WO2004028260A1

WO2004028260A1 - Ultra-high temperature pasteurized milk concentrate, package, dispenser and method of producing same

Info

Publication number: WO2004028260A1
Application number: PCT/US2003/028457
Authority: WO
Inventors: Ronald A. Reaves; Ronnie L. Howard
Original assignee: Moo Technologies, Llc
Priority date: 2002-09-25
Filing date: 2003-09-11
Publication date: 2004-04-08
Also published as: US6887505B2; US20030054079A1; AU2003272318A1

Abstract

An ultra-high temperature pasteurized liquid (UHT) milk concentrate provides a reconstituted milk beverage that tastes like fresh milk having a flavored, sweetened or juice note. A direct steam injection process is used to form the UHT milk concentrate having at least about 30 % by weight, preferably 35 % to 45 % by weight, nonfat milk solids having a shelf stability of at least 30 days. The UHT milk concentrate is homogenized and aseptically packaged for subsequent mixing in conventional beverage dispensers with water at volume ratios of about 3:1 to 4:1 of water to concentrate to make a beverage that tastes like fresh milk having a flavored, sweetened or juice note.

Description

ULTRA-HIGH TEMPERATURE PASTEURIZED MILK CONCENTRATE, PACKAGE. DISPENSER AND METHOD OF PRODUCING SAME

RELATED APPLICATIONS

This application is a continuation-in-part application of U.S.

Application Serial No. 09/850,983, filed May 8, 2001 , which in turn is

a continuation of U.S. Application Serial No. 09/433,365, filed

November 3, 1 999, now abandoned. The entire disclosures of these

applications are incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to producing and packaging an ultra-

high temperature pasteurized milk concentrate for dilution with water and

dispensing as reconstituted milk having a fresh taste and having a

flavored, sweetened or juice note.

BACKGROUND OF THE INVENTION

The cost of transporting and storing fresh milk is significant

because of its short shelf life and weight. Because fresh milk is used extensively by America's military and is one of its largest export

commodities, there is a long-felt need for a milk concentrate that has a

longer shelf life, a product package with a lesser weight for transportation

and storage, and that provides the same physical and taste characteristics

of fresh milk when reconstituted.

The prior art addresses various aspects of the UHT

pasteurization of milk, the production of condensed milk products, and

the reconstituting of concentrated liquid beverages. No known prior art,

however, discloses an ultra-high temperature pasteurized liquid milk

concentrate which may be packaged for dispensing as a reconstituted

milk beverage in existing beverage dispensers or for transporting large

amounts of UHT pasteurized milk concentrate worldwide to provide a

reconstituted milk at the destination that has the same physical

characteristics of and tastes like fresh milk.

U.S. Patent 2,860,057 discloses a known preparation of a

sterilized evaporated or condensed milk having a final desired

concentration of from about 1 6% to 35% total solids compared to the

standard concentration of about 8.0-8.5% total solids. The different

processes each involve forewarming and pasteurizing steps including

high-temperature-short-term sterilization after the milk is first

concentrated by conventional means. The disclosed processing avoids

age thickening or gelation of the milk during high-temperature sterilization

effected either before or after packaging in a can. If an aseptic canning method is used, the sterilized concentrate is subsequently homogenized

under sterile conditions. Reconstitution involves a complicated dilution,

mixing, and color comparison procedure with disclosed mixing volume

ratio of water to evaporated milk of 1 : 1 .

U.S. Patent 4,921 ,71 7 describes a process for producing

UHT sterilized concentrated milk including first sterilizing a partially

concentrated milk product and then effecting further concentration of the

milk product under sterile conditions. U.S. Patent 4,842,884 describes

a formulated milk concentrate made with a mixture of nonfat dry milk

solids, water, edible oil and sugar. The concentrate can either be frozen

for later use or immediately blended with water to produce a beverage.

Once reconstituted, it may be stored for up to about 5 days.

U.S. Patents 2,570,231 ; 3, 108,875; 4,362,756; and

5,766,666 respectively disclose a sweetened condensed skim milk,

condensed cream, condensed milk having at least 8% milk fat, and a

reduced fat and/or fat-free condensed milk each processed differently to

produce a novel sweetened condensed dairy product in each instance.

The condensed cream is used for a source of fat in ice cream. The other

three condensed milk products are used in the baking and confectionary

industries and by retail consumers to produce baked goods. U.S. Patent

4,091 , 1 1 8 describes a vegetable-based sweetened condensed milk used

as a coffee creamer. U.S. Patent 2,565,085 discloses the customary forewarming

of whole milk to destroy bacteria, molds, yeasts, and the like. The

forewarming also helps to maintain the texture of the milk product. Such

forewarming of the milk is usually effected at a temperature in the range

of 145°F to 1 75°F. U.S. Patent 5,260,079 describes a method of and

equipment for controlling the content of fat in milk using specified

process parameters for mixing skim milk with cream. U.S. Patents

5,223,299 and 5,229, 1 59 disclose sterilizing milk without stabilizers and

a packaged resultant milk concentrate product for use as coffee

creamers. U.S. Patent 4,282,262 discloses a milk blend fraction used as

an ingredient component for a two-packet frozen dessert. The milk blend

includes sodium hexametaphosphate and carrageenan used together as

stabilizers.

In brief, in prior practice ultra-high temperature pasteurized

(UHT) milk often had a "scor ched" or "burnt" milk taste as a result of

the extremely high temperature to which the milk is heated in the UHT

process. Milk is an extremely heat-sensitive product, in part, because it

contains proteins which become denatured at higher temperatures. Such

denaturing of the milk results in the scorched milk flavor whereby it loses

its fresh milk taste. While improvements have been made in UHT

processing for regular strength solids UHT milk products prior to this

invention, it was commonly believed in the dairy industry that the

problem of scorching would increase as the solids level in milk increases because, in such a concentrated environment, milk proteins would be

more susceptible to denaturing at higher temperatures. Known

concentrated milk with high milk solids also has a natural tendency

to separate or granulate and turn to gel upon aging. Moreover,

reconstitution of such a concentrated milk also may lead to granulation

and product separation, thus destroying the taste and mouth feel of

regular fresh milk.

