Note: Descriptions are shown in the official language in which they were submitted.
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~PECIFICATI(~N_
TITLE
"GUM BASE AND CHEWING GUiM CONTAINING
EDIBLE POLYESTERS"
S
RELATED APPLICATJfONS
This is a continuation-in-part of PCT patent application PCT/LJS97/18885,
filed on October 20, 1997, which is a continuation-in-part of PCT patent
application
PCT/LJS96/16986, filed on October 22, 1996.
' BACKGROUND OF THE INVENTION
The present invention relates generally to~ chewing gum. More specifically
the present invention relates to improved formulations, for chewing gum and
gum bases.
It is of course known to construct chewing gum from a water insoluble gum
base and a water soluble portion along with flavor~(s). Gum base is designed
to be
retained in the mouth throughout the chewing period. The water soluble portion
and
flavors are designed to dissipate during chewing.
Insoluble gum base generally comprises elastomers, resins, fats and oils,
softeners, and inorganic fillers. The eiastomers can include either synthetic
elastomers
or natural eiastomers. Natural elastomers include nairural rubber. Synthetic
elastomers
include polyisobutylene, isobutylene-isoprene copolymers, styrene-butadiene
copolymers, polyvinyl acetate, polyisoprene, polyethylene, vinyl acetate -
vinyl laurate
copolymers, and combinations thereof.
It is also known to use in gum base elastomer plasticizers. Such elastomer
plasticizers can include natural rosin esters as well as other elastomer
plasticizers.
Additionally, chewing gum base can include filler/te;xturizers and
softenerlemulsifiers.
Softeners optimize the chewabiiity and mouth feel of the chewing gum.
Softener/emulsifiers that are typically used include tallow, hydrogenated
tallow,
hydrogenated and partially hydrogenated vegetable oils, cocoa butter, glycerol
monostearate, glycerol triacetate, lecithin, and combinations thereof.
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In addition to a water insoluble gum base portion, a typical chewing gum
composition includes a water soluble portion and one or more flavoring agents.
The
water soluble portion can include bulk sweeteners, Thigh intensity sweeteners,
flavoring
agents, softeners, emulsifiers, colors, acidulants, fillers, antioxidants, and
other
components that provide desirable attributes.
SUMMARY OF THE IN~JEI~.T_IOl~
The present invention provides improved chewing gum formulations and
bases, as well as methods of producing chewing gum and bases. Pursuant to the
present
invention chewing gum and gum bases that include end-capped edible polyesters
are
provided. In this regard, traditionally used elastomers and elastomer
plasticizers can be
replaced with these edible polyesters.
To this end the present invention provides, in an embodiment, a gum base
including at least one edible polyester that is produc<;d through a reaction
of at least one
alcohol chosen from the group consisting of glyceroJ~, propylene glycol, and
I,3 butylene
diol, and at least one acid chosen from the group consisting of fumaric acid,
adipic acid,
malic acid, succinic acid, and tartaric acid. The polyester is then end-capped
with a
monofunctional ingredient selected from the group consisting of alcohols,
acids,
chlorides and esters.
In an embodiment, the monofunctional ingredient is chosen from the group
consisting of long chain or medium chain acyl alcohols, acyl chlorides, fatty
acids, fatty
alcohols and fatty acid esters.
In an embodiment, the base is wax-free..
In an embodiment, the base is non-tacky.
In an embodiment, the base is a bubble gum-type base.
In an embodiment, the edible polyester comprises approximately 1 % to about
80% by weight of the base.
In another embodiment, the present inv<;ntion provides a gum base including
at least approximately 1% by weight of an edit~le polyester that is a product
of a
condensation reaction of at least one alcohol chosen from the group consisting
of
trihydroxyl alcohol and dihydroxyl alcohol, and at least one acid chosen from
the group
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consisting of dicarboxylic acid and tricarboxylic acid. The polyester is then
end-capped
with a monofunctional ingredient selected from the group consisting of
alcohols, acids,
chlorides and esters.
In an embodiment, the monofunctional ingredient is chosen from the group
consisting of long or medium chain acyl alcohols, acyl chlorides, fatty acids,
fatty
alcohols, and fatty acid esters.
