HK1090518A - Production of protein composition from a dairy stream and its use as an ingredient in the manufacture of a cheese - Google Patents

Description

Protein composition prepared from dairy stream and its use as a component in cheese making

Background

Technical Field

The present invention relates to a process for the preparation of a milk component. More particularly, the invention relates to protein compositions prepared from dairy streams and their use in cheese making.

Description of related Art

Granular or powdered protein concentrates, as well as milk retentate powders, are widely used as components in the food industry, especially in the manufacture of cheese and processed cheese. When expressed on a moisture or fat free basis, these components can be more generally expressed as proteinates typically having > 50% protein, usually > 70% protein and sometimes > 80% protein.

U.S. Pat. nos. 6,183,804 and 6,183,805 teach methods of preparing powdered milk protein concentrate fractions using ultrafiltration and diafiltration (diafiltration) followed by concentration and drying. This method provides only limited means to manipulate the mineral content of the product and ignores the methods of altering the properties of the casein and whey proteins, respectively. These components are commonly referred to as MPCs. Although these protein concentrates are generally useful in the production of processed cheese, there are also some limitations. Because the required ultrafiltration and diafiltration stages increase disproportionately as the protein content increases, the production of higher protein concentration fractions can also be disproportionately expensive compared to ultrafiltration. While the lower protein concentration component has a higher lactose and mineral concentration. An excess of lactose in the final product (cheese) can lead to browning and flavor loss, as well as a chance of unwanted secondary fermentation and lactose crystallization due to the limited amount of water present. Therefore, most cheese and processed cheese manufacturers prefer a protein concentrate component with a concentration of greater than 70% protein.

By manipulating the monovalent and divalent cations, the functional properties of the proteinate, such as solubility and casein-making properties, can be improved. Well known methods for manipulating cations in protein concentrates are, for example, pH adjustment or salt addition during ultrafiltration (U.S. patent No. 5,356,639). A broader range of such cation and protein content manipulation and control is taught in international publication No. WO 01/41579, wherein the proteinate component may be prepared by a combination of ultrafiltration, diafiltration, and cation exchange using a cation exchange resin medium. The limitation of this approach is that the exchange of monovalent cation for divalent cation in the process product of the treatment is subject to stoichiometric control, i.e., two moles of monovalent ion for each mole of divalent ion. As a result, higher levels of sodium and potassium ions in the product can impair its flavor and cause problems with food labeling, especially in low salt dietary formulations.

U.S. patent No. 4,202,907 teaches another method for the preparation of proteinates. Ion exchange of skim milk with sodium ions is first performed to replace part of the calcium ions, and then rennin modifies the properties of the protein. The treated solution is then converted to a dry proteinate component by concentration and drying. This method also has the above-mentioned limitations of stoichiometric substitution of monovalent and divalent cations. In an alternative embodiment, pockels (pearch) describes a method (low cost) of preparing a proteinate by dissolving casein in a monovalent alkaline salt solution (NaOH) using whey as a solvent, and then treating the solution with rennet. The treated solution was then ion exchanged to remove calcium, concentrated and dried. The process provides a range of stoichiometrically operating on cations, and certain ranges of ratios of operating protein to lactose, or casein to whey protein + lactose concentrations. However, this method does not teach how to get rid of the stoichiometric substitution limitation, nor does it teach a method to modify the properties of the casein and whey proteins, respectively.

Coprecipitates are another proteinate known. The method generally involves heating skimmed milk at 85-95 deg.C for 1-20 minutes, and adding CaCl₂And/or acid treatment to precipitate the protein. The recovered protein concentrate can be dissolved by treatment with NaOH and dried (Dairy handbook 2 nd revised edition, Lele processing systems, Lande, Sweden, 2003, page 414-^ndtransPak processing System, Lund, Sweden, 2003 pp.414-415)). Different processing modes may allow for multiple monovalent-divalent cation ratios. Due to the heat treatment of the proteins, it is hardly possible or impossible in the art to manipulate the properties of the casein and whey proteins separately.