SUMMARY OF THE INVENTION

This invention is directed to ultra-high temperature

pasteurized (UHT) liquid milk concentrates and methods for producing

them. The invention also provides an aseptic UHT milk concentrate

package and dispenser for reconstitution with water and dispensing as a

fresh milk product.

The objectives and benefits of this invention are achieved by

providing a condensed liquid milk blend which includes a stabilizer and a

pasteurized liquid milk concentrate having an amount of nonfat milk solids

sufficient to produce the UHT liquid milk concentrate having a nonfat milk

solids content of at least about 29.9% (i.e., about 30%) by weight when

the UHT milk concentrate is reconstituted with water. It has been found

that such a high solids liquid milk concentrate may be converted into a

UHT milk concentrate by directing a continuous flow of a condensed milk

blend into direct contact with steam. The steam is injected directly into

the continuous flow of the milk blend at an effective ultrapasteurizing temperature sufficient to form the UHT milk concentrate having a nonfat

milk solids content of at least about 30% by weight.

The UHT liquid milk concentrate upon reconstitution with

water, at water to concentrate volume ratios in the range of about 3: 1 to

4: 1 , tastes like regular fresh milk. The UHT liquid milk concentrate has

(a) an extended shelf stability of at least about 30 days without

granulation and/or separation, (b) milk solids which do not separate upon

dilution with water, and (c) upon dilution provides a drinkable product

which tastes like fresh milk.

Among the other advantages achieved by this invention, the

UHT concentrated milk is packaged under aseptic conditions and used in

currently available dispensing machines. Other benefits in transportation,

military use, commercial and other food service programs are achieved.

Other advantages and objectives of this invention will be further

understood with reference to the following detailed description.

DETAILED DESCRIPTION OF THE INVENTION

A primary purpose of this invention is to provide an ultra-

high temperature pasteurized concentrated liquid milk that has a shelf life

of at least about 30 days and, upon dilution with about 3 to 4 volumes

of water, the milk solids do not separate and the diluted concentrate has

an acceptable taste profile like fresh milk. The stability is obtained

without granulation and/or separation of solids, i.e., a lack of

sedimentation or crystallization of solids. Hereinafter the ultra-high temperature concentrated liquid milk is sometimes simply referred to as

"ultrapasteurized milk concentrate" or "UHT milk concentrate".

The term "fresh" as applied to milk herein means

characteristics normally associated with fresh, pasteurized milk, whether

it is in the categories of Fat Free, or skim (less than 0.21 % fat), Low Fat

(1 % fat), Reduced Fat (2% fat), or Full Fat (3.25% fat). These milk

products are purchased at a store by a consumer who recognizes them

as fresh. Consumers have recognition of the inventive products as fresh,

as compared to, for example, products such as canned or condensed

milk, reconstituted powdered milk, UHT milk, and the like. A consumer

would recognize these latter-mentioned products as not fresh. In addition

to the consumer test for freshness presently employed in this invention,

other sensory tests may be employed to give a sensory description of the

inventive milk product. Such other tests usually evaluate the major

sensory characteristics of fresh milk which include (a) the presence or

absence of visual defects, whether it has visibly separated or coagulated,

or changed in color, (b) the aroma and taste, which together contribute

to the flavor, and (c) the texture and mouth feel, i.e., free of milk defects

which may be described as watery, thin, coagulated, sandy, gritty, or

separated.

An extended shelf stability or life of at least about 30 days

means that the milk has an acceptable taste profile of fresh milk when

either (a) it is held or stored at a temperature of less than about 45°F according to the Public Health Service/Food and Drug Administration

Publication No. 229, entitled, "Grade A Pasteurized Milk Ordinance,

Section 7, pages 1 8-1 9 (1 999 revision) standard for milk (sometimes

referred to herein after as "ESL" milk) or (b) it is aseptically packaged and

does not require refrigeration for storage at a temperature less than about

85°F, sometimes referred to hereinafter as "aseptic" or aseptically

packaged" milk.

Another object of the invention is to provide a packaged

concentrated milk product for use in currently available dispensing

machines used for reconstituting and dispensing juices.

A further object is to provide a concentrated liquid milk

product package that produces substantial cost savings for export,

military uses such as for naval ships and submarines, and for commercial

and government food service programs.

Still another object of the invention is to provide milk

concentrate packages in standard retail pint and quart packages for the

general population that yield about V_ gallon for the pint and about one

gallon for the quart when reconstituted. In general, concentrate packages

having from about 2 to 64 ounces are provided for use.

A still further object of the invention is to provide milk

concentrate that is enriched with vitamins and other nutritive ingredients

that address special dietetic needs of special groups with dietary

restrictions. Another object is to provide a UHT pasteurized liquid milk

concentrate packaged in an amount of up to 300 gallons while gaining

shelf-life and economic benefits heretofore unknown in the dairy industry

and enabling the on-site destination reconstituting of the concentrate

using existing dispensing equipment and otherwise using uncomplicated,

simple water to milk concentrate mixing techniques in water to

concentrate volume ratios in the range of about 3: 1 to 4: 1 .

In one embodiment, the package comprises a container for

a preselected amount of the ultrapasteurized liquid milk concentrate with

a structural configuration effective for use with dispensing means which

includes means for mixing the ultrapasteurized milk concentrate with

water to create a reconstituted milk beverage that tastes like fresh milk.

