10/798472 |
Filed: |
March 11, 2004 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60501339 |
Sep 8, 2003 |
|
|
|
60454444 |
Mar 13, 2003 |
|
|
|
Current U.S.
Class: |
428/507 ;
428/532 |
Current CPC
Class: |
C08J 2323/12 20130101;
Y10T 428/1393 20150115; C08J 7/043 20200101; B29C 59/14 20130101;
A22C 13/00 20130101; Y10T 428/1355 20150115; A22C 2013/0046
20130101; B29C 2035/0827 20130101; Y10T 428/1324 20150115; B29C
59/16 20130101; B29C 59/085 20130101; Y10T 428/3188 20150401; B29L
2023/002 20130101; C08J 7/056 20200101; C08J 2477/00 20130101; B29C
59/103 20130101; Y10T 428/139 20150115; Y10T 428/31855 20150401;
A22C 13/0013 20130101; Y10T 428/31971 20150401; B29C 59/08
20130101; Y10T 428/1352 20150115; B29C 2035/085 20130101; Y10T
428/1303 20150115; C08J 7/048 20200101; Y10T 428/3175 20150401;
B29C 59/10 20130101; Y10T 428/13 20150115; Y10T 428/1359 20150115;
B29C 59/00 20130101; B29C 59/142 20130101; B29C 59/165 20130101;
B29C 2035/0877 20130101 |
Class at
Publication: |
428/507 ;
428/532 |
International
Class: |
B32B 023/04 |
Claims
What is claimed is:
1. A liquid composition for application to a food packaging film,
said composition comprising: (a) about 20% to about 47%, by weight,
of a browning agent; (b) about 0.05% to about 2%, by weight, of a
viscosity-modifying agent; (c) 0% to about 10%, by weight, of a
surfactant, a polyol, or mixture thereof; (d) 0% to about 3%, by
weight, of a pharmaceutically acceptable salt; and (e) water, said
composition having a pH of about. 2 to about 6.5 and capable of
transferring the browning agent of the composition from the food
packaging film to a foodstuff packaged in the food packaging
film.
2. The composition of claim 1 further comprising a flavoring
agent.
3. The composition of claim 1 wherein the composition comprises
about 25% to about 40%, by weight, of the browning agent.
4. The composition of claim 1 wherein the composition comprises
about 30% to about 35%, by weight, of the browning agent.
5. The composition of claim 1 wherein the browning agent is capable
of undergoing a Maillard reaction with meat proteins.
6. The composition of claim 1 wherein the browning agent comprises
a pyrolysis product from combustion of a sugar, a starch, or a
mixture thereof.
7. The composition of claim 6 wherein the browning agent comprises
aldehydes.
8. The composition of claim 6 wherein the browning agent comprises
hydroxyacetaldehyde.
9. The composition of claim 1 wherein the browning agent comprises
a pyrolysis product from combustion of wood or a cellulose.
10. The composition of claim 2 wherein flavoring agent comprises a
phenol, an acid, or a mixture thereof.
11. The composition of claim 1 wherein the composition further
comprises caramel, beet extract, malt, bixin, annatto, or a mixture
thereof.
12. The composition of claim 1 wherein the composition comprises
about 0.05% to about 1%, by weight, of the viscosity-modifying
agent.
13. The composition of claim 1 wherein the composition comprises
about 0.10% to about 0.25%, by weight, of the viscosity-modifying
agent.
14. The composition of claim 1 wherein the viscosity-modifying
agent comprises a cellulosic or a gum.
15. The composition of claim 1 wherein the viscosity-modifying
agent comprises a cellulose ether.
16. The composition of claim 15 wherein the viscosity-modifying
agent comprises a water-soluble anionic cellulose ether.
17. The composition of claim 1 wherein the viscosity-modifying
agent is selected from the group consisting of cellulose,
methylcellulose, hydroxypropylcellulose, starch, chitin,
carrageenan, konjac, guar gum, xanthan gum, alginic acid and
derivatives thereof, agar, pectin, gelatin, methylcellulose,
hydroxypropylmethylcellulose, hydroxypropylcellulose, ethyl
methylcellulose, hydroxyethylcellulose, ethyl
hydroxyethylcellulose, carboxymethylcellulose, carboxymethyl
hydroxyethylcellulose, and mixtures thereof.
18. The composition of claim 1 wherein the composition comprises
about 1% to about 8% of a surfactant, a polyol, or mixture thereof,
by weight of the composition.
19. The method of claim 1 wherein the composition comprises about
2% to about 5% of a surfactant, a polyol, or mixture thereof, by
weight of the composition.
20. The method of claim 1 wherein the composition comprises a
surfactant.
21. The method of claim 1 wherein the composition comprises a
polyol.
22. The method of claim 1 wherein the composition comprises a
surfactant and a polyol.
23. The method of claim 1 wherein the surfactant or glycol is
selected from the group consisting of calcium stearoyl lactylate, a
diglyceride, dioctyl sodium sulfosuccinate, lecithin, a
monoglyceride, polysorbate 60, polysorbate 65, polysorbate 80,
sodium lauryl sulfate, sodium stearoyl lactylate, sorbitan
monostearate, propylene glycol, glycerol, and mixtures thereof.
24. The composition of claim 1 wherein the browning agent comprises
hydroxyacetaldehyde; the viscosity-modifying agent is selected from
the group consisting of xanthan gum, konjac gum, a methylcellulose,
and mixtures thereof; and the surfactant or glycol is selected from
the group consisting of propylene glycol, dioctyl sulfosuccinate,
glycerol, and mixtures thereof.
25. The composition of claim 1 comprising about 0.5% to about 2.5%,
by weight, of a salt.
26. The composition of claim 1 comprising about 1% to about 2%, by
weight, of a salt.
27. The composition of claim 1 wherein the salt comprises sodium
chloride.
28. The composition of claim 1 having a pH of about 4 to about
6.
29. A food packaging film having a composition of claim 1 applied
to a food contact surface of the film.
30. The film of claim 29 wherein the composition is applied to the
food contact surface of the film in an amount of about 0.1 to about
1.5 milligrams of the composition per square centimeter of the food
contact surface.
31. A method of preparing and processing a foodstuff encased in a
casing comprising the steps of: (a) providing a casing suitable for
a foodstuff; (b) applying a composition of claim 1 to a surface of
the casing that contacts a foodstuff; (c) stuffing a foodstuff into
the casing of step (b); and (d) heating the stuffed casing of step
(c) at a sufficient temperature and for a sufficient time to
process the foodstuff.
32. The method of claim 31 wherein heating step (d) is performed
within four hours performing stuffing step (c).
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional
patent application 60/501,339, filed Sep. 8, 2003, and U.S.
provisional patent application Ser. No. 60/454,444, filed Mar. 13,
2003.