It is an object of the present invention to go forward towards overcoming these disadvantages, or at least to provide the public with a useful choice.

Summary of The Invention

Accordingly, the present invention provides in one aspect a method of producing a protein composition from a milk stream, comprising the steps of:

a) subjecting the milk stream to conditions which result in the formation of a protein concentrate and a serum;

b) separating the protein concentrate from the serum;

c) dissolving the separated protein concentrate in an aqueous solution;

d) combining the solubilized protein concentrate with the separated whey to form the protein composition; and

e) concentrating the protein composition formed in step d).

In one embodiment, the conditions of step a) comprise adjusting the pH of the milk stream to 4.5-4.8, followed by heating to form the protein concentrate and the whey.

In another embodiment, the conditions of step a) comprise adding to said milk stream an enzyme capable of converting kappa (kappa) -casein to para (para) -kappa-casein, followed by heating to form a protein concentrate and a serum.

In another embodiment, step a) comprises dividing the aqueous medium of the milk stream containing the milk proteins into two parts,

adjusting the pH of a part of the mixture to 4.5-4.8,

adding to the other part an enzyme capable of converting kappa-casein to para-kappa-casein, and

the two fractions are combined and the combined stream is heated to form a protein concentrate and a serum.

In one embodiment, the dairy stream is skim milk.

In another embodiment, the milk stream is pasteurized.

In another embodiment, the milk stream is subjected to a membrane concentration step.

In another embodiment, the membrane concentration step is an ultrafiltration step.

In one embodiment, the pH in step a) is adjusted by adding an acid, preferably a food approved acid, more preferably hydrochloric acid or sulfuric acid.

In one embodiment, when the milk stream contains lactose, the pH of the lactose is adjusted by fermenting a portion of it to acid, most commonly lactic acid, by adding a starter culture.

In one embodiment, the starter culture is any food-approved bacterial culture capable of fermenting lactose to form acids.

In one embodiment, the bacterial culture is a strain of lactobacillus.

In one embodiment, the pH is adjusted to 4.6.

In one embodiment, the milk stream is split and the further milk stream is reacted with the kappa casein converting enzyme at a temperature below about 15 ℃, more preferably below 10 ℃.

In another embodiment, the kappa casein converting enzyme is chymosin (chymosin).

In another embodiment, the kappa casein converting enzyme is rennet, preferably derived from an animal or microbial source.

In another embodiment, the protein concentrate and serum are formed by heating to a temperature of about 25 ℃ to 70 ℃, more preferably 30 ℃ to 55 ℃, and most preferably 40 ℃ to 50 ℃.

In one embodiment, the heating is done at a holding time of 1 to 600 seconds, preferably 5 to 200 seconds, more preferably 10 to 50 seconds.

In another embodiment, the protein concentrate isolated from step b) is washed with water.

In another embodiment, the protein concentrate isolated from step b) is milled.

In another embodiment, in step c), the protein concentrate is dissolved in an alkaline solution.

In another embodiment, the alkali solution contains cations including sodium, potassium, calcium, magnesium, or mixtures thereof.

In another embodiment, the protein level of the serum isolated in step b) is adjusted by adding, removing or modifying said protein.

In another embodiment, the whey separated in step b) is concentrated before being combined with the solubilized protein concentrate in step d).

In another embodiment, the whey separated in step b) is further separated into a protein-rich stream and a lactose-rich stream.

In another embodiment, the concentrated protein solution is mixed with all or a portion of the protein-enriched whey stream and all or a portion of the lactose-enriched stream in step d) to form the protein composition.

In another embodiment, fat, oil or cream is added to the protein composition formed in step d).

In another embodiment, the protein composition is homogenized.

In another embodiment, the protein composition is dried.

In another embodiment, the protein composition is used for making cheese.

