Foam inducing compositions and method for manufacture thereof

A full fat and foam inducing composition for use in reduced fat food products is provided. The composition is an aqueous gel matrix of ester vesicles which is provided by a mixture of diacetyl tartaric acid mono fatty acid glyceride ester and a second ester having a hydrophilic-lipophilic balance of above about 10 and a melting point above about 100.degree. F.

FIELD OF THE INVENTION 
The present invention relates generally to aerated food products. More 
particularly, the present invention relates to a foam inducing composition 
which is an aqueous matrix of ester vesicles for use in reduced fat and 
full fat food products. 
BACKGROUND OF THE INVENTION 
Many types of aerated food products are known in the marketplace. Such 
products include ice cream, cream cheese, butter, margarine, yogurt, salad 
dressings, sauces, puddings, gelatin desserts, process cheese spreads dips 
and peanut butter. The amount of aeration in the food product is 
characterized by the term "overrun". Overrun is the relationship of the 
volume of the aerated food product to that of the unaerated food product. 
Overrun is calculated by the following formula: 
##EQU1## 
Thus, an overrun of 100 means that the volume of the aerated food product 
is twice as much as the volume of the unaerated food product. 
It is difficult to provide stable food products that have an overrun above 
200. Such high overrun aerated food products tend to collapse and undergo 
syneresis. High overrun food products also tend to be difficult to freeze 
without undergoing product degradation. 
The present invention is directed to providing an aqueous matrix of ester 
vesicles which can be used to induce an aerated or foam structure in fluid 
food products, wherein the aerated food product is very stable even when 
high overruns of 200 to 1200 are imparted. 
It is a principal object of the present invention to provide a composition 
which can be used in food products to provide an aerated texture. 
It is a further object of the present invention to provide aerated food 
products with high overrun which are stable and do not undergo syneresis 
after extended storage periods. 
SUMMARY OF THE INVENTION 
A foam inducing composition for use in full fat and reduced fat food 
products is provided. The composition is an aqueous gel matrix of ester 
vesicles which is provided by a mixture of a first ester which is diacetyl 
tartaric acid mono fatty acid glyceride ester and a second ester having a 
hydrophilic/lipophilic balance (HLB) above about 10 and a melting point 
above about 100.degree. F. The second ester can be selected from the group 
consisting of mono-, di- and tri-fatty acid esters of sucrose polyglycerol 
fatty acid esters, polyglycerol fatty acid esters, decaglycerol 
monostearate and sodium stearoyl lactylate.

DETAILED DESCRIPTION OF THE INVENTION 
Generally, the present invention is directed to an aqueous composition 
which imparts an aerated foam structure to full fat and reduced fat food 
products. Such food products include pourable dressings, mayonnaise type 
dressings, frozen desserts, whipped topping, cheese and other dairy 
products. The reduced fat food products can have from 0 to about 20% of 
fat. The composition is an aqueous gel matrix of ester vesicles. The ester 
vesicles are provided by a mixture of a first ester which is diacetyl 
tartaric acid mono fatty acid glyceride ester and a second ester having an 
HLB above about 10 and a melting point above about 100.degree. F. In an 
important embodiment of the invention, the second ester is selected from 
the group consisting of mono-, di- and tri-fatty acid esters of sucrose, 
polyglycerol fatty acid esters, decaglycerol monostearate and sodium 
stearoyl lactylate. The preferred sucrose fatty acid is sucrose mono-fatty 
acid ester. 
For technological purposes, it is useful to be able to classify emulsifiers 
according to their stabilizing efficiency for a particular type of 
emulsion. A well established empirical procedure for doing this is the 
hydrophile-lipophile balance (HLB) method of W. C. Griffin, J. Soc. 
Cosmetic Chem., 1, 311 (1949). It is based upon the idea that for a given 
oil and water system, there is an optimum balance between molecular 
hydrophilic and lipophilic character which leads to maximum emulsification 
efficiency. Emulsifiers with low HLB numbers (i.e., in the range of 4-6) 
are suitable for preparing water-in-oil emulsions, while those with high 
HLB numbers (i.e., in the range of 9-18) are suitable for oil-in-water 
emulsions. Emulsifiers with intermediate or medium HLB numbers (6-9) are 
suitable for either type of emulsion depending upon ratio of oil and 
water, temperature and other conditions. 