FIELD OF THE INVENTION
[0002] The present invention relates to compositions for
application to a film used as packaging material for a food
product, and to food packaging films resulting therefrom. In
particular, the present invention relates to compositions for
application to a tubular food casing, and the resulting casing,
that impart an esthetic brown color to a foodstuff when the
foodstuff is cooked or otherwise heated within the casing.
BACKGROUND OF THE INVENTION
[0003] The use of food casings to encase a food-stuff prior to
further processing, such as smoking, is well known. The traditional
smoking process involves stuffing a foodstuff, such as a sausage,
into a smoke-permeable casing, then hanging the stuffed food
product in a smokehouse. In the smokehouse, wood is burned at low
temperature to generate smoke. Smoking by such a traditional
technique is labor intensive, time consuming (e.g., smoking times
can span several days), and the amount of generated smoke often
fails to comply with pollution laws.
[0004] In order to avoid difficulties associated with the use of
smokehouses, packaged meat products have been placed in a heated
smoke-free environment for cooking. The process of cooking a
foodstuff in a casing by such a method is known as a "cook-in"
process. Films for use in the "cook-in" process are referred to as
"cook-in" films. However, foodstuffs cooked in this smoke-free
manner do not acquire the characteristic brown surface and
wood-smoked flavor of a smoked food product.
[0005] In order to provide the benefits of a smoked food product,
but without the drawbacks of conventional smoking techniques,
liquid smoke was developed decades ago. Liquid smoke is the aqueous
condensate of a natural wood smoke, and contains phenols, acids,
and carbonyl compounds, particularly aldehydes, that react with
meat proteins and brown the meat surface. This browning gives the
appearance of a naturally smoked food product.
[0006] Liquid smoke originally was atomized onto meat products
encased in porous natural gut or cellulose casings prior to cooking
in an oven. The porosity of the casings allowed the liquid smoke to
penetrate the casing and into the meat. In practice, however, it
was difficult to provide a uniform coating of the liquid smoke onto
the food product by this atomization process.
[0007] In view of this difficulty, substantial research was
directed to providing a substantially uniform distribution of
liquid smoke on a food product surface. Some attempts were made to
incorporate a liquid smoke into the meat product itself. However,
this method either provided an insufficient amount of liquid smoke,
and in turn browning, on the surface of the foodstuff or imparted
an excessive smoky flavor to the food product.
[0008] A more successful approach has been to apply a liquid smoke
onto a cellulose casing. Techniques for applying liquid smoke onto
a cellulose casing include dipping or spraying a liquid smoke
solution onto the cellulose casing, such that the liquid smoke on
the interior surface of the casing can be transferred to an encased
foodstuff. Such a treatment can present difficulties during further
processing of the cellulose casings, and, in particular, can
interfere with shirring. Despite these difficulties, a number of
commercially available liquid smoke-treated cellulose casings exist
commercially.
[0009] The permeability and porosity of cellulose casings makes
them compatible for use with liquid smoke. However, these
properties also introduce serious and widely recognized
disadvantages. First, cellulose products are highly permeable to
water vapor, which allows moisture loss during cooking and a
corresponding decrease in overall weight of the product. A reduced
yield of food product results, which is disadvantageous for
commercial reasons. Further, cellulose casings are oxygen
permeable, which leads to spoiling and/or discoloration of the food
product. Because of this latter difficulty, food products cooked in
cellulose casings either are consumed shortly after cooking or are
removed from the casings, then rewrapped in an oxygen-impermeable
barrier casing as quickly as possible after production. This
rewrapping step provides an opportunity for contamination or
infection of the food product, which represents a loss in quality
and shortened shelf life. These additional steps also add to the
cost of the food product.
[0010] To address the disadvantages of permeable cellulose casings,
water and oxygen-impermeable thermoplastic casings were developed.
When using a casing of this type, negligible weight loss occurs
during the production process or during storage and shipping.
Further, the food product remains sterile, provided the casing
remains intact. However, as a result of the impermeability of the
casing, smoke components in either gaseous or liquid form cannot
penetrate the casing. Further, impregnation of thermoplastic
casings with liquid smoke or other coloring additives has not been
successful because thermoplastic casings do not adequately absorb
and store impregnating agents. In order to impart a smoke color to
thermoplastic-encased foodstuffs, it is necessary to remove the
casing and apply an artificial color to the foodstuff, such as by
spraying or dipping techniques, then repackage the foodstuff. These
additional steps not only increase costs, but also increase the
risk of food product contamination.
[0011] There is a recognized need in the art to provide a gas- and
moisture-impermeable casing that can transfer browning and
flavoring agents, such as a liquid smoke or other browning or
flavor agent, to an encased foodstuff during cooking. However, to
date, attempts to solve this problem and provide a commercially
acceptable food product have failed for a variety of reasons. One
approach was to blend a liquid smoke with a resin used for the
inner layer of a plastic casing. This approach was unsuccessful for
a number of reasons, including an insufficient transfer of the
browning or flavoring agent to a meat surface, reaction and
volatilization of the browning or flavoring agent at extrusion
temperatures, and delamination induced by the presence of the
browning or flavoring agent.
[0012] Another approach was to incorporate an absorbent browning or
flavoring agent into the plastic casing. However, such a product
has yet to be adopted commercially, and in practice it is believed
that there is either an insufficient transfer of these agents from
the casing to the foodstuff and/or insufficient retention of these
agents on the surface of the casing.
[0013] A need still exists in the art for a composition that can be
applied to a food packaging film in a sufficient amount to provide
a desired golden brown color, and also being capable of
transferring from the film to the foodstuff to provide the
color.
SUMMARY OF THE INVENTION
[0014] The present invention is directed to compositions for
application to a film used as a packaging material for a food
product. The present invention also is directed to a food packaging
film having a present composition applied to a food contact surface
of the film. The composition is applied to a food contact surface
of a food casing, and imparts an esthetic brown color to a
foodstuff when the foodstuff is processed, i.e., cooked or
otherwise heated, within the casing.
[0015] Therefore, one aspect of the present invention is to provide
a composition for application to a film that can be used as a
casing for a food product. The composition and treated film at
least partially overcome the above-discussed disadvantages in
browning a foodstuff, and provide a useful, commercial packaging
material for a foodstuff.
[0016] Another aspect of the present invention is to provide
compositions that can be applied to a film for use in encasing a
foodstuff, and that effectively impart an esthetic brown color, and
optionally flavor, to the cooked food product.
[0017] Still another aspect of the present invention is to provide
a liquid composition for application to a food packaging film, said
composition comprising:
[0018] (a) about 20% to about 47%, by weight, of a browning
agent;
[0019] (b) about 0.05% to about 2%, by weight, of a
viscosity-modifying agent;
[0020] (c) 0% to about 10%, by weight, of a surfactant, a polyol,
or mixture thereof;
[0021] (d) 0% to about 3% of a pharmaceutically acceptable salt,
e.g., sodium chloride; and
[0022] (e) water,
[0023] said composition having a pH of about 2 to about 6.5, and
capable of transferring the browning agent of the composition from
the food packaging film to a foodstuff packaged in the food
packaging film.