In a further embodiment, the present invention provides a chewing gum
formulation comprising an insoluble gum base, a water soluble portion, a
flavor, and at
least 0.1% by weight of an edible polyester. The edible polyester is produced
by the
reaction of at least one alcohol chosen from the group consisting of glycerol,
propylene
glycol, and 1,3 butylene dioi and at least one acid chosen from the group
consisting of
citric acid, fumaric acid, adipic acid, malic acid, suc;cinic acid, and
tartaric acid. The
polyester is then end-capped with a rnonofunctional ingredient selected from
the group
consisting of alcohols, acids, chlorides, and esters.
In an embodiment, the formulation includes a bulk sweetener.
In an embodiment, the formulation includes a high intensity sweetener.
In an embodiment, the formulation includes an elastomer plasticizer.
In an embodiment, the formulation includes an elastomer.
In an embodiment, the chewing gum is sugar free.
In yet a still further embodiment, the present invention a method for
manufacturing chewing gum comprising the step of adding to a water soluble
portion and
a flavor an edible polyester that is produced by the condensation reaction of
at least one
alcohol chosen from the group consisting of trihydro~;yl alcohol and
dihydroxyl alcohol
and at least one acid chosen from the group consisting of dicarboxylic acid
and
tricarboxylic acid. The polyester is then end-cappedi with a monofunctional
ingredient
selected from the group consisting of alcohols, acids., chlorides, and esters.
It is an advantage of the present invention to provide an improved gum base.
Still further an advantage of the present invention is to provide an improved
chewing gum formulation.
Another advantage of the present invention is to provide an improved method
for making chewing gum.
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Still further an advantage of the present invention is to provide an improved
method for making gum base.
Moreover, an advantage of the present invention is that the gum base is
biodegradable.
Furthermore, an advantage of the present invention is to replace traditional
elastorners or eiastomer plasticizers in chewing gum lbases with other
polymers.
Additional features and advantages of the present invention are described in,
and will be apparent from, the detailed description of the presently preferred
embodiments.
DETAILED DESCRIPTION
~F THE PRESENTLY PREFERRED EMBODIMENTS
The present invention provides improved clhewing gum formulations and gum
-- ~ IS' °basewforanulations: - To-this end, the present invention
allows for the replacement or
substitution for traditional elastomers and elastomer plasticizers with other
polymers
specifically edible polyesters that are end-capped.
Polyesters are polymers obtained by the ~esterification of dicarboxylic acid
and dihydroxyl alcohol. Ester linkages may be formed at each end of each
molecule.
Thus, it is possible to build up a large molecule containing many ester
linkages.
For example, one of the most common polyesters in use is polyethylene
terephthalate made from ethylene glycol and terephthalic acid. Polyethylene
terephthalate was developed as a fiber called Dacron. This polyester can also
be used to
make a film having unusual strength. Polyethylene terephthalate is currently
used to
make PET (polyethylene terephthalate) plastic bottles used for soft drinks.
In making polyesters, if a trihydroxyl alcohol such as glycerol is used,
possible crosslinking occurs. The resultant resinous. materials, glyptols,
from glycerol
and phthalic acid, find applications as coatings in thus lacquer and paint
industry.
It is possible to construct polyesters firm edible or food grade materials. To
this end, the tri or dihydroxyl alcohols glycerol, propylene glycol, and 1,3-
butylene diol
can be reacted with tri- or dicarboxylic acids such as citric, fumaric,
adipic, malic,
succinic, and tartaric acids.
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With respect to these alcohols and acids, the reaction of the alcohol and acid
form the ester linkages. As the reaction continues exaended polyester chains
are created
by a condensation reaction. An initial study of various polyesters from these
materials
by the condensation reaction yielded polyesters that had rubbery, plastic or
hard, resin-
s like textures. Because the starting alcohols and .acids are food grade
materials the
resultant product is edible and can be used in food or confectionary products.
Edible polyesters made from glycerol a.nd food grade acids are long chain
polymers that continue to grow by a condensation. reaction and when the
reaction is
stopped, free acid and alcohol ends of the polymer are available. The free
acid and
alcohol ends can be "end-capped" by reacting them with mono-alcohol or mono-
acid
functional ingredients. Examples of materials that can endcap an edible
polyester are:
cetyl alcohol (n-hexadecanol; also called palmitic a.lcohol); palmitic acid;
stearic acid;
stearic alcohol; stearoyl chloride; other medium and long chain fatty alcohols
and acids;
cinnamic aldehyde; cellulose; cellulose acetate;~modi.fied starch; starch;
~adipoyl chloride;
succinic anhydride; glutaric anhydride and other alphatic chlorides and
anhydrides; gum
talha; zein; and gelatin.