HLB numbers may be determined experimentally by the method originally 
described by Griffin, or empirically using the formula of J. T. Davies, 
Proc. 2nd Int. Cong. Surface Activity, Vol. 1, p. 426 (1957): 
##EQU2## 
in the above equation, n.sub.H (i) and n.sub.L (j) are empirically-derived 
individual group numbers for the hydrophilic groups (i) and lipophilic 
groups (j) assigned by Davies. 
Using the empirical method, HLB values for specific emulsifiers useful in 
this invention are as follows: Diacetyl tartaric acid monostearate 
glyceride, HLB 8; sucrose monostearate, HLB 16; decaglycerol monostearate, 
HLB 13; sodium stearoyl lactylate, HLB 21. It should be noted that group 
numbers for charged residues depend on the ionic strength of the aqueous 
phase. Therefore, although the calculated HLB value for sodium stearoyl 
lactylate is 21, an experimentally derived HLB value would be closer to 
12. The sucrose esters are mixtures of molecules with various degrees of 
esterification. Although the monoesters have HLB values of 16 or more, as 
more esters are added the molecules become more lipophilic and the HLB 
value decreases. A wide range of HLB values can be obtained from HLB 0 to 
HLB 18 depending on the number and chain length of the esters. The sucrose 
esters most preferred for this invention are those with HLB values greater 
than 10. 
Key considerations for the fatty acid ester substituent of the emulsifier 
components are melting point and crystallization. Typical cis unsaturated 
fatty acids have very low melting points and would therefore be unsuitable 
for this invention. Furthermore, if cis unsaturated fatty acids with very 
low melting points occur in a mixture, they would disrupt the crystal 
packing and destroy the lamellar nature of the complexes needed for this 
invention to work. On the other hand, trans unsaturated fatty acids may 
work very well. They have high melting points and crystallize. 
The preparation of sucrose fatty acid esters useful in the present 
invention is described in U.S. Pat. No. 5,565,557. The preparation of 
polyglycerol fatty acid esters useful in the present invention is 
described in U.S. Pat. No. 3,637,774. 
The fatty acid of the diacetyl tartaric acid mono fatty acid glyceride 
ester is selected from the group consisting of saturated and unsaturated 
C.sub.6 -C.sub.22 fatty acids. Preferred saturated fatty acids are stearic 
acid and palmitic acid. Preferred unsaturated fatty acids are long chain 
(C.sub.16 -C.sub.22) trans unsaturated fatty acids. The fatty acid of the 
sucrose fatty acid and polyglycerol fatty acid esters is also selected 
from the group consisting of saturated and unsaturated C.sub.6 -C.sub.22 
fatty acids. The preferred saturated fatty acids for the sucrose fatty 
acid esters and polyglycerol fatty acid esters are stearic acid and 
palmitic acid. Preferred unsaturated fatty acids are long chain (C.sub.16 
-C.sub.22) trans unsaturated fatty acids. Key considerations in selection 
of fatty acids are the melting point and crystallization of the fatty acid 
esters. The preferred fatty acids all result in esters which have melting 
points above 100.degree. F. and which easily crystallize upon cooling to 
temperatures below their melting point. The most preferred fatty acids for 
all esters are long chain (C.sub.16 -C.sub.22) saturated fatty acids. 
The mixture of esters to provide the ester vesicles contains diacetyl 
tartaric acid mono fatty acid glyceride ester at a level of from about 25% 
to about 75% by weight. All percentages used herein are by weight unless 
otherwise indicated. The second ester is also present at a level of from 
about 25% to about 75% by weight. The preferred mixture contains from 
about 60% to about 40% of each of the first ester and second ester. 
To prepare the aqueous compositions of the invention, it is important to 
provide a well blended homogeneous mixture of the dry powdered esters 
prior to dispersing the esters in water in a kettle. If necessary, when 
the ester is not a dry powder at ambient temperature, the ester may be 
frozen and ground to a powder while frozen. If the first and second esters 
are added individually to the water, the mixture does not form an aqueous 
gel. The mixture of esters are present in the water at a level of from 
about 2% to about 20%. The dispersion is stirred with a suitable mixer, 
such as a propeller mixer, as it is heated to a temperature of from about 
180.degree. F. to about 200.degree. F. over a period of from about 10 
minutes to about 30 minutes. The heated dispersion is then cooled to about 
130.degree. F. to about 150.degree. F. within 30 minutes while continuing 
stirring. The mixture can then be permitted to cool to ambient temperature 
without stirring. For very small batches of less than about 1000 grams, 
stirring can be discontinued as soon as it reaches the desired elevated 
temperature. At the elevated temperature, the composition is a white milky 
fluid which gels upon cooling. The mixture of esters forms a complex in 
the form of multilamellar vesicles upon cooling to refrigeration 
temperatures. The ester vesicles are dispersed as a matrix in the aqueous 
medium. Under microscopic examination, the vesicles resemble the structure 
of an onion which appears to have alternating hydrophobic and hydrophilic 
layers with water trapped between the layers. FIG. 1 clearly shows the 
structure and shape of the vesicles. The vesicles range in size from about 
1 micron to about 20 microns. 