[0024] These and other novel aspects of the present invention will
become apparent from the following detailed description of the
preferred embodiments.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The present invention provides a film for use as a cook-in
casing, wherein the film has a surface for contacting a packaged
foodstuff. The film surface that contacts the foodstuff has a
liquid composition of the present invention applied thereon.
Typically, the composition permeates the film, but may remain, at
least partially, on the surface of the film.
[0026] The composition comprises one or more browning agent, and an
optional flavoring agent, for transfer to a packaged foodstuff.
Prior to application of a present composition to the food contact
surface of the film, the food contact surface preferably is
subjected to a surface activation treatment.
[0027] The present invention relates to the surprising and
unexpected discovery that a liquid composition of the present
invention can be applied to an activated or unactivated surface of
a casing, and the browning agent, and optional flavoring agent, can
be effectively transferred to the encased foodstuff during heating
or cooking. The composition effectively browns, and optionally
flavors, the foodstuff to a consumer acceptable level.
[0028] In preferred embodiments, a present composition is applied
to a film that has been surface activated prior to application of a
present coating composition. The film activation process comprises
subjecting a surface of the film to a surface activation treatment,
then applying a sufficient amount of a liquid composition of the
present invention to the activated surface to impart a
predetermined brown color and, optionally, flavor level to a
foodstuff encased by, and cooked in, the film.
[0029] The film can be prepared from any material suitable for
packaging food and in which a food contained therein can be cooked
or heated. Cook-in films can be single or multilayer films.
Multilayer films include a food contact layer and one or more
additional layers selected from sealant layers, abuse layers, bulk
layers, oxygen barrier layers, moisture barrier layers, tie layers,
and the like.
[0030] Persons skilled in the art are aware of suitable polymer
materials and polymer blends for use in the construction of cook-in
films. Typical polymer materials known in the art include, but are
not limited to, polyolefins, such as polyethylene and higher alpha
olefins, olefin copolymers with vinyl monomers, such as
ethylene/vinyl acetate, ethylene/acrylic acid, or mixtures thereof.
An especially preferred polymer material is a hydrophilic material,
such as a polyamide.
[0031] Polyamides are known in the food packaging art, and include,
but are not limited to, aliphatic polyamides, such as condensates
of aliphatic primary diamines preferably having about 4 to about 8
carbon atoms, and aliphatic dicarboxylic acids preferably having
about 4 to about 10 carbon atoms. An aliphatic copolyamide can be a
homopolymer, or a polymer based on one or more aliphatic diamines
and one or more aliphatic dicarboxylic acids and/or one or more
omega-aminocarboxylic acids or omega-amino-carboxylic lactams.
Examples of suitable dicarboxylic acids include, but are not
limited to, adipic acid, azelaic acid, sebacic acid, and dodecane
dicarboxylic acid.
[0032] The film also can include an additive to facilitate
incorporation of a present coating composition onto or into the
film. Suitable additives include, but are not limited to,
water-soluble or water-swellable materials, such as a starch, a
cellulose, e.g., alpha cellulose, a poly(ethylene oxide), a
poly(vinyl alcohol), a polyacrylic acid, crosslinked
polyvinylpyrrolidone (PVP), and copolymers or mixtures thereof.
Preferred films contain PVP or a mixture thereof.
[0033] The polymer used to manufacture the film also can be blended
with additives that promote melt fracture or modify flow. In some
instances, processing additives are added to control melt fracture.
The levels of these additives are judicially selected to provide
the desired effect. Preferably, the film is heat-shrinkable under
cook-in conditions such that the film conforms tightly to the
cooked food product. Alternatively, the film can be shrunk prior to
cooking by placing the package in a heated environment.
[0034] The surface of the film preferably is treated to increase
the surface area of the film. Methods of surface treatment are
known in the art and include ablation and etching. Alternatively,
the surface can be roughened during extrusion by various methods,
including extrusion through a roughened die or setting the melt and
die temperatures to create a nonuniform or turbulent flow.
[0035] Typically, the film is in the form of a seamless tubular
casing. Tubular casings are prepared by methods known in the art.
Alternatively, the film can be formed as a single sheet, corona
treated, coated with a composition of the present invention, and
then formed into a tube by sealing the edges together. The process
to form a single sheet into a tube by sealing is well known in the
art as back seaming. Back-seaming is used on form and fill
machines.
[0036] The film surface activation treatment can be any suitable
treatment method, such as plasma, flame, corona discharge, UV
irradiation, electron beam irradiation, gamma irradiation, and the
like. The film surface also can be treated chemically by subjecting
the surface to oxidizing or etching agents. A preferred treatment
is corona discharge as disclosed in U.S. Provisional Patent
Application Ser. No. 60/454,444, filed Mar. 13, 2003 and in a U.S.
patent application entitled "A Film Having a Liquid Absorbed
Therein," filed on Mar. 11, 2004, and incorporated herein by
reference.
[0037] It is known to treat a polyolefin material by corona
discharge to improve the wetability of the polyolefin surface.
Typically the polyolefin is treated to increase the surface energy
from about 30-32 dynes up to about 37-40 dynes. The power levels
required to provide such increases in dyne level depend to some
extent on the nature of the material to be treated and any
additives therein, because different materials can respond
differently. For example, polyesters require relatively low power
levels of about 8 to 11 W-m/M.sup.2, whereas polypropylene requires
relatively high power levels of about 22 to about 27 W-m/M.sup.2.
Higher corona treatment levels are considered undesirable because
it is believed a breakdown of the polymer surface occurs and low
molecular weight products are released, which reduces the ability
of the film surface to bond.
[0038] It also is known to treat a polyolefin layer that forms an
interior surface of a tubular food casing by corona discharge. The
corona discharge treatment improves the meat adhesion properties of
the film surface. Typically, polyethylene is treated such that the
surface energy of the film is increased to about 40 to about 50
dynes. A certain degree of adhesion to meat is desirable to avoid a
collection of juices between the meat and film package. Such a
condition is known as "cookout" or purge. However, excessive
adhesion is undesirable because the film does not release cleanly
from the meat surface, and a portion of the meat is pulled away
with the film. This results in a scarred and unsightly meat
appearance.
[0039] Corona treatment of the interior surface of a tubular casing
is described in U.S. Pat. No. 5,296,170, incorporated herein by
reference. Polyamide casing materials, which have a surface energy
of up to about 45 dynes, generally have sufficient meat adhesion
properties and corona treatment is not required. It is believed
that if a polyamide is corona treated, then the resulting film
would adhere excessively to a meat surface, causing the
abovementioned problems.
[0040] The level of surface activation to which a film surface is
subjected varies depending upon the identity of the film and the
particular surface activation treatment. The level of surface
activation necessary for a particular substrate can be determined
by a person of skill in the art by simple experimentation.