In a preferred embodiment, medium and long chain fatty acids are used to
endcap the edible polyester. In a most preferred erntrodiment, palmitic acid
and pahnitic
alcohol are used.
To end-cap an edible polyester, generally about 1% to 35% of fatty
acids/alcohols is used to obtain the desirable polyest<;r. High levels of
fatty acid/alcohols
would afford improved texture, more hydrophobicity, and less water
extractables. A
level of approximately 20 to 28% fatty acid/alcohols is preferred, and most
preferably 22
to 28%, to provide the desired edible polyester. Although higher levels may be
used to
end-cap the polyester, however, too high a level ma:y reduce polyester
biodegradability.
The end-capping material may be added any time dcuing the early, middle, or
late stages
of the reaction.
The end-capped edible polyesters have improved physical properties as base
ingredients replacing elastomers, elastomer plastic;izers, and resins. These
polyesters
have improved texture with more rubberiness, :improved processability,
improved
hydrophobicity for extended flavor retention, and better water extractability.
By end-
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capping the edible polyester, the physical properties are improved making them
more
similar to gum base elastomers, elastomer plasticizers, and resins.
By way of example and not limitation, several polyesters were made using
the various food acids and glycerol or propylene glycol. Gram quantities were
made in
a test tube heated in an oil bath at about I$0°-250°~C from %2
hr. to 5 hours to obtain
polyesters.
The following polyesters were made:
Molar Ratios
Glvcer'~ Propylene Glvcol
A Adipic Acid 2\l.:!8 -
g Adipic Acid 3.54\1.66-
C Adipic Acid 1.412..03-
Malic Acid 2.0\1,.28-
E Malic Acid - 21I
F Malic Acid 2\0.5
G AdipiclMalic Acid 1\1\1.28 -
H Adipic/Malic Acid - 1.511.5\l
1 Adipic Acid - 2\1
Adipic Acid -
K Tarkaric Acid 2\1!,
L Fumaric Acid/Citric - 1\l\1
Acid
M Fumaric Acid 2lll
N Fumaric AcidJCitric I\1\1 -
Acid
p Adipic Acid 2\1\l.**
P Adipic Acid - 21.1 *\2
Q Adipic Acid - 2\.2511
R Adipic Acid - 2\0.4*\2
* Low levels of Glycerol added
** Made with Adipic Acid\Glycerin\Propylene Glycol
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Products that were formed were viscous liquids to waxy rubbery-like or
plastic gels to hard gels. General3y, as the mixtures vwere heated, moisture
was driven off.
Over several hours, liquids turned to gels or if removed from heat became
solid gels.
The resultant polyesters were soft to hard plastic and soft to hard rubbery
characteristics that had resin like texture. These polyesters appear to be
very useful in
a gum product. The glycerol adipate polyester was insoluble in water,
chloroform,
methanol, isopropyl alcohol, 0.1N sodium hydroxide, and concentrated ICI.
Other
polyesters were not tested for solubility but are believed to be less than 1%
soluble in
water.
The compatibility of polyesters with other gum base ingredients can be
improved by increasing the lipophilicity of the polyf~ster. This can be
accomplished by
increasing the length of the carbon backbone between the two acids of the
dicarboxylic
acid molecule.
In this regard, adipic acid has a 4 carbon chain between the two carboxylic
acid groups. By increasing the carbon chain between the two groups to a 6, 8,
or 10
carbon chain, lipophilicity can be increased. The 6 carbon chain diacid is
suberic acid,
and 8 carbon chain diacid is sebacic acid, and the 10 carbon chain diacid is
dodecanedioic acid.
Other types of naturally occurring diacid~s may also be used to provide a more
lipophilic polyester. Some such diacids include g:lucaric acid, glutamic acid;
glutaric
acid, and azelaic acid. Other materials that have at least two carboxylic
acids or alcohol
groups can also be used as reactants. Such materials with alcohol or hydroxyl
groups are
sorbitol, mannitol, glycerol monofariy acids and hydrocolloids.
Polyesters can be made by a variety of processes. Besides conventional
methods of production, polyesters can be made by a condensation reaction in an
extruder,
by a condensation reaction in a batch process, or may be made by an enzymatic
processes. The process of making the polyester is not limiting.
The polyesters that can be used pursuant to the present invention are not
limited to linear polyesters, but can also include polyesters that may be
branched or
crosslinked. These may be made with tricarboxylic acids or trihyrdoxyl
alcohols. The
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desired polyester may have a broad range of physical properties from thick and
syrupy
to hard and rubbery with thermoplastic properties.
