BACKGROUND OF THE INVENTION
1. Field of the Invention.
The present invention relates, in general, to frozen dairy products. More particularly,
the present invention relates to formulations and methods for producing frozen dairy
products for dessert use that have surprising stability, organoleptic, and body
2. Statement of the Problem.
Frozen dairy products enjoy great popularity. Many variations of frozen dairy
products have been developed for dessert use, including ice cream, whipped toppings,
and soft-serve products. Soft-serve products are particularly popular and have a
wide appeal. Distinguishing features of conventional soft serve products are that
they are frozen in a special soft-serve freezer, are dispensed by extrusion at carefully
chosen subfreezing temperatures, and generally stand up on a cone or dish upon extrusion.
Conventional soft-serve products are usually dispensed at an overrun on the order
of 40% to 60%. Although soft-serve products of this character have been marketed
for many years, they are still available only from stores having special freezers
that dispense the product for immediate consumption. This is because the product
generally is dispensed at temperatures between 16°F and 24°F. At lower
temperatures, the product is no longer sufficiently soft. Thus, conventional soft-serve
products are not suited for sale from grocery store freezers for home storage and
use. Home freezers maintain temperatures generally around -18°C to -12°C
(0°F to 10°F), and store freezers, which as used herein includes grocery
store, supermarket, and restaurant freezers, are generally at colder temperatures.
Others have expended considerable effort to develop a soft-serve
product for home use, but apparently with little success. A search of the prior
art concerning such frozen dairy products discovered the following patents:
Rivière et al.
Aug. 28, 1997
Morley et al.
Morley et al.
Aug. 23, 1983
Tapfer et al.
Jan. 9, 1996
Nov. 25, 1997
Cole et al.
June 5, 1984
Zobel et al.
Oct. 23, 1984
Gonsalves et al.
Dec. 31, 1991
Martin et al.
Dec. 15, 1992
Martin et al.
Oct. 25, 1994
Kahn et al.
Dec. 20, 1983
Greenberg et al.
June 20, 1989
PCT Patent No. WO 97/30600
to Rivière et al. teaches a compound that is "spoonable" at -18°C
to -24°C (-0.4°F to -11.2°F) and that contains 6 to 18 wt% milk proteins
(as skim milk or dried milk powders), 6 to 24 wt% fat, 20.3 to 24.6 wt% carbohydrates
(8.2 to 13.3 wt% dextrose, 3.3 to 8.2 wt% invert sugar, and 7.0 to 8.2 wt% glucose
syrup), 0.25 to 0.8 wt% stabilizer, and 49 wt% liquid skim milk. The overrun is
50 to 200%. The Rivière patent relies on vegetable fat with a very low melting
point, specifically sunflower oil, to achieve the softness or spoonability set forth.
There is a further reliance on the use of emulsifiers (mono- and diglycerides) to
provide the whipability, desirable texture, and shelf life characteristics of this
U.S. Patent Nos. 4,346,120
to Morley et al. teach a soft-serve compound. Patent 4,346,120 shows a
compound with 5 to 15 wt% milk solids non-fat (MSNF), 5 to 15 wt% fat, 20 to 40
wt% carbohydrates, 0.25 to 1.3 wt% stabilizer, 0.2 to 0.8 wt% emulsifier, and 43
to 65 wt% water. The overrun is between 110 and 220%.
U.S. Patent No. 4,400,406
is a continuation in part of the 4,346,120 patent that has different ranges:
protein is between 3 and 7 wt%, fat is at 3 to 15 wt%, carbohydrates are at 18 to
30 wt%, stabilizer is at 0.35 to 1.0 wt%, water is at 43 to 65 wt%, and emulsifier
is at 0.2 to 0.8 wt%. The overrun is between 100 and 220%. The Morley patent relies
upon providing a saccharide system containing various sugars, a stabilizer system
employing at least one stabilizer from each of at least three groups of stabilizers,
and an emulsifier system having particular emulsifiers to provide an extrudable
product at home freezer temperatures (0°F to 10°F). The carbohydrates
used include fructose, sorbitol (a sugar alcohol), and corn syrup. The presence
of the sorbitol is justified by a need to compensate for the excessive sugary taste
imparted by the fructose.
U.S. Patent No. 5,482,728 (to Tapfer et al.