To preferably produce a 1 % reconstituted product at a mix ratio of about

3 to 3.7 of water to concentrate, the ultrapasteurized milk concentrate

includes a high-solids condensed skim milk (HSCS) in the range of about

87.4% to about 89.4% by weight (more generally about 80% to about

90% by weight) a cream content in the range of from about 8.5% to

1 0.5% by weight, and a stabilizer content of about 0.7% by weight

(based on solids content of stabilizer) . To preferably produce a skim milk

product at a mix ratio of about 3.25 to 4 of water to concentrate, the

ultrapasteurized milk concentrate includes a high solids condensed skim

milk (HSCS) in the range of about 96.5% to about 99% by weight, a

cream content in the range of about 0 to about 2.5% by weight, and a stabilizer solids content of about 0.75 % by weight. To preferably

produce 2% and 3.25% resonstituted whole milk products at a mix ratio

of about 3 to 3.5 of water to concentrate, the ultrapasteurized milk

concentrate includes high solids condensed skim milk (HSCS) range of

about 67.5% by weight to about 81 % by weight, cream content in the

range of about 1 8% to 31 .5% by weight, and a stabilizer content of

about 0.6 to about 0.65% by weight. More broadly, in order to produce

a spectrum of products of no fat to full fat milk products, mix ratios of

about 3 to 4, the high solids condensed skim milk is in the range of about

67 to about 99% by weight, cream is in the range of from about 0 to

about 31 .5% by weight, and the stabilizer is in the range of about 0.6 to

0.75% by weight. The initially pasteurized condensed skim milk has a

total milk solids nonfat (MSNF) content of at least about 30% by weight

or more, preferably about 35% to 45% by weight, and cream has a milk

fat content of from about 36% to 45% by weight. The stabilizer solids

content preferably consists essentially of sodium hexametaphosphate in

the range of about 97.0%^ to 99.0% and carrageenan (kappa type) in the

range of about 1 .0% to 3.0%. Other stabilizers may be employed to

achieve the benefits of this invention in view of this detailed description.

In a specific embodiment, the milk concentrate package has a structural

configuration effective for disposition of a liquid dispensing means

including discharge nozzle means for mixing said ultrapasteurized concentrate with water to dispense the reconstituted liquid milk

beverage.

The method for producing the ultrapasteurized liquid milk

concentrate of the invention comprises heating a milk starting product to

an elevated pasteurizing temperature under reduced pressure for an

amount of time sufficient to evaporate liquid from the milk starting

product to form a pasteurized, high-solids intermediate liquid milk

concentrate. An amount of cream is mixed with the intermediate milk

concentrate to form a condensed liquid blend having a preselected

amount of fat content to produce the reconstituted milk beverage having

the desired taste characteristics.

A final liquid milk concentrate is produced by mixing a

sufficient amount of a stabilizer material with a predetermined amount of

the condensed liquid blend. The stabilizer material is effective to ensure

uniform distribution of and prohibit separation and settling of milk solids

in the ultrapasteurized liquid milk concentrate during storage. The

stabilizer material is effective to produce a protein complex for forming

a stable dispersion of colloidal constituents and to substantially uniformly

distribute the colloidal constituents in the final liquid milk concentrate.

The stabilizer material maintains the preselected pH of the final liquid milk

concentrate in the range of about 6 to 8 during the ultrapasteurizing step.

The stabilizer material is further effective for inhibiting thermal

coagulation of milk proteins at the preselected pH of the final milk concentrated. The total MSNF content in the final liquid milk concentrate

is at least about 30% by weight of the concentrate to produce a

reconstituted milk beverage having a MSNF content of at least about

8.25% by weight.

The final liquid milk concentrate is ultrapasteurized to form

the ultrapasteurized liquid milk concentrate of the invention. The final

homogenizing and packaging of the ultrapasteurized milk concentrate

forms the ultrapasteurized liquid milk concentrate package of the

invention for subsequent mixing of the ultrapasteurized milk with water

to form the desired reconstituted milk beverage.

A feature of the invention is directed to a heating step that

includes foreheating the initial liquid milk to an elevated foreheating

temperature for a selected time period to produce the milk starting

product, which is then heated to the elevated pasteurizing temperature

that is higher than the foreheating temperature to produce the desired

intermediate liquid milk concentrate. When the initial liquid milk is a skim

milk, the elevated foreheating temperature is in a range of about 144°F

to about 1 52°F and the elevated pasteurizing temperature is maintained

in the range of about 1 78°F to 1 82°F for a time period in the range from

about 1 6-22 seconds to pasteurize the intermediate milk concentrate.

Another feature is directed to the manner of preparing the

stabilizer material for mixing with the condensed liquid blend. In a

specific embodiment, the stabilizer material is first solubilized in water under high shear conditions and at an elevated temperature to form a

stabilizer slurry that is mixed with the condensed liquid blend to form the

final liquid milk concentrate. In the preferred form, the stabilizer slurry

includes sodium hexametaphosphate and carrageenan so that when the

slurry is mixed with the condensed liquid blend, the carrageenan forms

a protein carrageenate complex with milk protein to provide the stable

dispersion of colloidal constituents. The sodium hexametaphosphate is

effective to aid in substantially uniformly distributing the colloidal

constituents and inhibiting thermal coagulation in the concentrate. The

stabilizer slurry includes a stabilizer material solids content in the range

of about about 33 to 35% by weight of the stabilizer slurry to produce

a stabilizer material solids content of less than about 1 .0% by weight of

the final liquid milk concentrate. The stabilizer material includes sodium

hexametaphosphate in the range of about 32 to 34.5% of the stabilizer

slurry and carrageenan (kappa type) in the range of about 0.3 to about

1 % by weight. Other stabilizers may be used as long as they provide the

benefits of this invention.

Another feature of the invention is directed to the particular

viscosity of the concentrates at different times during the processing.