The examples of polyesters set forth below in Examples A-E were prepared
from adipic acid and glycerin or propylene glycol. )Both glycerin and
propylene glycol
were predried by heating in a round bottom flask at. 50-60°C under
vacuum overnight
and stored over a dry helium atmosphere. By way of example, and not
limitation, the
following examples were made:
Example A:
In a 2L cylindrical glass reactor equipped with a mechanical stirrer and
heating jacket, 8008 of dried glycerol was charged. A stream of dry helium was
circulated in the reactor and the outlet was connected to a trap maintained in
ice-water.
The solution was heated to 100°C for 90 min. Then 19008 of adipic
was
charged into the reactor and the temperature was raised to 150°C. Water
droplets started
condensing. The amount of water condensed is tabulated below as a function of
reaction
time.
Time of ReactionAmount of water condensedExtent of reaction
completed
90 min 1008 21
150 min 2008 42%
180 min 2508 53%
220 min 3108 66%
240 min 3408 72.6%
After 4 hrs the gel point was reached. Tvc~o samples were picked oazt from the
reactor at 180 min (Sample #A) and 220 min of reactiion (Sample #AA) for
analysis. The
final product (Sample AAA) was recovered from the reactor. It was observed
that the
product near the walls was more sticky than the product inside the reactor and
was kept
in a separate jar. The product inside the reactor was foamy.
FTIR spectroscopy analysis of polymer films of samples A and AA cast an
KBr windows from chloroform solutions confirmed the polycondensation products.
Also
the amount of water condensed from the reaction indicated polyester formation.
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Example B
In a 3L cylindrical glass reactor equipped. with a mechanical stirrer and
heating jacket, 700g {9.19 mole) of dried propylene glycol was charged. A
stream of dry
helium was circulated in the reactor and the outlet was connected to a trap
maintained in
ice cold water.
The solution was heated to 100°C for 90 ~;nin. Then 1344.58 (9.19
mole) of
adipic acid was charged into the reactor and the temperature wasraised to
150°C. Water
droplets started condensing. After two hours the reaction temperature was
raised to
180°C. In about 3 hrs. 210 ml of water was collected in the trap. The
temperature of the
reactor was maintained at 180°C and vacuum was applied for about 2 hrs.
An additional
120 ml of water was collected in the trap.
An SEC (Size Exclusion Chromatography) analysis (Sample B) of the
product indicates the presence of dimers and trimer:>. The total Mw (Weight
Average
Molecular Weight) of the product was found to be 28t)0 and (Weight Average
Molecular
WeightlNumber Average Molecular Weight = Polydlispersity) Mw/Mn =1.75.
The mechanical stirrer was removed from the reactor and the solution was
heated further under vacuum ( 10''mm Hg) at 150 ° C Ibr 2 hrs; at 180
° C for 2 hrs; and at
200°C for another 5 hrs. A 1 S ml quantity of condensate was collected
during this period
of heating under a vacuum. An SEC analysis of this product (Sample #BB) shows
a Mw
of 5500 with Mw/Mn = 1.90.
Example C
In a 3L cylindrical glass reactor equipped with a mechanical stirrer and
heating jacket, 7008 (9.19 mole) of dried propylene glycol was charged. A
stream of dry
helium was circulated in the reactor and the outlet was connected to a trap
maintained in
ice cold waters.
The solution was heated to 70°C for 30 min. Then 1344.58 (9.19
mole) of
adipic acid was charged into the reactor and the temperature was raised to
100°C. Water
droplets started condensing. After one hour 5m1 o:f HCl (0.5 mole%) was added
as a
catalyst and the reaction temperature was raised to 150°C. In about 1
hr. 100 mI of water
was collected in the trap. The pH ofthe collected water was around 4. The
temperature
of the reactor was raised to 180°C and around 145 m.l of water was
callected in the trap.
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An SEC analysis (Sample C) indicates the presence of dimers and trimers.
The total Mw of the product was 1700 and Mw/Mn -= 2:43.
The mechanical stirrer was iemoved from, the reactor. 2.5 ml {0.25 mole%)
of HCl was added and the solution was heated further under vacuum (10-3mm Hg)
at
220°C for 4 hrs. A 25 ml quantity of condensate v~ras collected during
this period of
heating under vacuum. An SEC analysis of this product (Sample #CC) shows the
Mw
to be 3700 with Mw/Mn = 2.47.