The invention also includes protein compositions prepared by the above-described methods.

In another embodiment of the invention, cheese is prepared using a composition as defined above.

In another embodiment the invention relates to a milk proteinate composition containing para-kappa-casein and whey protein, which milk proteinate composition does not form a gel when concentrated.

In one embodiment, the proteinate composition has a calcium concentration of 2,700mg/kg to 15,000mg/kg and a sodium concentration of 11,000mg/kg to 1,300 mg/kg.

In another embodiment, the milk protein salt composition is a powder.

In another embodiment of the invention, the cheese is prepared using a proteinate composition as defined above.

The invention may be said to consist of the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features; where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

Brief description of the drawings

FIG. 1 shows a flow diagram of a method according to an embodiment of the invention.

Description of The Preferred Embodiment

As used herein, a "dairy stream" may comprise any liquid source of milk protein. Although the most common type of dairy stream used in the present invention is skim milk, the dairy stream may comprise Milk Protein Concentrate (MPC) as a concentrate or in a reconstituted or suspended form.

In this context, "skim milk" means milk having a low fat content, preferably less than 1% by weight. Such milk may also be referred to in the art as "low fat milk".

Herein, "whey" refers to the supernatant remaining after casein precipitation. The serum comprises the supernatant and the proteins dissolved or suspended therein.

Detailed description of the drawings

The following is an embodiment of the present invention shown in fig. 1.

Skimmed milk can be separated from whole milk, reconstituted whole milk, or reconstituted skimmed milk from skimmed milk powder. Preferably the skim milk is pasteurized.

Alternatively, the skim milk is concentrated using membrane technology to enrich the retentate in protein. The preferred membrane technique is ultrafiltration. The protein concentrate may be 20-80% by volume of the raw skim milk.

Alternatively, the skim milk or protein concentrate is treated with an enzyme that converts kappa-casein to para-casein. The preferred enzyme reaction temperature is below 15 ℃.

In the process shown in fig. 1, the skim milk or protein concentrate (milk) stream is divided into two portions and treated under different conditions. The two portions are then combined and heated to form a protein concentrate as described below.

In an option, which is not shown in the figure, the milk stream need not be split, either the starter culture or the acid post-heat treatment can be added; or adding enzyme and heating.

In the embodiment shown, acid is added to the skim milk or protein concentrate to a pH of about 4.6 in the left half, so that upon heating, the insoluble protein rapidly precipitates. The precipitated protein and whey are in a state of relatively easy separation. Preferred separation methods tend to sieve (screen) and decant (decanter) or a combination of both.

In the right half, an enzyme is added. Chymosin (rennet) is a preferred enzyme. The acidity can be provided by mixing with a dilute acid, such as sulfuric acid or hydrochloric acid, or alternatively, by adding a suitable bacterial starter culture to produce the acid by fermenting lactose present in the solution.

The left and right half run products were then combined. It is heated to a preferred temperature range, for example 25 ℃ to 70 ℃, for 1 to 600 seconds, preferably 5 to 200 seconds. Any range within this limit may be used. The most preferred temperature is 30 ℃ to 55 ℃ and the holding time is 10 to 50 seconds.

Alternatively, the recovered insoluble protein concentrate may be washed with water, or in a preferred embodiment, the insoluble protein is ground to a finer, relatively uniform particle size. More preferably, the clot grinding is performed using a colloid mill.

The insoluble protein concentrate is then dissolved in a solution containing a mixture of monovalent and divalent cations. Preferred monovalent cations are sodium and potassium ions, preferred divalent cations are calcium and magnesium ions, and preferred delivery vehicles for the different ions are hydroxides or oxides thereof. The ratio of monovalent to divalent cations used is the desired ratio of ion pairs in the final product (component). In a preferred embodiment, the monovalent cation is 20% to 90% and the divalent cation in balance therewith (80% to 10%).