The viscosity of the intermediate liquid milk concentrate is in the range

of about 300 to 400 centipoises at 40° to 45°F and the viscosity of the

ultrapasteurized (UHT) milk concentrate is in the range of about 1 ,000 to

1 ,500 centipoises at the same temperature range. The pasteurized intermediate liquid milk concentrate includes a milk solids nonfat (MSNF)

content preferably in the range of from 35.0% to 36.5% by weight up

to about 45% by weight. The pasteurized intermediate liquid milk

concentrate thus includes a MSNF content in an amount preferably of at

least about 35% to produce a reconstituted low fat milk product upon

mixing the ultrapasteurized milk concentrate with water. Moreover, the

upper limit of the milk solids nonfat content of about 45% precludes burn

damage of the final liquid milk concentrate during the ultrapasteurizing

step. Water is mixed with the ultrapasteurized milk concentrate to form

the reconstituted milk product in a water/concentrate volume ratio of

parts of water to parts of ultrapasteurized milk concentrate in the range

of about 3: 1 to about 4: 1 .

Another feature of the invention is directed to the

composition of the intermediate liquid milk concentrate that includes

intermediate high-solids milk concentrate in the range of from about 67%

to about 99% by weight, cream in the range of from about 0 to about

32% by weight, and stabilizer material in the amount of about 0.6 to

about 0.75% by weight of the concentrate. The reconstituted milk

beverage over the range of non fat to fat milk products includes a milk fat

content in the range of less than about 0.21 % to 3.25 % and a milk

solids nonfat content of at least about 8.25% by weight of the milk

beverage. A further feature of the invention is directed to the ultra

pasteurizing step that includes heating the intermediate liquid milk

concentrate to an elevated ultra pasteurizing temperature by direct

contact with steam for a period of time sufficient to form the

ultrapasteurized liquid milk concentrate. In particular, it has been found

that injecting steam directly into a continuous stream in flow of the

intermediate liquid milk concentrate at UHT conditions provides the

desired product of this invention. In a specific embodiment, the ultra

pasteurizing step includes heating the intermediate liquid milk concentrate

to a temperature in the range of about 288°F to 295°F for a period of

time sufficient to produce an ultrapasteurized liquid milk concentrate of

the invention. More specifically, the ultra pasteurizing heating step

includes first heating the intermediate liquid milk concentrate to a first

elevated temperature of about 1 80°F for a period from 30 to 36 seconds

and then directing the heated liquid milk concentrate to a direct steam

injection zone to be heated to about 290°F to 295°F for a period of

about 2 to 5 seconds.

The homogenizing step comprises homogenizing the

ultrapasteurized milk concentrate in the range of about 3000 psi to about

5000 psi. The packaging step for the ESL milk feature after

homogenizing includes the step of cooling the ultrapasteurized milk

concentrate to a temperature of less than about 45°F and filling

packaging means with the ultrapasteurized milk concentrate for disposition in a liquid beverage dispenser. In this packaging step, the

ultrapasteurized milk concentrate is disposed in a package for use in a

beverage dispenser that includes discharge nozzle means for mixing the

ultrapasteurized milk concentrate with water to form the desired

reconstituted milk beverage. For the aseptically packaged milk, it is at

temperatures of about 70°to 90°F, or about 80°F, during packaging. In

a further specific embodiment, the packaging step includes disposing up

to 300 gallons of the ultrapasteurized milk concentrate in a package

container.

In another embodiment of the invention, a preselected

amount of liquid skim milk is heated to a temperature in the range of

about 1 44° to 1 52°F for an amount of time sufficient to produce a

preheated milk starting product. The preheated milk starting product is

then pasteurized in the range of about 1 78°F to 1 82°F in a time period

in the range of about 1 6-22 seconds. The pasteurizing step is effected

under a vacuum to evaporate liquid from the milk starting product to

produce an intermediate condensed liquid milk including milk solids nonfat

in the range of about 35.0% to 36.5% by weight. Cream and stabilizing

material are mixed with the intermediate condensed liquid milk to produce

a final liquid milk concentrate including a cream content in the range of

8.5% to 1 0.5% by weight thereof and a stabilizing material content of

less than 1 .0% thereof. The final liquid milk concentrate is then

ultrapasteurized and homogenized to form the ultrapasteurized milk concentrate, which is then disposed in the package container for

subsequent reconstitution with water at a water/milk concentrate volume

ratio in the range from about 3: 1 to 4: 1 .

In another feature of the method of the invention, a liquid

milk starting product is heated under vacuum to an elevate temperature

for an amount of time sufficient to pasteurize the milk starting product

and evaporate liquid from the milk starting product to form a pasteurized,

high-solids condensed liquid skim milk including milk nonfat solids in the

range of about 35.0% to 36.5%. An amount of cream is mixed with the

pasteurized condensed skim milk to form a final skim milk concentrate.

The stabilizer slurry contains sodium hexametaphosphate and carrageenan

(kappa type) in amounts sufficient to prohibit separation, settling, and

crystallization of milk constituents in the final liquid milk concentrate

during storage. The final liquid skim milk concentrate is ultrapasteurized,

homogenized and packaged to form an ultrapasteurized milk concentrate

package for disposing in a liquid dispensing means including discharge

nozzle means for mixing the ultrapasteurized milk concentrate with water

to dispense a reconstituted milk beverage.

PROCEDURES AND OPERATING EXAMPLES

The ultrapasteurized concentrated milk product of the

invention is produced using a direct steam injection process to achieve

new and unexpected results. As will be described in more detail

hereinafter, the process of the invention is effected using a UHT direct steam injection apparatus as used in the dairy industry. For example, one

type of such apparatus used for ultrapasteurization is the direct heating

plant in which high pressure potable steam is mixed with the liquid milk

product by injecting the steam into the liquid milk product. More

specifically, a Tetra Pak VTIS direct steam injection system for UHT

pasteurization is used, as described hereinafter. See Tetra Therm Aseptic

VTIS Direct UHT treatment module based on steam injection, ^®1 996,

Tetra Pak Processing Systems AB, Lund, Sweden. The water added to

the liquid milk product is then removed by evaporation, usually under

reduced pressure, which also cools the product. The direct steam

injection apparatus provides a continuous ultrapasteurization process.