) teaches "hard" ice cream compositions containing 10 to 12.19 wt% MSNF,
5 to 14 wt% milk fat, 12.99 to 18.48 wt% carbohydrates as sugars encapsulated in
fat, 0.29 to 0.34 wt% stabilizer/emulsifier, and 58.28 to 69.48 wt% water. The overrun
is 50%. The key to the Tapfer et al. results is their method in which the sugar
components are encapsulated in fat before use.
U.S. Patent No. 5,690,983
(to Sponholtz) discloses an unfrozen expanded ice cream mix having 10.70
wt% MSNF, 8.00 wt% milk fat, 8.00 wt% sucrose, 7.0 wt% dextrose, 2.55 wt% stabilizer-emulsifier
mix (Mixture TS-D 434), and 4.5 wt% flavor, for a total solids content of 42.75
wt%. The composition forms a liquid aerated mix with an overrun of 90% that can
be stored at non-freezing temperatures.
U.S. Patent No. 4,452,824
(to Cole et al.) teache a soft-serve composition containing 2 to 10 wt%
MSNF, 2 to 15 wt% milk fat, 24 to 34 wt% carbohydrates, 0 to 2 wt% stabilizer, 0.2
to 1.0 wt% emulsifier, and 45 to 65 wt% water. The carbohydrates are distributed
in a critical combination so that the ratio of higher saccharides to mono- and disaccharides
(ratio 1) and the ratio of disaccharides to monosaccharides (ratio 2) satisfy the
relationship of 11 (28 x ratio 1) + ratio 2 28. The overrun is 50 to 200%.
U.S. Patent No. 4,478,867 (to Zobel et al.
) teaches a process for whipping an emulsion. The emulsion contains 2 to
30 wt% nonfat dry milk, 18.0 to 30.0 wt% vegetable fat, 20.0 to 30.0 wt% carbohydrates,
0.01 to 2.0 wt% stabilizer, 0.5 to 2 wt% sodium caseinate, 0.4 to 2.0 wt% emulsifier,
and 40 to 60 wt% water. The overrun is 200 to 350%. This emulsion has a texture
similar to that of whipped cream (Cool Whip®).
U.S. Patent No. 5,077,076 (to Gonsalves
) teaches a formula for a whipped topping. The topping is comprised of
2.5 to 7.0 wt% MSNF, 5 to 15 wt% fat (either vegetable fat or milk fat), 15 to 25
wt% carbohydrates, 0.05 to 1.0 wt% stabilizer, 0.5 to 2 wt% sodium caseinate, 0.15
to 0.6 wt% emulsifier, 0.03 to 0.15 wt% phosphate salts, and 57 to 62 wt% water.
The overrun is more than 250%. This topping also has a texture similar to that of
whipped cream (Cool Whip®).
U.S. Patent No. 5,171,602 (to Martin et al.
) discloses a nonfat composition for a dessert product consisting of 8
to 18 wt% MSNF, 12 to 36 wt% carbohydrates, 0.5 to 3.0 wt% starch, and the balance
being water. There is no fat, stabilizer, or emulsifier. The overrun is 80 to 100%.
U.S. Patent No. 5,358,728 (to Martin et al.
) is similar to
Patent No. 5,171,602
, except that 0.03 to 0.3 wt% polyphosphate compounds are added.
U.S. Patent No. 4,421,778 (to Kahn et al.
) teaches compounds that contain a premix comprising 10 to 30 wt% fat,
3.5 to 20 wt% emulsifier, 6 to 34 wt% stabilizer, and the balance being a protein
carrier, such as MSNF, dairy whey, whey protein, and/or a carbohydrate carrier.
The basic composition is described as an oil-in-water emulsion of 3.00 wt% premix,
10.85 wt% protein, 24.00 wt% carbohydrates, 54.24 wt% water, 0.50 wt% flavor, and
7.41 wt% fat, of which at least 50% is a solid beta phase-tending crystalline fat
(such as lauric fats, coconut oil, palm kernel oil, palm oil, etc.) that prevents
the formation of crystalline surfaces. The overrun is 70 to 130%.
U.S. Patent No. 4,840,813 (to Greenberg et al.
) discloses a product having 4.0 to 7.2 wt% casein and 1 to 7 wt% whey.