Preferably, the surface is activated to a sufficient degree to
retain a composition of the present invention in an amount of about
0.1 to about 1.5, and preferably about 0.2 to about 1.3
mg/cm.sup.2. To achieve the full advantage of the present
invention, the film surface is activated to a sufficient degree to
retain a composition of the present invention in an amount of about
0.3 to about 1.2 mg/cm.sup.2 (milligrams of composition per square
centimeter of film surface).
[0041] It should be understood that it is not necessary to activate
the film surface before application of a present composition. A
present composition can be applied directly to an unactivated film.
Persons skilled in the art are aware of the amount of present
composition, i.e., about 0.1 to about 1.5 mg/cm.sup.2, to apply to
an unactivated film for retention, then transfer, of a browning
agent to an encased food product.
[0042] A present liquid coating composition comprises (a) a
browning agent, (b) a viscosity-modifying agent, (c) an optional
surfactant and/or a polyol, (d) an optional salt, and (e) water,
and has a pH of about 2 to about 6.5. The composition also
optionally comprises a flavoring agent. The composition further can
contain additional optional ingredients, such as a binder or
gelling agent.
[0043] Preferably, for cook-in purposes, the browning agent is a
type that reacts with foodstuff proteins by a Maillard reaction and
produces a brown color characteristic of smoked meat. Browning
agents that react with proteins in this manner are active carbonyl
compounds, such as, but not limited to, aldehydes, e.g.,
hydroxyacetaldehyde, and reducing sugars, such as fructose,
glucose, ribose, lactose, xylose, and the like. A browning agent
that is particularly useful is hydroxyacetaldehyde.
[0044] Preferred browning agents are liquid coloring agents
available under the tradename MAILLOSE.RTM. from Red Arrow Products
Co. LLC, Manitowoc, Wis. MAILLOSE.RTM. contains
hydroxyacetaldehyde, and is prepared from the pyrolysis of sugars
and starches. Traditional liquid smoke products also are useful in
a composition of the present invention. Liquid smoke is a
collection of condensable products from the pyrolysis of wood or
cellulose. Liquid smoke includes active carbonyl compounds as
browning agents and further contains flavoring agents, e.g.,
phenols and acids. Liquid smoke is available under the tradename
CHARSOL.RTM., from Red Arrow Products Co. LLC.
[0045] Preferred browning agents comprise a relatively concentrated
amount of hydroxyacetaldehyde. Especially preferred is a browning
agent comprising about 20 to about 47 wt %, preferably about 25 to
about 40 wt %, and most preferably about 30 to about 35 wt %,
hydroxyacetaldehyde.
[0046] Other optional browning agents unrelated to the pyrolysis of
wood, cellulose, and starches can be used in addition to
hydroxyacetaldehyde and a liquid smoke browning agent. These
browning agents act as dyes to impart additional color to the
cooked foodstuff. Such optional browning agents are well known in
the art and include, but are not limited to, caramel, beet extract,
malt, bixin, annatto, and mixtures thereof.
[0047] A present composition also includes at least one
viscosity-modifying agent. Viscosity-modifying agents suitable for
use in contact with food are well known in the art and include
materials such as cellulosics and gums, like cellulose,
methylcellulose, hydroxypropylcellulose, starch, chitin,
carrageenan, konjac, guar gum, xanthan gum, alginic acid and
derivatives thereof, agar, pectin, gelatin, and the like.
[0048] Preferred viscosity-modifying agents comprise a
water-soluble cellulose ether including, but not limited to,
methylcellulose, hydroxypropylmethylcellulose,
hydroxypropylcellulose, ethyl methylcellulose,
hydroxyethylcellulose, and ethyl hydroxyethylcellulose. More
preferably, the viscosity-modifying agent comprises an anionic
water-soluble cellulose ether including, but not limited to,
carboxymethylcellulose and carboxymethyl hydroxyethylcellulose.
Mixtures of water-soluble cellulose ethers also can be employed.
Particularly preferred viscosity-modifying agents are the
methylcellulose ethers sold under the tradename METHOCEL.RTM..
[0049] Typically, a present composition includes up to about 2 wt
%, preferably up to about 1 wt % of a viscosity-modifying agent. A
more preferred composition includes about 0.05 to about 0.5 wt %,
and most preferably about 0.10 and 0.25 wt %, of a
viscosity-modifying agent.
[0050] A present composition optionally further includes one or
more surfactant and/or polyol. Suitable surfactants are anionic and
nonionic surfactants, including, but not limited to, calcium
stearoyl lactylate, a diglyceride, dioctyl sodium sulfosuccinate,
lecithin, a monoglycerides, polysorbate 60, polysorbate 65,
polysorbate 80, sodium lauryl sulfate, sodium stearoyl lactylate,
sorbitan monostearate, or a mixture thereof. A preferred polyol is
propylene glycol, glycerol, or a mixture thereof.
[0051] The surfactant, glycol, or mixture thereof, in total, is
present in the composition in an amount of up to about 10 wt %, and
preferably about 0.5 to about 8 wt %. To achieve the full advantage
of the present invention the total amount of surfactant, glycol, or
mixture thereof present in the composition is about 1 to about 5 wt
%.
[0052] A present composition also optionally includes a
pharmaceutically acceptable salt, e.g., sodium chloride, in a
sufficient amount to approximate the salt content of a foodstuff
encased in the casing. A salt typically is present in the
composition in an amount of 0 to about 3 wt %, and preferably about
0.5 to about 2.5 wt %. To achieve the full advantage of the present
invention, the composition contains about 1 to about 2 wt % of a
salt.
[0053] It is theorized, but not relied upon herein, that the salt,
in some instances, helps mitigate deep migration of the composition
from the casing into the interior of the encased foodstuff. In the
overall composition, it is important that the composition does not
migrate deeply into the encased foodstuff. By retarding migration
of the composition into the encased foodstuff, the browning agent
remains at or in the vicinity of the surface of the foodstuff and
thereby provides a maximum brown color to the cooked or heated
foodstuff.
[0054] A composition of the present invention is aqueous, and has a
pH of about 2 to about 6.5, and preferably about 3 to about 6.5. To
achieve the full advantage of the present invention, the
composition has a pH of about 4 to about 6. The composition pH
therefore approximates the pH of the encased foodstuff, and reduces
the problem of "purge" during cooking or heating.
[0055] Therefore, an important feature of the present invention is
to provide a composition for application to a surface of a cook-in
film comprising about 20 to about 40 wt % of a browning agent,
preferably hydroxyacetaldehyde, up to about 2 wt % of a
viscosity-modifying agent, optionally up to about 10 wt % of a
surfactant, glycol, or mixture thereof, optionally up to about 3 wt
% of a salt, and having a pH of about 2 to about 6.5.
[0056] An especially preferred composition includes about 20 to
about 40 wt % hydroxyacetaldehyde in combination with a
methylcellulose and a polyol, such as propylene glycol, preferably
up to about 10 wt %, more preferably up to about 5 wt %, polyol. A
preferred composition also contains up to about 1.5 wt % of a salt,
and a pH of about 4 to about 6.