In a specific embodiment of the invention, the

ultrapasteurized milk concentrate is produced in a series of process steps.

First, a high solids condensed skim milk (HSCS) is prepared by

pasteurizing under vacuum conditions. HSCS and cream are mixed to

form about 1 ,000 to 4000 gallons in a batch tank of a condensed liquid

blend having a preselected fat content. A special stabilizer mixture is

mixed with warm water under high shear mixing conditions to form a

unique stabilizer slurry which is added to the condensed liquid blend to

ensure production of a final liquid milk concentrate that will provide a

reconstituted milk beverage having the desired taste and milk

characteristics. Vitamin A Palmitate and Vitamin D3 are added to the

batch, which is then ultrapasteurized and homogenized. The resultant ultrapasteurized milk concentrate is then held in sterile tanks until

packaging in an aseptic filler. The ESL milk concentrate of the invention

has a refrigerated shelf-life of below about 45°F for at least about 30

days or preferably about 4 months. The aseptic milk concentrate has a

shelf life of at least about 30 days, or preferably about 4 to 6 months,

when stored at a temperature of less than about 85°F. The HSCS milk

and cream are sources of milk-derived carbohydrates, proteins, and

minerals. In addition, the cream brings the desired milk fat content to the

UHT pasteurized milk concentrate of the invention.

The process parameters are controlled to maintain the milk

solids nonfat content in the HSCS within a critical range and the novel

stabilizer system under ultrapasteurization conditions to produce an

ultrapasteurized milk concentrate having substantially uniformly

distributed milk constituents of at least about 30% by weight MSFN,

preferably about 35 to about 45% by weight MSNF that do not separate.

And for the first time such a milk concentrate can be reconstituted with

water within an available juice or other beverage dispensing system to

yield a reconstituted milk product that has the same characteristics of and

tastes like fresh milk.

The starting pasteurized skim milk may be acquired in the

market place. Alternatively, the initial pasteurization process in a specific

embodiment of the invention is continuous and treats a skim milk (less

than 0.5% fat content) at a flow rate of 3000 gal/hr. The milk is first preheated for 10 minutes + /- 30 seconds at a temperature of about

1 50°F within a temperature range of 1 44°F to 1 52°F. The preheated

milk is then pasteurized at about 1 80° + /- 2°F for 1 6-22 seconds and

held for 1 0 minutes + /- 30 seconds under a vacuum of 23 + /-

0.5 inches of mercury with an air temperature of about 1 45°F. After

pasteurization, the HSCS is directed through a plate cooler for 3 minutes

at a flow rate of 800 to 1 ,000 gal/hr where it is cooled to a temperature

of less than 40°F.

Heating the milk under vacuum evaporates liquid and thus

produces the desired high solids intermediate condensed skim milk, which

includes preferably about 35.0 to 45.0% milk solids nonfat (MSNF), or

more, by weight as required for further processing. A lower MSNF

content of less than about 30% will not produce an ultrapasteurized milk

concentrate required to produce the novel milk beverage of the invention

when reconstituted with water. A higher MSNF greater than about 45%

may produce excessive viscosity of and "burn-on" in the final liquid milk

concentrate as it moves through the ultrapasteurizing equipment.

After the initial pasteurization, the intermediate HSCS milk

concentrate is mixed with cream having a fat content in the range of from

about 36% to about 45% to form a condensed liquid blend in a batch

tank having a capacity of at least 750 gallons. Stabilizer material is then

added to the batch of condensed liquid blend to form a final liquid milk

concentrate to be subsequently ultrapasteurized. The stabilizers are first mixed under high shear conditions with warm water having a temperature

of 95 + /- 5°F (90° to 1 00°F), preferably about 75°F ± 5°F. The

resultant stabilizer slurry includes a stabilizer content as stated above.

The initial stabilizer mixture composition used in forming the

slurry of the invention consists essentially of sodium hexametaphosphate

in the range of 97.0-99.0% and carrageenan (kappa type) in the range of

1 .0-3.0%. The stabilizer slurry is formed by metering the stabilizer

mixture and water into a high shear liquefier blender and mixing it for

about 1 5 minutes to get the stabilizer material into solution. If the

stabilizer is not solubilized, it will not be evenly distributed in the slurry

and as required in the final ultrapasteurized milk concentrate of the

invention. The desired amounts of Vitamins A Palmitate (250 ml) and D3

(1 00 ml) are added to the stabilizer slurry during the blending step. The

slurry mixture is then pumped into the batch tank and intermixed with the

condensed liquid blend of HSCS milk and cream. The viscosity of the

final liquid milk concentrate before ultrapasteurization is 300 to 400

centipoises at about 40° to 45°F. After UHT treatment, the viscosity of

the UHT milk concentrate is about 1 000 to 1 500 centipoises at about

40° to 45°F.

Four milk classifications exist in the industry as designated

by the government in terms of the percentage of the milk solids fat

content as Full Fat (3.25% Fat); Reduced Fat (2.00% Fat); Low Fat

(1 .00% Fat); and Fat Free (Skim,) ( < .21 % Fat). The composition of the final liquid milk concentrate of the invention varies depending on the

percentage of fat content desired in the reconstituted milk beverage. The

percentage of milk solids, nonfat in each final liquid milk concentrate is

at least about 30% to attain at least 8.25% milk solids nonfat content in

the reconstituted milk beverage made with the UHT milk concentrate of

the invention. The percentage of stabilizer solids in the milk concentrate

of the invention in each instance is less than one percent. The following

Table I shows the total solids calculated for the UHT pasteurized milk

concentrate of the invention based on the concentrate being reconstituted

with water in a water to concentrate volume ratio of 3 parts of water to

one part milk concentrate.