As in Example B, size exclusion chromatography (SEC) was carried out on
a Varian liquid chromatograph equipped with a refractive detector. Three GPC
columns
from Supelco were used with THF as the eluent. 7f'lhe columns were calibrated
with
monodisperse polystyrene standards. The molecular weights and the
polydispersity
indice were calculated.
Example D
In a 3L cylindrical glass reactor equipped with a mechanical stirrer and
heating jacket, 3I3 g (4.1 i mole) of dried propylene glycol and 252 g (2.74
mole) of
glycerol were charged. A stream of dry helium was circulated in the reactor
and the
outlet was connected to a trap maintained in ice cold water.
The solution was heated to 75 °C for an Jnour. Then 1200 g (8.22
mole) of
adipic acid was charged into the reactor and the temperature of the reactor
was kept at
75 ° C for 2 hours. The temperature was raised to 180 ° C and
water droplets started
condensing. After 2 hours, 140 ml of water was collected in the trap. The
temperature
of the reactor was increased to 220 ° C and around 90 rnl of water was
collected in another
2 hrs. Vacuum was applied for about 1 hr at 220°C.
The solution became viscous and turned into a gel in about 1 hr. An
additional 30 ml of water was collected in the trap. The final product (Sample
D) was
soft, sticky and difficult to remove from the reactor.
In a 3L cylindrical glass reactor equipped with a mechanical stirrer and
heating jacket, 468 g (6.15 mole) of dried propylene glycol and 252 g (2.74
mole) of
glycerol were charged. A stream of dry helium w;~s circulated in the reactor
and the
outlet was connected to a trap maintained in ice coil water.
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The solution was heated to 75 °C for an lour. Then 1500 g (10.26
mole) of
adipic acid was charged into the reactor and the teml>erature was kept at
75°C for 2 hrs.
The temperature was raised to 180°C and water droplets started
condensing. After 2 hrs.
140 ml of water was collected in the trap. The temperature of the reactor was
increased
to 220°C and around 100 mI of water was collected in another 2 hrs.
Vacuum was
applied for about 1 hr at 220°C.
The solution became viscous and a sample was collected after 30 min.
(Sample EE). It was fluid-like. The vacuum was applied for another 30 min.
upon which
the solution turned into a gel. An additional 70 rnI of water was collected in
the trap.
The reactor was allowed to cool and final product was recovered. The product
(Sample
E) was soft and sticky.
Samples D, E, EE were cross linked arid would not dissolve in THF and
therefore were not analyzed by SEC.
In order to determine the amount of initial material remaining a water
washing of Example E was done. Using a Brabende;r Plasticorder with a 120m1
Sigma
mixer bowl and blade, 75.8 g of Example E was mixed with 20 ml of deionized
water for
16 minutes. After some swelling another 20 ml of water was added and mixed 16
minutes. Then the water extract was removed and more water added. This was
repeated
5 more times and the extracts analyzed for solids content. A total of 1.7% of
Example
E was extracted indicating very little material remained in the polyester.
Polyester
examples D & E were soaked in deionized water at room temperature for about 1
week.
The polyesters were removed from the water and dried in a vacuum oven
overnight at 45
to 50°C.
By way of example, and not limitarion, examples of end-capped polyesters
will now be given.
P
A reaction mixture of 22.6% palmitic acid, 51.6% adipic acid, and 25.8%
glycerol by weight can be prepared as described above. This mixture consists
of
approximately equimolar amounts of acid and hydroxyl groups.
Briefly the process proceeded using a total mixture of 1600 grams and was
as follows: Add 413 grams of dry glycerol to the reaction vessel and heat to
100°C. Add
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825 grams of adipic acid and 362 grams of palmitic acid to the reaction vessel
and heat
to about 150°C and acid continue heating as water starts condensing and
continues to
condense until the reaction mixture reaches gelation. The batch is considered
gelled
when it begins to climb the agitator shaft.
At the gelation point for the polyester, tests have shown that approximately
70% of its acid and hydroxyl groups have reacted. Tliis leaves about 30% of
the acid and
hydroxyl groups non-reacted. A polymer gel has reached its gelatin point where
it is a
solid matrix and can no longer melt; it can be softened, but cannot melt. For
use in gum
base it is desirable to have a gelled polyester in order to reduce water
extractable
materials.