[0057] The composition optionally also can indude other
ingredients, such as, but not limited to, antimicrobial agents,
antioxidants, and stabilizers. An optional ingredient included in
the composition is present in a sufficient amount to perform its
intended function without adversely affecting the composition,
film, or foodstuff.
[0058] The specific identity and amount of the individual
components of the present composition are judiciously selected
after considering the nature of the surface, the material of
construction of the film, and the specific foodstuff to be
packaged. Consideration also is given to a desirable color or
flavor profile of different meat products with a view to consumer
acceptance.
[0059] The level and rate of transfer of composition components
from the film to the foodstuff can be influenced by the
hydrophilic/lipophilic nature of the film surface, the specific
composition, and the foodstuff. While not being bound by any
theory, it is theorized that transfer of hydrophilic composition
materials, e.g., browning agents, to a foodstuff having a
relatively high water content (e.g., whole muscle products, like
hams) is facilitated compared to a foodstuff having a relatively
high fat content (e.g., some types of sausages). It also is
theorized that composition transfer can be modified by the relative
adhesion and retention of the composition to and in the film, and
the absorbency of the composition into the foodstuff. For example,
the present composition can be admixed with an edible oil prior to
application to the film to reduce adhesion and improve
absorbency.
[0060] A present composition can be applied to a surface of the
film by any suitable technique. One suitable, nonlimiting, process
for applying a composition to a tubular casing is described in U.S.
Pat. No. 3,378,379, incorporated herein by reference. This process
is known in the casing art as slugging. The slugging method for
application of a composition to the inside of a casing involves
filling a portion of the casing with the coating material, such
that the slug or coating material generally resides at the bottom
of a "U" shape formed by the casing, and then moving a continuous,
indefinite length of casing such that the slug of coating material
remains confined within the casing, while the casing moves past the
slug and a present coating composition contained within the slug is
applied to its inside wall.
[0061] A modified slugging process also can be used to apply a
present composition to film surface, wherein the slug is trapped
between upper and lower pair of nip rolls. The upper set of rolls
preferably includes a chrome roller and a rubber roller. The rubber
roller typically has a hardness of between about 60 to about 120,
typically between about 70 to about 100, durometer. As the tube
passes between the two sets of rollers, the composition is carried
with the film and the upper set of rolls act as metering rolls.
[0062] Preferably the gap between the roller is set at less than
the thickness of the film, typically at about 50%. This is in
contrast to conventional application techniques where the gap is
set equal to the film thickness plus the desired thickness of the
coating layer. While not wishing to be bound by theory, it is
believed that the pressure created as the film passes between the
rollers assists in forcing the composition into the walls of the
film. Typical levels of absorption are in the order of about 20 to
about 28% by weight.
[0063] Food casings comprising a film coated with a composition of
the present invention can be in any form known in the art, such as
in the form of shirred casing sticks, discrete short segments of
flattened casings, continuous lengths of flattened casing on a
reel, and the like.
[0064] When the film is in the form of a tubular casing, the tube
typically is shirred after application of the present coating
composition. Shirring can be accomplished by conventional shirring
techniques well known to persons skilled in the art.
[0065] Another important feature of the present invention is to
provide a shirred tubular food casing having an interior food
contact surface having a liquid composition of the present
invention applied thereto for transfer to a foodstuff encased
therein. Prior to application of the composition to the surface.,
the surface preferably is subjected to a surface activation
treatment.
[0066] After a present composition is applied to the film, the film
can be used as a casing for a food product. When the film is in the
form of a tubular casing or a shirred casing, the casing can be
stuffed by pushing a meat product through a stuffing horn into the
inside of the tubular casing.
[0067] Another important feature of the invention is to provide a
method of processing, e.g., cooking or heating, a food product
comprising packaging a foodstuff within a film treated with a
composition of the present invention, then heating the packaged
foodstuff for a sufficient time and at a sufficient temperature for
components of the composition to transfer to a surface of the
foodstuff and impart a brown color to the foodstuff.
[0068] As demonstrated hereafter, it is preferred that a foodstuff
is heated or cooked as soon as possible after encasing the
foodstuff in a film having a present composition applied thereto.
It has been found that browning of the cooked or heated foodstuff
is maximized when the encased foodstuff is cooked or heated as soon
as practical after encasing.
[0069] A foodstuff packaged within the film can be cooked by any
suitable method, such as boiling, heating by steam, or in an oven.
Preferably, the packaged foodstuff is cooked as soon as practical
after packaging. As illustrated hereafter, the brown color imparted
to the foodstuff is optimized when the encased foodstuff is
processed within four hours, preferably within two hours, and more
preferably within one to one and one-half hours after packaging.
Processing shortly after packaging fixes the browning agents at or
near the surface of the foodstuff, and foodstuff browning is not
diminished because of browning agent migration deeper into the
foodstuff.
[0070] Alternatively, the food product can be subjected to a
preheating step to transfer the components of the composition to
the foodstuff and fix the color prior to cooking. For example, the
packaged foodstuff can be preheated to a temperature of about
150.degree. F. to about 200.degree. F. for a period of up to about
6 minutes. During cooking or preheating, the browning agent of the
present composition imparts an esthetic color to the surface of the
food.
EXAMPLE 1
Coating Compositions
[0071] Coating compositions of the present invention were prepared
according to Table 1 by admixing composition components.
1TABLE 1 Composition Meat and Cooking No. Composition (wt %)
Variables C.sub.3/02 MAILLOSE .RTM. 45.sup.1) 94.63 Uniform surface
Propylene Glygol 5.00 color. No purge. Dioctyl Sulfosuccinate 0.25
.DELTA.L = 7.7 Xanthan Gum 0.12 C.sub.1 MAILLOSE .RTM. 45.sup.1)
94.50 Uniform surface Propylene Glygol 5.00 color. No purge.
Dioctyl Sulfosuccinate 0.25 .DELTA.L = 9.9 Xanthan Gum 0.25 C.sub.2
MAILLOSE .RTM. 45.sup.1) 94.50 Purge heavy when Propylene Glygol
5.00 product held Dioctyl Sulfosuccinate 0.25 prior to proces-
Xanthan Gum 0.25 sing. Color splotchy. C.sub.3 WFE.sup.2) 94.00
Purge heavy when Propylene Glycol 5.00 product held Xanthan Gum
0.30 prior to proces- Konjac Gum 0.20 sing. Color METHOCEL .RTM.