It is required by this patent to have a whey:casein ratio from 1:0.5 to 1:4. The
product also includes 0.1 to 9.0 wt% fat, 14 to 18 wt% carbohydrates, 0.5 to 2 wt%
ash, 0.1 to 5.0 wt% flavor, and 55 to 65 wt% water. The overrun is 40 to 100%.
In these prior formulations, it has been common to obtain
a soft-serve type of product by the use of sugar alcohols, emulsifiers, vegetable
fats, and other additives, all of which may add undesirable tastes or mouth sensations
to the frozen dairy product. In other formulations, a soft-serve type of product
has only been obtainable through the use of complex formulations and ratios of ingredients,
or by complicated methods. To achieve different flavors or different types of products,
additional ingredients must be added. None of the above references has provided
a product having commercial success as a soft-serve ice cream type of product for
SUMMARY OF THE INVENTION
The present invention is directed to frozen dairy products
having desirable texture and that are soft and scoopable at home freezer temperatures
(that is, at about -18°C (0°F) to about -15°C (5°F)) with unique
organoleptic properties. The present invention also provides frozen dairy products
that have a long shelf-life and that have an overrun of about 200%. In addition,
the present invention provides for different embodiments of frozen dairy products,
such as yogurt-like and custard-like. All of these characteristics are obtained
by the present invention with simple and straightforward formulations that do not
include sugar alcohols or vegetable fats. Further, emulsifiers may or may not be
used, and preferably are not used in the present invention.
The frozen dairy product of the present invention is formulated
with ingredients that provide fat, protein, water, sweeteners, and stabilizer constituents
in a combination that permits the attainment of the desirable properties described
above. The attainment with these ingredients of these properties is deemed unexpected
and not predictable.
The frozen dairy product of the present invention preferably
comprises, on a weight basis, about 10% to about 13% milk solids non-fat (MSNF),
about 4% to about 16% milk fat, about 5% to about 10% sucrose, about 2% to about
8% corn syrup having a DE of about 36, about 4% to about 12% dextrose, up to about
1.5% starch, and about 0.2% to about 1.0% stabilizer.
One particular feature of the frozen dairy products of
the present invention is the ability to be aerated with significantly more air than
is common for frozen dessert products. In the ice cream and soft serve industries,
the amount of air in a product is described as "overrun." Overrun measures the percentage
by which the volume of the liquid mix for a product is increased with air during
whipping and freezing. The overrun of the frozen dairy product of the present invention
is about 200%. It is unexpected for the formulation of this product to be able to
attain such an overrun and produce a product with satisfactory shelf life/stability.
A method for production of the frozen dairy products as
defined above is also provided by the present invention. In this method, a first
mixture is prepared by adding the sucrose, corn syrup, dextrose, starch and stabilizer
to heated water with agitation. The milk fat and milk solids non-fat are then added
to the first mixture to form a final mixture. The final mixture is agitated for
a time to thoroughly mix the ingredients. The final mixture is then pasteurized
and homogenized. After these steps, the final mixture is aerated to an overrun of
about 200% in a scrape surface heat exchanger, extruded, and packaged by conventional
methods. The packaged mixture is then hardened for a predetermined period of time
at -34°C (-30°F). Unlike previous methods for producing frozen dessert
products, there is no "mix maturation" step.
Accordingly, it is an object of the present invention to
provide frozen dairy products having a desirable texture and unique organoleptic
properties. It is another object of the present invention to provide frozen dairy
products that are soft and scoopable at about -18°C (0°F) to about -15°C
(5°F). It is an object of the present invention to provide frozen dairy products
that can be produced in both regular and low-fat formulations and in a variety of
product types without the addition of separate flavor ingredients. It is a further
object of the present invention to provide methods for producing frozen dairy products.
These and other advantages, features, and objects of the
present invention will be more readily understood in view of the following detailed
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides frozen dairy products that
are soft and scoopable at about -18°C (0°F) to about -15°C (5°C)
have a stable through shelf-life, and incorporate a significant amount of air (up
to about 200% overrun) while also having unique (creamy) organoleptic properties.
Methods of production for the frozen dairy products are also disclosed herein. The
frozen dairy products can be produced by the methods in a variety of embodiments,
such as ice cream-like, low-fat ice cream-like, low-fat yogurt-like, and custard-like.