TABLE

The following Table II shows the percentage of fat, MSNF,

and total solids in reconstituted milk beverages with the characteristics

and tastes like any of the four types of fresh milk made by mixing water

with the liquid milk concentrate of Table I in a water to concentrate

volume ratio of 3: 1 . TABLE

A beverage dispenser manufactured by Wilshire bearing the

trademark QUANTUM 4000 operates with a plastic bag package

containing the liquid milk concentrate of the invention. A peristaltic pump

draws the concentrate from the package and discharges it through a

dispensing nozzle to mix it with water flowing at a rate effective to

reconstitute the concentrate at a mixing ratio of parts of water to parts

of concentrate in a volume ratio range of from about 3: 1 to about 4: 1 .

The reconstituted milk beverage has the characteristics of and tastes like

fresh milk.

In another specific embodiment, for example, the

concentrated milk is loaded into a 300 gallon tri-wall aseptic bag-in-box

using an INTASEPT bulk bag-in-box to connect to a steam sterilized

connector that pierces the exit port on the aseptic 300 gallons in the box.

This allows the concentrated milk to retain its aseptic atmosphere when

penetrated by the sterile connector. The concentrated sterile milk is then

unloaded into a sterile blending tank that holds a combination of 2,000 gallons of both sterile water and concentrated milk. The sterile

concentrated milk and water are mixed together in the blending tank at

the proper mix ratio to reconstitute the milk to regular strength milk. The

milk is still in a sterile atmosphere. The regular strength milk is then

pumped into a sterile surge holding tank until being pumped to a dairy

packaging machine where the product still remains in a sterile

atmosphere. It is then packaged in paper milk cartons.

The 300 gallon bag-in-box has at least a 30 day shelf life,

and more preferably at least 4 months, from the date of manufacturing.

The paper retail package would have the remaining shelf life of at least

about the 90 days minus the time from date of manufacturing to the date

the 300 gallon bag-in-box is processed for retail packaging. Since the

concentrated aseptic milk has remained in a USDA approved aseptic

system, the product does not have to be re-pasteurized. As a new and

unexpected result, this system allows for a dairy to be established

anywhere in the world that local laws permit at a minimum expenditure

compared to regular dairies.

Another embodiment of this process to produce an aseptic

shelf stable UHT milk concentrate of the invention starts with a liquid

milk concentrate having a nonfat milk solids content in the range of from

about 30% to about 45% by weight with an optimum content range of

about 36% to 40% by weight to ultimately produce a reconstituted milk

beverage by mixing about 3 to 4 parts water to one part of the UHT milk concentrate. The industry-wide fat content classification of the different

types of milk is from less than 0.21 % up to 3.25% by weight of

butterfat thus including fat free ( < .21 % fat content) milk, low fat ( 1 %

fat content) skim, reduced fat (2% fat content) milk and full fat (3.25%

fat content) milk. So, depending on the particular classification desired

in the reconstituted milk beverage of the invention, a sufficient amount

of cream may be mixed with the starting liquid milk concentrate to

provide a condensed liquid milk blend having a sufficient amount of fat

content effective to form a reconstituted milk beverage having a fat

content of from less than 0.21 % up to 3.25% by weight of the

reconstituted milk beverage when the ultrapasteurized liquid milk

concentrate is reconstituted with water. If a no fat product is desired, no

cream or fat is needed in the mixture. The following Examples 1 -5

further illustrate the practice of the invention. Vitamin A and D

concentrate is added in a minor amount to the ingredients.

EXAMPLE 1

Skim white Milk (mix ratio 4. Ox)

EXAMPLE 2

1 % White Milk (mix ratio 3.7x)

EXAMPLE 3

2% White Milk (mix ratio 3.25x)

EXAMPLE 4

Whole White Milk (mix ratio 3. Ox)

In the Examples 1 -5, a stabilizer is first prepared for adding

to the liquid milk concentrate to form the condensed liquid milk blend that

is to be ultrapasteurized. In these examples, one (1 ) pound of stabilizer

consisting of sodium hexametaphosphate and carrageenan (kappa type)

is mixed with two (2) pounds of warm water (70° F minimum). The

resultant mixture is then blended together in a high shear blender for 1 5

minutes to form a stabilizer slurry, which is then mixed with the initial

liquid milk concentrate for at least 15 minutes to produce the condensed

liquid milk blend that is to be UHT pasteurized. The stabilizer in the

examples is a slurry in water of about 1 -2% of the total weight of the

condensed liquid milk blend which may include cream, flavor, juice

concentrate, sweetener, etc. Up to about 10% by weight of the UHT

milk concentrate product may contain a flavor, sweetening agent or juice

concentrate. In the case of these products the fresh milk taste still

dominates the product upon reconstitution with a flavored, sweetened or juice note added to the product. Such flavors or sweetening agents are

selected from the group consisting of caramel, vanilla, hazelnut, cocoa,

coffee extract, peach, strawberry, chai tea, vanilla chai, sucralose,

aspartame, corn syrup and fructose. Fruit or juice concentrates are

selected from the group consisting of peach, orange, strawberry and

grape.

The condensed liquid milk blend, with stabilizer and other

ingredients, of Examples 1 -5 is then continuously run through a Tetra Pak

VTIS direct steam injection UHT pasteurization system that uses a

prewarming step of about 1 80°F for about 30-36 seconds and then heats

the milk to a temperature range of from about 288°F to about 294°F for

2.5 to 5 seconds. In these examples, the ultrapasteurizing temperature

is about 294°F. The UHT milk concentrate is then sent to a cooling

condenser, which cools the concentrate to a temperature of from about

80°F to 90°F within about 2 to 5 seconds. The UHT milk concentrate

is then run through a high-pressure homogenizer, preferably at about

3500 to 5000 psi, or as low as 1 500 psi and sent to an aseptic bag filler

machine that sterilizes the bag with steam before it is filled with the

sterilized UHT milk concentrate. The nozzle and inside lip of the bag is

sprayed with H₂O₂. The final product is checked for proper milk solids

and fat content as well as the proper pH level of about 6-8. The milk

concentrate of these examples includes a total milk solids content of from about 40% to about 46% by weight when it is running through the direct

steam injection system, homogenizer, and cooling condenser.