E-15 0.50 splotchy. C.sub.x WFE.sup.2) 94.75 Slight purge when
Propylene Glycol 5.00 product held Dioctyl Sulfosuccinate 0.25
prior to proces- sing. .DELTA.L = 7.88 C.sub.4 WFE 94.875 Very
splotchy Propylene Glycol 5.000 color. Xanthan Gum 0.125 C.sub.5
WFE 94.875 Very splotchy Caramel Color 5.000 color. Propylene
Glycol 5.000 Xanthan Gum 0.125 C.sub.6 MAILLOSE .RTM. 45 94.75
Heavy gelatinous Propylene Glycol 5.00 purge. METHOCEL .RTM. SG
A16M 0.25 C.sub.7 MAILLOSE .RTM. 45 94.875 Uniform surface
Propylene Glycol 5.000 color. Dry sur- METHOCEL .RTM. SG A16M 0.125
face. .DELTA.L = 13.9 C.sub.8 WFE 94.75 Heavy gelatinous Propylene
Glycol 5.00 purge. METHOCEL .RTM. A16M 0.25 C.sub.9 WFE 94.875
Uniform color. Propylene Glycol 5.000 Dry surface. METHOCEL .RTM.
SG A16M 0.125 .DELTA.L = 19.1 C.sub.10 WFE 94.94 Uniform color.
Propylene Glycol 5.00 Dry surface. METHOCEL .RTM. SG A16M 0.06
.DELTA.L = 5.65 C.sub.11 R26 RTP.sup.3) 94.875 Uniform color.
Propylene Glycol 5.000 Dry surface. METHOCEL .RTM. SG A16M 0.125
C.sub.12 WFE 84.875 Uniform color. Caramel 10.000 Dry surface.
Propylene Glycol 5.000 Caramel added for METHOCEL .RTM. SG A16M
0.125 staining power to darken. C.sub.13 RA 9751.sup.4) 94.875 Dry
surface. Propylene Glycol 5.000 Very splotchy pH METHOCEL .RTM. SG
A16M 0.125 12.5 liquid smoke for staining/- color develop- ment.
C.sub.14 WFE 97.375 Uniform surface Propylene Glycol 2.500 color.
Dry METHOCEL .RTM. SG A16M 0.125 surface. .DELTA.L = 6.34 C.sub.15
WFE 92.44 Splotchy color. Propylene Glycol 7.50 Surface dry.
METHOCEL .RTM. SG A16M 0.06 C.sub.16 WFE 92.44 Splotchy color.
Glycerol 7.50 Surface dry. METHOCEL .RTM. SG A16M 0.06 C.sub.17 WFE
94.875 Glycerol 5.000 METHOCEL .RTM. SG A7C 0.125 C.sub.18 WFE (42%
HA) 94.875 Dark, dull brown. Propylene Glycol 5.000 Dry surface.
METHOCEL .RTM. SG A16M 0.125 Splotchy. Vis- cosity too high to
uniformly coat. C.sub.19 WFE (47% HA) 94.875 Propylene Glycol 5.000
METHOCEL .RTM. SC A16M 0.125 C.sub.20 MAILLOSE .RTM. 45 98.4
Uniform mahogany Propylene Glycol 1.4 color. Dry METHOCEL .RTM. K
100M 0.2 surface. C.sub.21 WFE 98.4 Uniform mahogany Propylene
Glycol 1.4 color. Dry METHOCEL .RTM. K 100M 0.2 surface. C.sub.22
WFE (42% HA) 100.0 Uniform brown color. Dry sur- face. Casing
splotchy. Vis- cosity too high. C.sub.23 MAILLOSE .RTM. 45 99.75
Xanthan Gum .25 C.sub.24 WFE (70 Brix) 94.8 Propylene Glycol 5.0
METHOCEL .RTM. K 100M 0.2 C.sub.25 WFE (70 Brix) 94.875 Splotchy,
no Propylene Glycol 5.000 purge, .DELTA.L = 12.51 METHOCEL .RTM. SG
A16M 0.125 C.sub.26 MAILLOSE .RTM. 45 97.20 METHOCEL .RTM. K100M
0.35 Propylene Glycol 2.45 C.sub.27 WFE.sup.2) 94.875 Splotchy,
some METHOCEL .RTM. SG A16M 0.125 purge, .DELTA.L = 14.41 Propylene
Glycol 5.0 C.sub.28 WFE.sup.2) 94.814 Uniform color, no METHOCEL
.RTM. SG A16M 0.186 purge, good Propylene Glycol 5.0 casing to meat
adhesion, .DELTA.L = 10.63 C.sub.29 WFE.sup.2) 94.78 Splotchy,
slight METHOCEL .RTM. SG A16M 0.22 purge, .DELTA.L = 13.35
Propylene Glycol 5.0 C.sub.30 WFE.sup.2) 94.875 Very splotchy,
METHOCEL .RTM. K 100M 0.125 excess purge, Propylene Glycol 5.0
.DELTA.L = 14.12 C.sub.31 WFE.sup.2) 94.814 Uniform color, METHOCEL
.RTM. K 100M 0.186 slight purge, Propylene Glycol 5.0 .DELTA.L =
11.76 C.sub.32 WFE.sup.2) 94.78 Very splotchy, METHOCEL .RTM. K
100M 0.22 excess purge, Propylene Glycol 5.0 .DELTA.L = 14.94
C.sub.33 WFE.sup.2) 94.625 Uniform color, METHOCEL .RTM. SG A16M
0.125 slight purge, Dioctyl Sulfosuccinate 0.250 .DELTA.L = 11.23
Propylene Glycol 5.000 C.sub.34 MAILLOSE.sctn. 45 94.875 Slightly
Propylene Glycol 5.000 splotchy, good METHOCEL .RTM. SG A16M 0.125
casing to meat adhesion, .DELTA.L = 17.01 C.sub.35 WFE.sup.2)
92.875 Very splotchy, Propylene Glycol 5.000 purge moderate, Sodium
Chloride 2.000 .DELTA.L = 11.06 METHOCEL .RTM. SG A16M 0.125
C.sub.36 WFE.sup.2) 94.75 Difficult to Propylene Glycol 5.00 shirr.
Slightly Dioctyl Sulfosuccinate 0.25 splotchy, no purge. AL = 11.41
C.sub.37 WFE (pH 5.5).sup.2) 94.875 Splotchy surface, Propylene
Glycol 5.000 no purge, METHOCEL .RTM. SG A16M 0.125 .DELTA.L =
12.37 C.sub.38 WFE (70 Brix) 94.625 Propylene Glycol 5.000 Dioctyl
Sulfosuccinate 0.250 METHOCEL .RTM. SG A16M 0.125 C.sub.39 MAILLOSE
.RTM. 45 94.625 Propylene Glycol 5.000 Dioctyl Sulfosuccinate 0.25
METHOCEL .RTM. SG A16M 0.125 .sup.1)MAILLOSE .RTM. 45 contains 27
wt % hydroxyacetaldehyde, and is available from Red Arrow Products
Co. LLC, Manitowoc, WI; .sup.2)WFE contains 35.4 wt %
hydroxyacetaldehyde (HA) and is available from Red Arrow Products
Co. LLC, Manitowoc, WI; .sup.3)R26 RTP contains 8.7 wt %
hydroxyacetaldehyde and is available from Red Arrow Products Co.