The aqueous ester gel can also be used to prepare very stable foams having 
a high overrun of from about 200 to about 1200. The foams are stable 
enough to be frozen and thawed without undergoing syneresis. The foams can 
be used as is or can be combined with other food products to provide an 
aerated food product. Suitable food products for combining with the foams 
include yogurt, whipped topping base, ice cream base, cream cheese, 
tablespreads, gelatin desserts, puddings, peanut butter, salad dressings, 
process cheese spreads or any suitable fluid or gel type food product 
where an aerated texture is desired. 
The foams are prepared by diluting the aqueous gel, if necessary, with 
additional water to provide a foam base having from about 1% to about 5% 
ester mixture. The foam base is then whipped with a suitable mixer, such 
as a HobartTM food mixer provided with a wire whip, until the desired 
level of overrun is obtained. When very low levels of the ester mixture, 
i.e., from about 1% to about 3%, are present in the foam base, it is 
desirable to provide a bulking agent in the foam base. The bulking agent 
may be any of the commonly used food bulking agents, such as maltodextrins 
having a DE of from about 1 to about 20 and corn syrup solids having a DE 
of from about 20 to about 60. The bulking agent, if used is present in the 
foam base at levels of from about 20% to about 40%. 
The following examples further illustrate the compositions of the present 
invention, but are intended to in no way limit the scope of the invention 
as set forth in the appended claims 
EXAMPLE 1 
An aqueous ester vesicle composition was prepared. Equal parts of diacetyl 
tartaric acid monostearate and sucrose monostearate were homogeneously 
blended. The total amount of diacetyl tartaric acid monostearate glyceride 
used was 3%, the total amount of sucrose monostearate was 3% and the 
amount of water was 94%. 
The aqueous ester vesicle compositions were prepared by ading the blended 
esters and water into a kettle and heating the ingredients with vigorous 
stirring to a temperature of 190.degree. F. over a period of 20 minutes to 
provide a white milky fluid which gelled on cooling to refrigeration 
temperatures to provide ester vesicles. 
The ability of the ester vesicles of the present invention to incorporate 
air into products was demonstrated by making a fat free frozen whipped 
topping. The following formula was prepared: 
______________________________________ 
Ingredient Weight % 
______________________________________ 
Water 33.3 
Aqueous matrix* 33.3 
Corn syrup (DE 24) 
17.25 
High fructose 5.5 
corn syrup 
Sugar 5.35 
Inulin 3.1 
Dairy Lo 2.0 
Xanthan gum 0.2 
Vanilla flavor to taste 
______________________________________ 
*the aqueous ester matrix contained 3% diacetyl tartaric acid monostearat 
glyceride, 3% sucrose monostearate and 94% water. 
To prepare the frozen foamed whipped topping, the water and the aqueous 
matrix were placed in the bowl of a Hobart.TM. mixer. The inulin was 
sifted in and hydrated as the mixer was operated. The xanthan gum, sugar, 
dairy-lo were dry blended and then sifted into the mixture. The syrups 
were added along with the vanilla. Whipping continued with the Hobart.TM. 
mixer on maximum speed. Part of the product needed to be removed from the 
bowl of the Hobart mixer to make room for foam. The result was to provide 
10 cool whip tubs of product at approximately 700% overrun. 
EXAMPLE 2 
The present example demonstrates the ability of the aqueous gel of the 
present invention to provide a stable foam. An aqueous gel matrix 
containing 3% of diacetyl tartaric acid monostearate glyceride and 3% of 
sucrose monostearate was prepared in accordance with the procedure of 
Example 1. 