Exam
A quantity of polyester can be prepared by mixing 15% hexadecanol (also
called cetyl alcohol or palrnitic alcohol), 56.6% a~;,idic acid, and 28.4%
glycerol by
weight and can be prepared as previously described.,
xam H
A quantity of polyester can be prepared by mixing I 1.6% palmitic acid,
l I.0% hexadecanol, 51.6% adipic acid, and 25.8% glycerol by weight: Palrnitic
acid
may be added with adipic acid, and hexadecanol ne~~r the end of the batch.
Process the
same as previously described.
The following gum bases were made from the 2 washed polyesters set forth
above using a Haake Rheocord Rheometer and Sigma mixer.
Base Exam~Ie 1
A 50.0 gram quantity of polyester of Example D was placed in a Haake
Rheocord with a Sigma blade mixer. Added to this vvas 20.0 grams of calcium
carbonate
and blended for I S minutes at 115 °C.
Base Example 2
A 45.0 gram quantity of base of Examl>le 1 above was added to the Haake
Rheocord and blended at 115 °C with 20.0 grams of :medium molecular
weight PVAc for
i 5 min.
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Base Example 3
A 50.2 gram quantity of polyester of Example E was placed in the Haake
Rheocord with the sigma mixer blade. Added to this was 30.0 grams of calcium
carbonate and blended at I I S °C for 20 minutes.
Base Example 4
A 40.8 gram quantity of base of Example 3 was placed in the Haake
Rheocord and blended at 115 °C with I O.G grams of low molecular weight
PVAc for 10
minutes.
Gum Examples 5, 6. and 7
The following gums were made from gases made above in a Brabender
Plasticorder at 37°C.
Ex 5 ~6 Ex
7
Base Examples Ex 1 Ex 2 Ex
4
Base, grams 1 g 18 18
I S Sugar, grams 41 41 41
45Be Corn Syrup, 11 11 11
grams
Peppt. Flavor, grams0.7 0.7 0.7
Total 70.7 70.7 70.7
Gum evaluation showed Example S with polyester and calcium carbonate had
a good initial texture but became very soft and tacky in the late chew
texture. Example
6 had a goad initial texture as well as a good texi:ure character throughout
and was
slightly tacky. Example 7 had a good initial texture, but became slightly soft
and slightly
tacky Late.
The polyesters made here were not readily compatible with other base
ingredients such as elastomers, elastomer plasticize;rs, waxes, and fats. By
using a 2-
monoglyceride as the starting diol instead of glycerin or propylene glycol, it
is believed
that more compatible polyesters can be developed and used with other gum base
ingredients.
It was concluded that a quality chewing; gum base and gum product can be
made from polyesters from adipic acid and glycerol and/or propylene glycol.
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The previous Examples F, G, and H of polyesters were made using the
following procedure:
Procedure
The reactants are added to a 2-liter reaction flask having a heating jacket
and
equipped with a stirrer, a nitrogen inlet, a nitrogenwacuum outlet with a
trap, and a
thermocouple. The reactants are added to the reaction vessel in the desired
molar ratios
of alcohol and acid groups (usually stoichiometrically equivalent).
The reaction vessel is purged with nitrogen and heated to 150°C to
ensure
melting of both reactants. After the reactants are melted, the mixture is
stirred with a
mechanical stirrer. The mixture is allowed to react for 2-3 hours.
Water is then collected in the condenser and measured to determine the extent
of the reaction. When water elution slows (usually about an hour), the
nitrogen purge is
discontinued and the system is run under vacuum. When water elution slowed
again
(about 1 hour), the temperature is raised to 180°C. After the polyester
forms a viscous
1 S gel (about 70% reaction completion) and begins to climb the agitator shaft
that stops the
mixer (usually about 0.5 to 1 hour), the heat is removed. The polyester is
then removed
and allowed to cool.
Pursuant to the present invention, the polyesters can be used in base
formulations and/or chewing gum formulations. In this regard, the polyesters
can be used
as elastomers andlor elastomer plasticizers. As part of a gum base, the edible
polyesters
can comprise approxirnateiy 1 to about 80% by weight of the gum base. As part
of the
chewing gum, the edible polyesters can comprise approximately 0.1 to about 70%
by
weight of the chewing gum.
The polyesters can be used in a variety of different chewing gum and base
formulations.
As previously noted, chewing gum generally consists of a water insoluble
gum base, a water soluble portion, and flavors.