The milk products of Examples 1 -5, after dilution with water

at the mix ratios, when tested for sensory characteristics by consumers,

all satisfy the requirements of a fresh milk product. The UHT milk

concentrate and the reconstituted product do not exhibit any visible

separation or coagulation or change in color. The aroma and taste satisfy

the further characteristics of fresh milk without the negative attributes of

"cooked", "scorched", "burnt", etc., as described above. Furthermore,

the products have the texture and mouth feel of fresh milk without the

defects for milk products which may be described as watery, thin,

coagulated, sandy, gritty or separated.

While the ULTRA-HIGH TEMPERATURE MILK

CONCENTRATE, PACKAGE, DISPENSER AND METHOD OF PRODUCING

SAME have been shown and described in detail, it is obvious that this

invention is not to be considered as limited to the exact form disclosed,

and that changes in detail and construction may be made therein within

the scope of the invention without departing from the spirit thereof.

WHAT IS CLAIMED IS:

Claims

1 . An ultra-high temperature pasteurized liquid (UHT) milk

concentrate for mixing with water to provide a reconstituted milk

beverage that tastes like fresh milk having a flavored, sweetened

or juice note comprising

an ultra-high temperature pasteurized liquid (UHT) milk

concentrate which is produced by directly injecting steam into a

condensed liquid milk blend containing a flavor, sweetening or juice

concentrate, said UHT milk concentrate having a nonfat milk solids

content of at least 30% by weight and containing a stabilizer in an

effective amount to provide

(a) an extended shelf stability of at least 30 days without

granulation and/or separation of the milk solids,

(b) milk solids which do not separate upon dilution with

water, and

(c) upon dilution with water provides a drinkable product

having a fresh milk taste which dominates the product with a flavored,

sweetened or juice note.

2. The UHT milk concentrate of claim 1 where the flavor or

sweetening agent is selected from the group consisting of caramel,

vanilla, hazelnut, cocoa, chocolate, coffee extract, peach, strawberry,

chai tea, vanilla chai, sucralose, aspartame, corn syrup, and fructose.

3. The UHT milk concentrate of claim 1 containing a juice

concentrate from the group consisting of peach, orange, strawberry,

coffee extract, and grape.

4. The UHT milk concentrate of claims 1 or 3 wherein the

flavor, sweetening agent or juice concentrate is contained in an amount

up to 1 0% by weight of the drinkable product.

5. The UHT milk concentrate of claim 1 which is diluted with

water at a ratio of about 3: 1 to about 4: 1 of water to concentrate.

6. The UHT milk concentrate of claim 1 wherein said stabilizer

consists essentially of sodium hexametaphosphate and carrageenan.

7. The UHT milk concentrate of claim 1 wherein said nonfat

milk solids content is from about 35% to about 46% by weight.

8. The UHT milk concentrate of claim 1 having a pH in the

range of about 6 to 8.

9. The UHT milk concentrate of claim 1 wherein said nonfat

milk solids (MSNF) content is in an amount to produce a drinkable

product having an MSNF of at least about 8.25% by weight.

10. The UHT milk concentrate of claim 1 wherein said nonfat

milk solids (MSNF) content is from about 35% to about 45 % by weight

and said concentrate has a milk fat content of less than about 0.74% to

about 1 1 .77% by weight.

1 1 . The UHT milk concentrate of claim 1 wherein said stability

is achieved at a refrigeration temperature of less than about 45°F.

1 2 The UHT milk concentrate of claim 1 wherein said stability

is achieved by aseptic packaging of said concentrate for storage.

1 3. The UHT milk concentrate of claim 10 wherein said stability

is for a term of at least four months.

1 4. An aseptic package of an ultra-high temperature pasteurized

liquid (UHT) milk concentrate for mixing with water to provide a

reconstituted milk beverage that tastes like fresh milk having a flavored,

sweetened or juice note comprising

a container for holding under aseptic conditions an ultra-high

temperature pasteurized liquid (UHT) milk concentrate which is produced

by directly injecting steam into a condensed liquid milk blend containing

a flavor, sweetening or juice concentrate, said UHT milk concentrate having a nonfat milk solids content of at least 30% by weight and

containing a stabilizer in an effective amount to provide

(a) an extended shelf stability of at least 30 days without

granulation and/or separation of the milk solids,

(b) milk solids which do not separate upon dilution with

water, and

(c) upon dilution with water provides a drinkable product

having a fresh milk taste which dominates the product with a flavored,

sweetened or juice note,

said container for delivering the UHT milk concentrate for

mixing with water to form the drinkable product.

1 5. The aseptic package of the UHT milk concentrate of claim

1 4 where the flavor or sweetening agent is selected from the group

consisting of caramel, vanilla, hazelnut, cocoa, chocolate, coffee extract,

peach, strawberry, chai tea, vanilla chai, sucralose, aspartame, corn

syrup, and fructose.

1 6. The aseptic package of the UHT milk concentrate of claim

1 4 containing a juice concentrate from the group consisting of peach,

orange, strawberry, coffee extract, and grape.

1 7. The aseptic package of the UHT milk concentrate of

claim 14 wherein said stabilizer consists essentially of sodium

hexametaphosphate and carrageenan.

1 8. The aseptic package of the UHT milk concentrate of

claim 14 wherein said nonfat milk solids content is from about 35 to

about 46% by weight.

1 9. The aseptic package of the UHT milk concentrate of

claim 1 4 wherein said nonfat milk solids (MSNF) content is in an amount

to produce a drinkable product having an MSNF of at least about 8.25%

by weight.