Each of these embodiments can be further flavored, for example, with cocoa or other
liquid flavor ingredients, or can support the addition of other edible materials,
such as fruit, nuts, or candy pieces, for example.
Throughout the specification and claims, percentages and
ratios are by weight and temperatures are in degrees Fahrenheit unless otherwise
The frozen dairy products of the present invention generally
contain milk solids non-fat, milk fat, sucrose, corn syrup having a DE of about
36, dextrose, stabilizer and starch.
The amount and exact character of each ingredient will
depend upon such factors as the character of the other ingredients and the desired
nature of the end product. For example, the amount of fat is varied to provide regular
and low-fat frozen dairy products. In one embodiment, a soft textured ice cream-like
product is provided. In another embodiment, the milk solids non-fat are cultured
with bacteria to a predetermined acidity, which provides a frozen yogurt-like product.
In a further embodiment, egg yolk is added to provide a frozen custard-like product.
In an important embodiment, the composition of the present
invention that can be used to prepare frozen dairy products generally has the following
components as set forth in Table I.
Milk solids non-fat
Corn syrup (about 36 DE)
2 - 8
up to 1.5
Milk solids non-fat as used in the preferred compositions
of this invention can be derived from cream, milk (including condensed milk, skim
milk, and condensed skim milk), and non-fat dry milk. Milk solids non-fat aid in
providing the desirable properties of whipability, smoothness, body, mouthfeel,
and melt resistance.
The milk fat ingredient aids in providing a creamy taste
and the eating characteristics associated with ice cream-like products. It also
contributes to the smoothness, the body, and the melting resistance of the frozen
dairy products. Dairy cream and milk are the preferred fat sources.
The sweetener ingredients preferably are a combination
of sucrose, dextrose, and corn syrup that provide a desired level of sweetness and
texture to the frozen dairy products. The combination of dextrose, sucrose, and
corn syrup also serves to decrease the freezing point of the mixture. It is postulated
that the freezing point depression decreases viscosity, thus allowing for uniform
and stable incorporation of air. The corn syrup preferably has a dextrose equivalent
(DE) of about 36, which is in the low DE range of corn syrups. Corn syrups possessing
a DE of about 24 to about 42 can be used in this invention. Corn syrup of 36 DE
is preferred for ease of processability and satisfactory low-molecular-weight sugar
composition. In addition, high-fructose corn syrup can be used.
The stabilizer ingredient may also contribute to the attainment
of the desired features of the new frozen dairy products. The stabilizer ingredient
is used to improve the ability of the products to withstand commercial shelf life
and substantial heat shock without undue deterioration, such as a loss of overrun.
The stabilizer ingredient may include vegetable gums and, in a preferred embodiment,
the stabilizer ingredient is selected from the group consisting of locust bean gum,
guar gum, and carrageenan. Other stabilizers may be appropriate for use in the present
invention, and such stabilizers will be evident to those skilled in the art and
are meant to be included in this description of the frozen dairy products.
Water is present in the new frozen dairy products as a
dispersion medium for the other ingredients of the emulsified product. The portion
of water in the product is determined on an "as needed" (q.s.) basis to provide
the balance of the mixture with reference to a total weight of 100% after the weights
of the other ingredients are taken into account. The portion of water in the products
that remains unfrozen provides fluidity for the product. The portion of water that
does freeze forms ice crystals that give the product rigidity as well as the refreshing
taste perception characteristic of a frozen dessert.
A flavor ingredient can be added to these ingredients if
desired. The flavor ingredient is selected from known flavors according to the desired
taste, taking into account the other ingredients. Flavor ingredients include, by
way of illustration, liquid flavor ingredients such as vanilla, vanilla extract,
cocoa, and mint, and solid flavor ingredients such as fruits, nuts, candy, chocolate-
and peanut-flavored chips and the like, as well as other flavor ingredients. The
present invention provides frozen dairy products with a stable matrix that will
hold unexpectedly large amounts of such flavor ingredients. For example, cocoa is
added at up to about 3.5% to provide a chocolate flavor. Fruit and nuts can be added
from about 0% to about 40% usage by weight. Note, however, that the ingredient ranges
specified herein, unless stated otherwise, are for an unflavored product. Those
skilled in the art will comprehend the adjustments appropriate for the particular
flavor ingredient used. Of importance to the present invention, different embodiments
of the frozen dairy products exist that are not dependent on the addition of flavor
ingredients, such as yogurt-like or custard-like products (see examples below).