The insoluble gum base generally comprises elastomers, resins, fats and oils,
softeners, and inorganic fillers. The gum base may or may not include wax. The
insoluble gum base can constitute approximately 5 to about 95 percent, by
weight, of the
chewing gum, more commonly, the gum base corn~prises 10 to about 50 percent of
the
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gum, and in some preferred embodiments; 20 to about 35 percent, by weight, of
the
chewing gum.
In an embodiment, the chewing gum base of the present invention contains
about I % to about 80% weight percent food grade polyester, about 20 to about
60 weight
percent synthetic elastomer, 0 to about 30 weight percent natural elastorner,
about 5 to about 55 weight percent elastomer pl~~sticizer, about 4 to about 35
weight
percent filler, about 5 to about 35 weight percent softener, and optional
minor amounts
(about one percent or less) of miscellaneous ingredlients such as colorants,
antioxidants,
etc.
Synthetic elastomers may include, but are not limited to, polyisobutylene with
a GPC weight average molecular weight of about 10,000 to about 95,000,
isobutylene-
isoprene copolymer (butyl elastomer), styrene-butadiene copolymers having
styrene-
butadiene ratios of about 1:3 to about 3:1, polyvinyl acetate having a GPC
weight
average molecular weight of about 2,000 to aboul: 90,000, polyisoprene,
polyethylene,
vinyl acetate-vinyl Iaurate copolymer having vinyl laurate content of about 5
to about 50
percent by weight of the copolymer, and combinations thereof.
Preferred ranges are, for polyisobutylene, 50,000 to 80,000 GPC weight
average molecular weight, for styrene-butadiene, 1:1 to 1:3 bound styrene-
butadiene, for
polyvinyl acetate, 10,000 to 65,000 GPC weight average molecular weight with
the
higher molecular weight polyvinyl acetates typically used in bubble gum base,
and for
vinyl acetate-vinyl laurate, vinyl laurate content of 10-45 percent.
If used, natural elastomers may include natural rubber such as smoked or
liquid latex and guayule as well as natural gums such as jelutong, lechi
caspi, perillo,
sorva, massaranduba balata, massaranduba chocolate, nispero, rosindinha,
chicle, gutta
hang kang, and combinations thereof. The preferred synthetic elastomer and
natural
elastomer concentrations vary depending on whetYier the chewing gum in which
the base
is used is adhesive or conventional, bubble gum. or regular gum, as discussed
below.
Preferred natural elastomers include jelutong, chi.cle, sorva and massaranduba
balata.
If used, elastomer plasticizers may include, but are not limited to, natural
rosin esters, often called estergums, such as glycerol esters of partially
hydrogenated
rosin, glycerol esters polymerized rosin, glycerol esters of partially
dimerized rosin;
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glycerol esters of rosin, pentaerythritol esters of partially hydrogenated
rosin, methyl and
partially hydrogenated methyl esters of rosin, pentaerythritol esters of
rosin; synthetics
such as terpene resins derived from alpha-pinene, beta-pinene, and/or d-
lirnonene; and
any suitable combinations of the foregoing. the prel:erred elastomer
plasticizers will also
vary depending on the specific application, and on the type of elastomer which
is used.
Fillers/texturizers may include magnesium and calcium carbonate, ground
limestone, silicate types such as magnesium and ahxxninum silicate, clay,
aiumina, talc,
titanium oxide, mono-, di- and tri-calcium phosphate, cellulose polymers, such
as wood,
and combinations thereof.
Softenerslemulsifiers may include tallow, hydrogenated tallow, hydrogenated
and partially hydrogenated vegetable oils, cocoa buster, glycerol
monostearate, glycerol
triacetate, lecithin, mono-, di- and triglycerides, acetylated monoglycerides,
fatty acids
(e.g. stearic, palmitic, oleic and linoleic acids), and combinations thereof.
Colorants and whiteners may include FD&C-type dyes and lakes, fn~it and
vegetable extracts, titanium dioxide, and combinations thereof.
The base may or rnay not include wax. .An example of a wax-free gum base
is disclosed in U.S. Patent No. 5,286,500, the disclosure of which is
incorporated herein
by reference.
In addition to a water insoluble gum base portion, a typical chewing gum
composition includes a water soluble bulk portion a~ld one or more flavoring
agents. The
water soluble portion can include bulk sweeteners, high intensity sweeteners,
flavoring
agents, softeners, emulsifiers, colors, acidulanta, fillers, antioxidants, and
other
components that provide desired attributes.
The softeners, which are also known as plasticizers and plasticizing agents,
generally constitute between approximately 0.5 to about 15% by weight of the
chewing
gum. The softeners may include glycerin, lecithin, and combinations thereof.