LLC, Manitowoc, WI; and .sup.4)RA 9751 is free of
hydroxyacetaldehyde and primarily is a stain for foods (pH 12.7),
available from Red Arrow Products Co. LLC, Manitowoc, WI.
[0072] A preferred composition contains about 90 to 97 wt % WFE or
MAILLOSE.RTM. (65 brix) for maximum browning and optimum solids,
about 5 wt % propylene glycol for METHOCEL.RTM. hydration and ease
of peeling, about 0.125 wt % SG A16M METHOCEL.RTM. for water
binding, viscosity control, and surface tension control, about 2 wt
% sodium chloride to normalize the composition with meat-free water
and thereby minimize composition/color migration and to reduce
METHOCEL gel temp, and pH 5 by the addition of a sufficient amount
of sodium hydroxide (NaOH) or phosphate to minimize protein
syneresis and purge.
EXAMPLE 2
Corona Treatment of a Polyamide Film
[0073] The following tests were performed on a three-layer
heat-shrinkable tubular film having an outer polyamide layer, an
intermediate polypropylene copolymer layer, and an inner polyamide
layer. The inner layers were subjected to a pretreatment to provide
an irregular surface morphology.
[0074] The tubular film was internally corona treated at 600 watt
13.6 kilovolt using an electrode apparatus similar to that
described in U.S. Pat. No. 5,296,170, wherein one of a pair of
electrodes is placed in contact with one side of an inflated tube.
In this way, a corona discharge is generated in the air space
within the tube. However, a significant difference between the
method described in U.S. Pat. No. 5,296,170 is that in the present
example, much higher power levels are used. Although U.S. Pat. No.
5,296,170 does not disclose the power level in watt density, the
examples show an increase in dyne level of a polyethylene film from
31 dyne to 42 and 41 dyne. However, it can be estimated from this
change in dyne level that the power level is about 18 and 23 watt.
In order to provide for the significant increase in power level for
the present process, two electrode treater stations were mounted in
series. The total power was split equally between the two
stations.
[0075] After corona treatment, the interior surface of the film was
coated by slugging as described in U.S. Pat. No. 3,378,379 and
summarized below:
[0076] 1. The tube is slit open and an amount or "slug" of the
coating is added;
[0077] 2. Air is injected to form the tube into a cylindrical shape
and the slit is sealed with a tape;
[0078] 3. The tube is advanced through, and partially collapsed
through, a set of coating rolls. The spacing between the coating
rolls is adjustable such that the rolls are not totally closed. As
the film with the coating passes through the rolls; most of the
liquid is squeezed out; and
[0079] 4. The film with the coating on the inside surface is then
wound into reels.
[0080] Three coating trials were conducted with varying levels of
corona treatment followed by coating under identical conditions of
speed, nip roll gap, and nip roll structure. The level of surface
activation was estimated by measuring the surface energy in dynes.
The results are summarized in Table 2. The composition used was
Composition No. C.sub.1, the components of which are set forth in
Table 1.
2TABLE 2 Line Corona Dyne Speed Add-on.sup.1) Treatment Level
W-min/cm.sup.2 (fpm) mg/cm.sup.2 Increase % No 52 0 45 0.40 0 Yes
58 78 45 0.46 15 Yes 66-70 228 45 0.67 67.5 .sup.1)The amount of
coating composition retained was measured by weighing the film
before and after coating.
[0081] The results summarized in Table 2 show a 67% increase in the
amount of composition that can be absorbed into the inner layer of
the casing, and the amount of coating composition retained on the
inner surface of the film directly correlates to the level of
corona treatment, as measured in dynes.
[0082] The dyne levels in Table 2 are well in excess of that
achieved by corona treatment used to facilitate meat adhesion,
i.e., between 40 to 50 dynes provide acceptable meat adhesion. It
is generally accepted in the art: that if films are treated to a
dyne level above about 50 dynes, then the film unduly adheres to
the meat surface. In the present invention, it was surprisingly
observed that despite these high levels of surface activation, the
composition-treated film unexpectedly released cleanly from the
meat surface without meat scarring.
[0083] In the experiments it was observed that the surface
activation was sufficiently high such that the dyne level was
outside of the usual dyne measurement techniques. For this reason,
the level of surface activation was estimated in terms of watt
density.
[0084] Watt density is calculated according to the following
formula: 1 Watt density = power supple ( watts ) tube width ( M )
.times. 2 .times. line speed ( min / M )
[0085] The width of tube was multiplied by two to account for the
fact that the tube is double sided. Such a correction would not be
necessary for a single sheet film.
[0086] To further demonstrate the amount of composition that can be
absorbed into a polyamide film is a function of the corona
treatment, the film used in the tests of Table 1 was treated at two
different corona levels. Moisture then was applied to the film and
the amount of moisture absorbed was determined per ASTM 570. This
test requires specimens to be conditioned in an oven for 24 hours
at 50.degree. C. cooled in a desiccator, then immediately weighed
to the nearest 0.001 g. After conditioning, the test specimens were
immersed in distilled water that was maintained at room temperature
(23.degree. C..+-.1C.degree.) for 72 hours. At the end of the test,
the specimens were removed from the water, all surface water was
wiped off with a dry cloth, then the specimen was weighed
immediately to the nearest 0.0001 g.
[0087] To calculate the percentage increase in weight during
immersion, the following equation was used: 2 Increase in weight ,
% = ( Wet weight - Initial weight ) Initial weight .times. 100
[0088] Table 3 summarizes the results of the test. The results
indicate that the amount of moisture that is absorbed increases as
the corona level is increased.
3 TABLE 3 Test % Weight Gain W-m/M.sup.2 1 no corona 12.9 -- 2 14.7
About 75 3.sup.1) 18.7 189.3 .sup.1)For test 3, the inner surface
was further treated to the level indicated. It is estimated that
the dyne level is 70 or higher at the watt density indicated, but
at these levels the dyne test cannot be used with any
reliability.
[0089] To demonstrate that a present composition is absorbed when
applied to the inner surface of the film, the following test was
devised:
[0090] Film samples were cut to fit circular hoops similar to those
used to hold cloth when doing needle point. The inner surface of
the film was placed in the hoop so that the rim of the hoop and the
film formed a container. Before the film was clamped into the hoop
the thickness of each film specimen was measured to the nearest
0.0001 in using a linear gauge. All test specimens were conditioned
in an oven for 24 hours at 50.degree. C. and cooled in a
desiccator. The film specimens then were clamped into the
hoops.
[0091] A solution containing MAILLOSE.RTM. (C20) was added to the
inner surface of a film of the structure polyamide/tie/polyamide.
This film is referred to here after as V9. The MAILLOSE.RTM.
solution was added to just cover the surface of the film. This
method insures that only the inner surface of the film has solution
applied, and closely simulates the slugging process.