In an alternative embodiment, the solubilized protein concentrate may be treated with an enzyme. Preferred enzymes are those that convert kappa-casein to para-kappa-casein. The enzyme may be inactivated after sufficient heat treatment.

Such as would include whey protein, lactose and various salts as well as minor ingredients.

The properties of the serum can be purified, enhanced or modified by treating the serum using a number of methods. Preferred techniques that may be used are, but are not limited to, ultrafiltration, electrodialysis, ion exchange and affinity chromatography, mineral and/or pH adjustment, heat treatment, shearing and concentration.

In another aspect, the serum may be separated into two or more sub-streams. One product of the process may be enriched in protein, while the other is enriched in lactose. Each of the products of the schemes can be processed by the preferred techniques identified above.

The solubilized protein concentrate stream is then combined with all or a portion of the protein-enriched stream and all or a portion of the lactose-enriched stream derived from all or a portion of the processing of the whey. In a preferred embodiment, the mixing ratio is determined by the desired ratio of casein, whey protein and lactose in the final product. In a preferred embodiment, the protein content (expressed in dry weight) of the desired mixture is at least higher than 40% and lower than 90%.

Alternatively, edible oils, fats and milk fats, creams or higher creams may be added to the mixed process product.

Alternatively, the combined process product may be homogenized to provide a fat-containing phase having a fine uniform dispersion in the aqueous phase.

Preferably the mixture is a concentrate. The preferred concentration device is a multi-stage evaporator.

Alternatively, the components may be added after concentration and before drying.

Optionally, the pH and/or temperature may be adjusted to optimize the viscosity of the solution prior to drying.

After concentration, the product was dried. The preferred drying equipment is spray drying. Preferably, the moisture in the product leaving the dryer is above 0.5% and below 10% by weight.

After packaging, the product can be stored and used as a component at the desired time and place.

Said components, which are rich in active milk proteins and have a higher nutrition, are particularly suitable for the production of cheese-like products, more preferably for the production of processed cheese-like products. The properties of the components can be tailored to these applications, which other techniques known in the art are not effective to achieve.

In a preferred embodiment, the ingredients are used in the manufacture of processed cheese by adding a drinkable solvent (preferably water), milk fat, salt, dissolved salts and flavourings. The mixture is heated with shear (cooking) and once a molten homogeneous mass is formed, it is packaged into a processed cheese or processed cheese-like product.

The invention has the use of the produced protein composition as a component for the production of further components or consumer products. The levels of the ingredients may be adjusted as required during the manufacture of the composition and the levels of these ingredients may be "maintained" to the final product.

Examples

EXAMPLE 1 preparation of samples of the Components

Curd 1

From the serum acidified with dilute sulphuric acid to ph4.6, 3000L of casein in skim milk was separated and the excess serum was drained off yielding 180kg of wet milk protein. The wet milk protein is not washed. It is referred to as "protein concentrate 1".

Curd 2

1500L of skim milk was reacted with rennet ("Australian double vigor", using 1 part rennet to 10,000 skim milk) at 10 ℃. On the following day, the casein was isolated from the serum by acidification to ph4.6 with dilute sulphuric acid. The excess milk was then drained to yield 90kg of wet milk protein. The wet milk protein is not washed. It is referred to as "protein concentrate 2".

TABLE 1 composition of the components

	Skimmed milk	WPC(Alacen 392TM)
			Protein (TN)*×6.38)％	3.93
True protein%		75.9
			Water content%	90.56	4.2
Ash content%		3.44
			Fat%		5.33
Lactose%		7.18
			Ca(mg/kg)	1310

^*TN ═ Total Nitrogen in the tables and tables

Example 2 preparation of whey protein solution

17.2kg of Whey Protein Concentrate (WPC) (trade name Alacen 392)^TMMarketed by the Fantala corporation, Inc. (Fonterra Co-operating Group Limited), Oakland) dissolved in 260kg of demineralized water to make a 6% WPC solution (containing native (undenatured) whey protein). Half of the whey protein solution was heated to 115 ℃ for 4 minutes by circulating in an evaporator pre-heat holding tube, denaturing the protein.