Aqueous
sweetener solutions such as those containing sorbitol, hydrogenated starch
hydrolysates,
corn syrup and combinations thereof, may also be used as softeners and binding
agents
in chewing gum.
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Bulk sweeteners include both sugar and sugarless components. Bulk
sweeteners typically constitute 5 to about 95% by weight of the chewing gum,
more
typically, 20 to 80% by weight, and more commonly, :30 to 60% by weight of the
gum.
Sugar sweeteners generally include sac:charide-containing components
S commonly known in the chewing gum art, including, but not limited to,
sucrose,
dextrose, maltose, dextrin, dried invert sugar, fructose, galactose, corn
syrup solids, and
the like, alone or in combination.
Sarbitol can be used as a sugarless sweetener. Additionally, sugarless
sweeteners can include, but are not limited to, other sugar alcohols such as
mannitol,
hydrogenated isomoltulase (palatinit), xylital, hydrogenated starch
hydrolysates, maltitol,
lactitol and the like, alone or in combination.
High intensity artificial sweeteners can also be used in combination with the
above. Preferred sweeteners include, but are not limited to sucralose,
aspartame, salts of
acesulfame, alitame, saccharin and its salts, cyclamic acid and its salts,
glycyrrhizin,
dihydrochalcones, thaumatin, monellin, and the Like, .alone or in combination.
In order
to provide longer lasting sweetness and flavor perception, it may be desirable
to
encapsulate or otherwise control the release of at least a portion of the
artificial
sweetener. Such techniques as wet granulation, wax granulation, spray drying,
spray
chilling, fluid bed coating, coacervation, and fiber extension may be used to
achieve the
desired release characteristics.
Usage level of the artificial sweetener will vary greatly and will depend on
such factors as potency of the sweetener, rate of release, desired sweetness
of the product,
level and type of flavor used and cost considerations. Thus, the active level
of artificial
sweetener may vary from 0.02 to about 8%. When carriers used for encapsulation
are
included, the usage level of the encapsulated sweetener will be
proportionately higher.
Combinations of sugar andlor sugarless sweeteners may be used in chewing
gum. Additionally, the softener may also provide additional sweetness such as
with
aqueous sugar or alditol solutions.
If a low calorie gum is desired, a low caloric bulking agent can be used.
Example of low caloric bulking agents include: polydextrase; Raftilose,
Raftilin;
Fructooligosaccharides (NutraFlora); Palatinose oligasaccharide; Guar Gum
Hydrolysate
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(Sun Fiber); or indigestible dextrin (Fibersol). However, other low calorie
bulking agents
can be used.
A variety of flavoring agents can be used. The flavor can be used in amounts
of approximately 0.1 to about 15 weight percent of the gum, and preferably,
about 0.2 to
about 5%. Flavoring agents may include essential c>ils, synthetic flavors or
mixtures
thereof including, but not limited to, oils derived from lalants and fruits
such as citrus oils,
fruit essences, peppermint oil, spearmint oil, other mint oils, clove oil, oil
of wintergreen,
anise and the like. Artificial flavoring agents and components may also be
used. Natural
and artificial flavoring agents may be combined in any sensorially acceptable
fashion.
The present invention, it is believed, can b~e used with a variety of
processes
for manufacturing chewing gum.
Chewing gum is generally manufactured by sequentially adding the various
chewing gum ingredients to commercially available mixers known in the art.
After the
ingredients have been thoroughly mixed, the chewing gum mass is discharged
from the
mixer and shaped into the desired form, such as by rolling into sheets and
cutting into
sticks, extruding into chunks, or casting into pellets.
Generally, the ingredients are mixed by first melting the gum base and adding
it to the running mixer. The gum base may alternatively be melted in the
mixer. Color
and emulsif ers can be added at this time.
A chewing gum softener such as glycerin can be added next along with part
of the bulk portion. Further parts of the bulk portion may then be added to
the mixer.
Flavoring agents are typically added with the final part of the bulk portion.
The entire
mixing process typically takes from five to fifteen minutes, although longer
mixing times
are sometimes required.
it should be understood that various changes and modifications to the
presently preferred embodiments described herein will be apparent to those
skilled in the
art. Such changes and modifications can be made wii.hout departing from the
spirit and
scope of the present invention and without diminishing its attendant
advantages. It is
therefore intended that such changes and modifications be covered by the
appended
claims.
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