In addition to the foregoing ingredients, the frozen dairy
products of the present invention can include other ingredients if desired, such
as, for example, starches.
Any modified food starch, such as, for example, corn starch,
potato starch, rice starch, or tapioca starch, can be used. The starch used in the
compositions of the present invention is preferably modified corn starch. Modified
starches, when used at low levels (less than about 2%), offer improved texture (creaminess)
and improved shelf-life (stability) to the frozen dairy products. It is thought
that starch molecules organize water in fashion similar to that of hydrocolloid
(stabilizer) molecules by obstructing ice crystal growth and/or changing the morphology
of ice crystals. In addition, starch may enhance the whipability and air incorporation
in the frozen dairy products by strengthening the solids matrix surrounding the
In order to achieve the frozen dairy products of the present
invention, a particular method is preferably used. In a preferred method of the
present invention, the water required is added to a kettle provided with an agitating
device. The preferred agitating device is a Lanco/Breddo™ high
shear mixer/liquefier that is preferably operated at its highest speed. The water
is heated to a temperature of from about 49°C to about 54°C (about 120°F
to about 130°F).
The order of addition of the individual ingredients is
important to obtain uniform blending of the ingredients. The following order of
addition is preferred. The sucrose, corn syrup, dextrose, stabilizer, and starch
are added to the heated water, and agitation is commenced and continued for a period
of from about 30 seconds to about 4 minutes, preferably about 2 minutes, to form
a first mixture. The milk fat and milk solids non-fat are then added and agitation
is continued for an additional about 30 seconds to about 4 minutes, preferably about
2 minutes, to form a final mixture.
The final mixture is then pasteurized under suitable time
and temperature conditions, preferably at a temperature of from about 82°C
(180°F) to about 93°C (200°F) for a hold time of about 30 to about
120 seconds, followed by regeneration and cooling to about 4°C (40°F).
In another embodiment the final mixture is pasteurized by vat between about 74°C
(165°F) to about 77°C (170°F) for about 30 minutes, followed by similar
regeneration and cooling to about 4°C (40°F).
The pasteurized final mixture is then homogenized in a
conventional two-stage homogenizer. In a preferred embodiment, homogenization comprises
a first stage performed at a pressure of about 3.45 MPa (500 psi) to about 10.34
MPa (1,500 psi) and a second stage following the first stage, with the second stage
performed at about 13.79 MPa (2,000 psi) to about 34.47 MPa (5,000 psi).
After pasteurization and homogenization, the final mixture
is flavored, aerated in a scrape surface heat exchanger, extruded, and packaged
by conventional methods. The aerated final mixture has an overrun of about 200%.
The packaged mixture is then hardened at about -34°C (30°F) for about
6 hours to about 18 hours before distribution.
Once the frozen dairy products are prepared by the above
method, they can be stored for about 2 weeks to about 4 weeks at either store freezer
or home freezer temperatures and also resist considerable temperature variations,
such as that which occurs between the time the product is purchased from a store
until the product is placed in a home freezer, without significant loss of their
Of importance to the present invention, the desired properties
of a soft texture that is scoopable at about -18°C (0°F) to about -15°C
(5°F), unique organoleptic properties, a stable shelf-life, and the ability
to hold an overrun of about 200% are obtained in the frozen dairy products of this
invention with the use of the above-described ingredients in a straightforward combination
and method of production. These results are deemed unexpected and advantageous,
in that other ingredients such as emulsifiers, complex ratios of ingredients, and
additional, time-consuming steps, such as a mix maturation step in which the product
is held at a predetermined temperature for up to 24 hours before freezing, have
generally been necessary in previous frozen products in order to achieve some of
these desirable results.
The individual ingredients comprising the compositions
of the invention may be varied in quantity to obtain embodiments of frozen dairy
products having different flavor and textural sensations without the use of additional
flavor and textural ingredients as described above. The following examples further
illustrate various features of the present invention that are intended to in no
way limit the scope of the invention that is defined in the appended claims.