200 grams of the aqueous gel and 200 grams of water were placed in the bowl 
of a Hobart.TM. mixer equipped with a wire whip. After 5 minutes of 
whipping at the highest speed, a foam having an overrun of 700 was 
obtained. The foam was extremely stable and could be frozen and thawed 
without undergoing syneresis. When the individual esters without being 
formed into an aqueous gel matrix were added to water at the same level 
(3% total ester), a foam could not be attained. 
EXAMPLE 3 
Various aqueous compositions of esters were prepared in accordance with the 
procedure in Example 1 wherein the total amount of emulsifier was 6%. With 
the exceptions noted below, emulsifiers were thoroughly mixed by 
dry-blending prior to introduction into aqueous medium. For Variant 2, 
which contained decaglycerol monostearate, cryo-grinding with dry ice was 
required to uniformly blend the emulsifiers. For Variant 5, the 
polyoxyethylene sorbitan monostearate component was melted at 90.degree. 
F. prior to mixing the two emulsifiers. After forming the vesicles or 
complexes, the emulsifier compositions were cooled at 45.degree. F. for at 
least 16 hours. 
To make foams, 100 g of each of the variants was mixed with 100 g of water 
and 100 g of sucrose, thus providing 3% of the esters in the mixture. The 
mixtures were placed in a bowl of a Hobart.TM. mixer equipped with a wire 
whisk. The mixtures were mixed for 1 minute on the lowest speed, followed 
by 3 minutes on the highest speed. Overrun was measured as the percent 
volume of air per weight of mixture. Compositions and overruns are shown 
in the table below. 
__________________________________________________________________________ 
m.p. 
Var 1 
Var 2 
Var 3 
Var 4 
Var 5 
Var 6 
Var 7 
Ingredients 
HLB 
(.degree. F.) 
(%) (%) (%) (%) (%) 
(%) 
(%) 
__________________________________________________________________________ 
Diacetyl tartaric 
8 140 3.0 4.0 3.0 -- 3.0 
-- -- 
acid 
monostearate 
glyceride 
Sucrose 16 133 3.0 -- -- 3.0 -- -- 3.0 
monostearate 
Decaglycerol 
13 126 -- 2.0 -- -- -- -- -- 
monostearate 
Sodium stearoyl 
.about.12 
113 -- -- 3.0 -- -- 3.0 
3.0 
lactylate 
Glycerol 4 162 -- -- -- 3.0 -- -- -- 
monostearate 
Polyoxyethylene 
15 86 -- -- -- -- 3.0 
-- -- 
sorbitan 
monostearate 
Sucrose 9 113 -- -- -- -- -- 3.0 
-- 
stearate.sup.1 
Water -- -- 94.0 
94.0 
94.0 
94.0 
94.0 
94.0 
94.0 
Overrun of 
-- -- 1020 
1050 
1200 
1030 
536 
none 
none 
mixture (%) 
__________________________________________________________________________ 
.sup.1 Ryoto 5970 
Variants 1, 2 and 3 aerated very rapidly. After 1 minute of whipping, they 
had achieved almost maximum air incorporation. The resulting foams from 
variants 1, 2 and 3 appeared dry and were stable after several weeks in 
the refrigerator with no drainage. 
Variants 4 and 5 were much slower to aerate, incorporating very little air 
until after 2 minutes of whipping. Foams from Variants 4 and 5 were soft 
and wet. Microscopically, the air cells of foams from variants 4 and 5 
were much larger than those from variants 1, 2 and 3. Although the overrun 
of foam from variant 4 was similar to those from variants 1, 2 and 3, it 
was a weaker foam. After several days, the foam made with variant 4 became 
very open in texture. After 1 week of storage, the foam showed 
considerable drainage and collapse. The foam made with variant 5 was even 
weaker than that made with variant 4, showing drainage and collapse after 
only 1 day of storage. 
Variants 6 and 7 did not incorporate any air even after prolonged whipping 
at high speed. 
This example illustrates the unique benefits of compositions containing 
diacetyl tartaric acid monostearate glyceride and a high HLB emulsifier 
with m.p.&gt;100.degree. F. (variants 1, 2 and 3). Although foams could be 
formed with variant 4 (a low HLB emulsifier and a high HLB emulsifier with 
m.p.&gt;100.degree. F.) and variant 5 (diacetyl tartaric acid monostearate 
glyceride and a high HLB emulsifier with m.p.&lt;100.degree. F.), both were 
weak foams. Complexes of two high or medium HLB emulsifiers which did not 
contain diacetyl tartaric acid monostearate glyceride (variants 6 and 7) 
were not able to incorporate air.