20. A beverage dispenser for delivery of an ultra-high

temperature pasteurized liquid (UHT) milk concentrate and mixing with

water to provide a reconstituted milk beverage that tastes like fresh milk

having a flavored, sweetened or juice note comprising

a container containing an ultra-high temperature pasteurized

liquid (UHT) milk concentrate which is produced by directly injecting

steam into a condensed liquid milk blend containing a flavor, sweetening

or juice concentrate, said UHT milk concentrate having a nonfat milk

solids content of at least 30% by weight and containing a stabilizer in an

effective amount to provide (a) an extended shelf stability of at least 30 days without

granulation and/or separation of the milk solids,

(b) milk solids which do not separate upon dilution with

water, and

(c) upon dilution with water provides a drinkable product

having a fresh milk taste which dominates the product with a flavored,

sweetened or juice note,

said container for delivering the UHT milk concentrate for

mixing with water and

a dispenser having a source of water and a mixer for mixing

the water with the UHT milk concentrate from said container to form and

deliver the drinkable product which has the characteristics of and tastes

like regular fresh milk having a flavored, juice or sweetened note.

21 . The beverage dispenser of claim 20 wherein said mixer is

configured to dispense the UHT milk concentrate with water at a ratio of

about 3: 1 to about 4: 1 of water to concentrate.

22. The beverage dispenser of claim 20 wherein said nonfat milk

solids (MSNF) content is from about 35% to about 46% by weight and

said concentrate has a milk fat content of less than about 0.74% to

about 1 1 .77% by weight.

23. A method for producing an ultra-high temperature

pasteurized liquid (UHT) milk concentrate for mixing with water to provide

a reconstituted milk beverage that tastes like fresh milk having a flavored,

sweetened or juice note comprising

providing a condensed liquid milk blend containing a

stabilizer and a pasteurized liquid milk concentrate containing a flavor,

sweetening or juice concentrate having an amount of nonfat milk solids

sufficient to produce the UHT milk concentrate having a nonfat milk

solids content of at least 30% by weight when said UHT milk

concentrate is reconstituted with water,

said stabilizer being present in an effective amount to form

a stable dispersion of said milk solids,

directing a continuous flow of said stabilized condensed

liquid milk blend into direct contact with steam by injecting steam directly

into said flow of condensed liquid milk blend at an effective ultra-high

pasteurizing temperature for a time sufficient to form said UHT milk

concentrate having a nonfat milk solids content of at least 30% by

weight with

(a) an extended shelf stability of at least 30 days without

granulation and/or separation of the milk solids,

(b) milk solids which do not separate upon dilution with

water, and (c) upon dilution provides a drinkable product having a

fresh milk taste which dominates the product with a flavored, sweetened

or juice note.

24. The method as defined in claim 22 wherein said continuous

flow directing step includes heating said condensed liquid milk blend in

direct contact with said injected steam at a temperature in the range of

about 288°F to about 294°F for a period of time sufficient to produce

said UHT milk concentrate.

25. The method as defined in claim 22 wherein said continuous

flow directing step includes first heating said condensed liquid milk blend

to a first temperature of about 1 80°F for a period of from about 30 to

about 36 seconds, and then

directing the heated condensed liquid milk blend into direct

contact with said injected steam at a temperature of about 290°F to

about 294°F for a period of about 2 to about 5 seconds to form said UHT

milk concentrate.

26. The method as defined in claim 22 wherein the viscosity of

the condensed liquid milk blend is in the range of 300 to 400 centipoises

at about 40° to about 45°F, and the viscosity of the UHT milk concentrate is in the range of

1 000 to 1 500 centipoises at about 40° to about 45°F.

27. The method as defined in claim 22 wherein said stabilizer is

effective to maintain a preselected pH of said condensed liquid milk blend

in the range of about 6 to 8.

28. The method as defined in claim 22 wherein said stabilizer in

said condensed liquid milk blend includes sodium hexametaphosphate and

carrageenan.

29. The method as defined in claim 22 wherein said stabilizer

slurry includes a sufficient amount of stabilizer to produce said condensed

liquid milk blend having a stabilizer content of less than about 1 .0% by

weight.

30. The method as defined in claim 22 further including the

steps of homogenizing said UHT milk concentrate, and then

packaging said homogenized UHT milk concentrate for

subsequent mixing with water to form said reconstituted milk beverage.

31 . The method as defined in claim 22 wherein said condensed

liquid milk blend includes a sufficient amount of cream to provide a sufficient amount of fat content effective to form a reconstituted milk

beverage having a fat content of from less than 0.21 % up to 3.25% by

weight of said milk beverage when said UHT milk concentrate is

reconstituted with water.

32. A package of an ultra-high temperature pasteurized liquid

(UHT) milk concentrate for mixing with water to provide a reconstituted

milk beverage that tastes like fresh milk having a flavored, sweetened

or juice note comprising

a container for holding an ultra-high temperature pasteurized

liquid (UHT) milk concentrate which is produced by directly injecting

steam into a condensed liquid milk blend containing a flavor, sweetening

or juice concentrate, said concentrate having a nonfat milk solids content

of at least 30% by weight and containing a stabilizer in an effective

amount to provide

(a) an extended shelf stability of at least 30 days without

granulation and/or separation of the milk solids,

(b) milk solids which do not separate upon dilution with

water, and

(c) upon dilution with water provides a drinkable product

having a fresh milk taste which dominates the product with a flavored,

sweetened or juice note.

33. The package as defined in claim 32 wherein said UHT milk

concentrate includes a condensed skim milk having nonfat milk solids of

about 35% to 45% by weight, said skim milk in the range of about 87

to 90% by weight, a cream content in the range of up to 8.5% to 10.5%

by weight, and a stabilizer content of less than about 1 % by weight.

34. The package as defined in claim 32 wherein said milk

concentrate container has a structural configuration effective for

disposition in a liquid dispenser including a discharge nozzle for mixing

said ultrapasteurized milk concentrate with water to dispense said

reconstituted liquid milk beverage.