[0092] Excess MAILLOSE.RTM. solution was poured from the hoop, the
specimens were removed from the hoop, then all surface solution was
wiped off with a dry cloth. The specimen was cut into 3 pieces,
then weighed immediately to the nearest 0.0001 g. All film
specimens were then reconditioned for the same time and temperature
as used in the original drying period (24 hours at 50.degree. C.)
and weighed to the nearest 0.0001 g.
[0093] Table 4 summarizes the results obtained for this test. It
can be seen that the amount of composition add-on increased with an
increase corona treatment. These results show that the corona
treatment, as measured in watts per minute per m.sup.2,
considerably increases the level of coating composition that can be
applied to the film.
4 TABLE 4 Treatment Material w-min/m.sup.2 Absorption % V9-control
0 23.9 V9-50 50 28.6 V9-100 100 30.4 V9-150 150 37.0 V9-200 200
33.1 V9-250 250 32.2 V9-300 300 30.6 V9-400 400 30.1 V9-500 500
31.4
EXAMPLE 3
Shirring, Stuffing, and Processing
[0094] Films were coated with the above coatings as described in
Example 2. The coated films, after allowing time for the coating to
adhere and/or be absorbed onto the rolls, were shirred into
"sticks." Shirred tubular casings are prepared by conventional
shirring machines known in the art. Ham or turkey meat products
then are pushed through a stuffing horn into the shirred
casings.
[0095] The encased food products then were cooked in an oven for a
sufficient time for the food product to reach an internal
temperature of 160.degree. F. The oven was maintained at 100%
relative humidity and a temperature of 185.degree. F. Cooking was
conducted as soon as practicable after stuffing. Controls were
conducted in the absence of corona treatment and coating.
[0096] The results are summarized in Table 5.
5TABLE 5 Inner Coating Treatment Add-on Product Colorimetric Values
Layer Type Colorant W-min/m.sup.2 mg/cm.sup.2 Type L a b .DELTA.L
LLDPE None None None None Turkey 71.43 5.70 8.80 -- Nylon C.sub.9
Liquid 205.8 .94 Turkey 56.55 11.47 22.40 14.88 Smoke LLDPE None
None None None Ham 65.35 12.02 9.72 -- Nylon C.sub.9 Liquid 169.8
.90-1.00 Ham 50.36 14.91 23.70 14.99 Smoke LLDPE None None None
None Ham 65.69 11.86 5.59 -- Nylon C MAILLOSE .RTM. 196 .42 Ham
62.45 11.86 19.84 3.24 Nylon C.sub.6 MAILLOSE .RTM. 61.2 .56 Ham
59.01 12.90 21.26 6.68 LLDPE None None None None Turkey 74.14 5.19
8.32 -- Nylon C MAILLOSE .RTM. 196 .42 Turkey 69.49 9.78 27.35 4.65
Nylon C.sub.6 MAILLOSE .RTM. 61.2 .56 Turkey 62.40 10.93 27.02
11.74 LLDPE None None None None Turkey 75.1 N/A N/A -- LLDPE C
MAILLOSE .RTM. 300 .42 Turkey 73.4 N/A N/A 1.7 Nylon C MAILLOSE
.RTM. 300 .42 Turkey 67.4 N/A N/A 7.7 L value - The lower the
number, the greater the color density a value - The higher the
number, the more intense a red hue b value - The higher the number,
the more intense a yellow hue LLDPE--Linear low density
polyethylene
[0097] Both the ham and turkey products cooked in the treated film
have a uniform, smoked brown color. The uniform color of the
foodstuff indicates that a composition of the present invention is
uniformly coated on the film, and that this uniform coating is
resistant to disruption by shirring and stuffing procedures. A
composition of the present invention also has sufficient
flexibility to stretch during stuffing and shrink during
heat-shrinkage of the film. Still further, there is no evidence of
purge or cook-out, or an unacceptable adhesion of the film to the
foodstuff.
[0098] Accordingly, a surface treated film can retain a composition
of the present invention in a significantly greater amount than an
untreated film. Further, a surface treated film can be shirred and
stuffed by conventional shirring and stuffing procedures.
EXAMPLE 4
[0099] Tests were performed to demonstrate that a composition of
the present invention, after application to a corona-treated
casing, retards migration of the browning composition into an
encased foodstuff. In particular, compositions C.sub.25 through
C.sub.37, and a control, individually, were applied to a
corona-treated casing. Then, the casing was stuffed with chunked
and formed ham using a Tipper RS4202 apparatus. The resulting
foodstuffs were metal molded and hot water cooked at 165.degree. F.
The results in Table 6 illustrate that a present composition
remains at or in the vicinity of the surface of a cooked foodstuff,
thereby maximizing the brown color of the foodstuff surface.
6 TABLE 6 Composition Penetration (mm) C.sub.25 2 C.sub.27 2
C.sub.28 1.5 C.sub.31 1.5 C.sub.34 1.5 C.sub.35 1 C.sub.36 2
C.sub.37 2-3
EXAMPLE 5
[0100] Tests also were performed to demonstrate that cooking
immediately after stuffing provides a deeper, more esthetic golden
brown color. A foodstuff was encased in a corona discharge treated
casing as set forth below. The treated casing had a composition of
the present invention applied thereto.
[0101] The encased food products were cooked by heating in an oven,
with steam or hot water, set for a length of time for the product
to reach an internal temperature of 160.degree. F. The oven was
maintained at 100% relative humidity and a temperature of
185.degree. F. The steam and hot water temperatures are noted in
the following table. Cooking was conducted either as soon as
practicable or at various times after stuffing as noted.
7 Inner Colorimetric Foodstuff Coating Layer L Value Comments
Turkey None LLDPE 74.6 Product held (Control) before processing
Turkey C.sub.3/02 Nylon 72.93 Processed after stuffing Turkey
C.sub.3/02 LLDPE 73.97 Held 4.5 hours Turkey C Nylon 70.07
Processed immediately Turkey C Nylon 73.56 Held 4 hours Turkey
C.sub.1 Nylon 67.55 Processed immediately Turkey C.sub.1 Nylon
73.26 Held 4 hours Turkey C.sub.x Nylon 69.55 Processed immediately
Turkey C.sub.x Nylon 73.75 Held 4 hours Turkey C.sub.2 Nylon 66.33
Processed immediately Turkey C.sub.2 Nylon 61.48 Held 4 hours
Turkey C.sub.3 Nylon 66.57 Processed immediately Turkey C.sub.3
Nylon 66.27 Held 4 hours Turkey C.sub.1 Nylon 67.55 Processed
immediately Turkey C.sub.1 Nylon 73.26 Held 4 hours Turkey C.sub.1
Nylon 61.67 Processed immediately Turkey C.sub.1 Nylon 64.51 Held 4
hours
[0102] It will be appreciated that various changes and
modifications may be made to the invention described herein without
departing from the spirit and scope thereof.
* * * * *