A batch of frozen dairy product was made by the above-described
method using the following components at the indicated levels:
Milk solids non-fat
5 - 16
5 - 8
Corn syrup (about 36 DE)
3 - 6
5 - 9
up to 1.5
0.2 - 1.0
In this example, the resulting frozen dairy product has
a soft texture and a taste similar to that of ice cream. If desired, cocoa or other
liquid flavor ingredients can be added at up to 3.5% as described above.
In this example, the frozen dairy product has a soft texture
and a taste similar to that of a frozen yogurt. This embodiment is also low in fat.
Milk solids non-fat
5 - 10
Corn syrup (about 36 DE)
4 - 8
4 - 12
0.5 - 1.5
0.65 - 1.0
In the method for producing the frozen dairy product of
Example 2, a portion of the ingredients is first cultured with bacteria to provide
the yogurt-like product of this embodiment. That is, in this particular method,
a culture mixture is first prepared by heating water to a temperature of about 49°C
(120°F) to about 54°C (130°F) and adding a portion of the milk solids
non-fat, that is, about 5% to about 10% of the total milk solids non-fat, to the
heated water to form a first mixture. This first mixture is then pasteurized and
cooled to about 43°C (110°F). Bacteria are then added with agitation for
about 30 minutes. The first mixture with the bacteria is then incubated at about
43°C (110°F). For about 2 hours to about 6 hours until it reaches about
1.10 titratable acidity. Titratable acidity is defined as percent acid (by weight)
in a given sample.
The bacteria used for culturing the culture mix are selected
from the group consisting of Lactobacillus acidophilus, Bifidobacterium longum,
Streptococcus salivarius subsp. thermophilus, and Lactobacillus delbruckii
subsp. bulgaricus. Other species of bacteria capable of culturing the culture
mix may be known to those skilled in the art and are meant to be included in the
In the next step, a sugar mixture is prepared by heating
water between about 49°C (120°F) and about 54°C (130°F) and
adding the remainder of the milk solids non-fat, milk fat, sucrose, corn syrup,
dextrose, starch, and stabilizer to the heated water with agitation to form a second
mixture. The second mixture is then pasteurized as described above.
The culture mixture having a titratable acidity of about
1.10 is then blended with the sugar mixture to form a final mixture. Preferably,
the culture mixture is blended with the sugar mixture in a 32.5%/67.5% volume/volume
ratio, but other ratios can be used under the present invention as will be known
to those skilled in the art. The final mixture is then aerated in a scrape surface
heat exchanger, extruded, packaged, and hardened at about -34°C (-30°F)
as described above to provide a frozen yogurt-like product. As for Example 1, flavor
ingredients can be added to the final mixture to provide desired flavors for the
yogurt-like frozen dairy product.
In this embodiment of the present invention, the frozen
dairy product is similar to a low-fat ice cream with a soft texture.
Milk solids non-fat
10 - 13
5 - 10
5 - 10
Corn syrup (about 36 DE)
2 - 4
4 - 10
0.5 - 0.75
0.65 - 1.0
In this embodiment, the method of Example 1 is used to
prepare the product. Flavor ingredients can be added if desired.
In this embodiment, the frozen dairy product has a soft
texture, is low in fat, and resembles a custard-like product.
Milk solids non-fat
5 - 7
Corn syrup (about 36 DE)
2 - 6
4 - 10
0.65 - 1.0
0.65 - 1.0
1.4 - 2.0
In the method for this embodiment, the egg yolk is added
to the heated water along with the sweeteners, stabilizer, and starch (if present)
and agitated for about 30 seconds to about 4 minutes, preferably for about 2 minutes,
in order to combine the egg yolk thoroughly before pasteurization. As before, flavoring
ingredients can be added if desired.
Thus, the present invention provides for frozen dairy products
having desirable textural and unique organoleptic properties, such as being soft
and scoopable at about -18°C (0°F) to about -15°C (5°F) being
capable of being aerated to an overrun of about 200%, providing a variety of embodiments,
such as ice cream like, yogurt-like, and custard-like, and maintaining these desirable
properties during a long shelf life. These results are unexpected when using the
ingredients and methods specified herein.
The foregoing discussion of the invention has been presented
for purposes of illustration and description. Further, the description is not intended
to limit the invention to the form disclosed herein.