EXAMPLE 3 preparation of soluble mineralized protein salt solution

Run 1

30kg of protein concentrate 1 from example 1 were mixed with 70L of the native whey protein solution from example 2. The mixture was treated with sodium hydroxide (0.2 kg NaOH dissolved in about 100L water) with stirring at 65 ℃. Once the pH of the mixture stabilized at 6.8, the solution was dried to produce a powdered protein salt composition.

Run 2

30kg of the protein of example 1Concentrate 1 was mixed with 70L of the native whey protein solution of example 2. Stirring at 65 deg.C with calcium hydroxide (0.3 kg Ca (OH)₂) Dissolved in about 100L of water). Once the pH of the mixture stabilized at 6.9, the solution was dried to produce a powdered protein salt composition.

Run 3

30kg of protein concentrate 2 from example 1 was mixed with 70L of denatured whey protein solution from example 2. The mixture was treated with sodium hydroxide (0.2 kg NaOH dissolved in about 100L water) with stirring at 65 ℃. Once the pH of the mixture stabilized at 6.8, the solution was dried to produce a powdered protein salt composition.

EXAMPLE 4 preparation of Dry powder

The proteinate from cases 1, 2 and 3 of example 3 was spray dried using a single stage dryer with an inlet temperature of 200 ℃ and a nozzle feed pressure of 20 MPa.

TABLE 2 composition of the intermediate protein samples

	Recovered wet protein
				Protein concentrate 1 (acid pH4.6)	Protein concentrate 2 (rennet + acid pH4.6)
Water content%	52.2	55.4
			Fat%	0.20	0.35
Protein (TN × 6.38)%	44.6	41.5
			Ash content%	1.40	1.37
Ca(mg/kg)	5,540	1,230

TABLE 3 analysis of protein salt component sample powders

	Protein concentrate 1+ NaOH + Natural WP	Protein concentrate 1+ Ca (OH)2+ modified WP	Protein concentrate 2+ NaOH + denatured WP
				Protein (TN × 6.38)%	88.6	85.5	84.3
Casein%	75.0	80.3	78.3
				Whey protein%	12.2	4.1	4.8

WP/casein	0.16	0.05	0.06
				Water content%	4.08	3.31	4.26
Ash content%	4.29	4.96	5
				Fat%	1.74	1.38	1.98
Lactose%	4.23	4.06	4.37
				Total of*	102.94	99.21	99.91
Ca(mg/kg)	2790	14900	7250
				K(mg/kg)	2900	2520	2830
Mg(mg/kg)	333	335	366
				Na(mg/kg)	10800	1330	9140
P(mg/kg)	6310	6560	6620

^*Casein, whey protein, moisture, ash, fat and lactose

The proteinate component powders in Table 3 were prepared with calcium concentrations of 2790-14,900mg/kg and sodium concentrations of 10,800-1330mg/kg, and were subjected to a series of protein treatments. It will be appreciated by those skilled in the art that various combinations of other proteinate components can be achieved based on the present invention by making minor modifications to the above procedure or combining two or more solution process products in different proportions prior to the concentration or drying stage.

Example 5 preparation of a processed cheese spread

Formulation of paint sample

The three proteinate component powders in table 3 were used to make a processed cheese spread (spread) formula and tested for their ability to form an acceptable spread and their texture determined. The control powder was used as reference. Standard 70% milk protein concentrate [ MPC70 ] was used](ALAPRO 4700^TMOklan, ltd, skara corporation) component powder a control smear was prepared.

Protein component composition

The proteinate component used for the spread had the composition shown in table 3, and the MPC70 control had the composition shown in table 4.

TABLE 4 composition of the components

Components	ALAPRO 4700TM(control)
		Fat%	0.96
Protein%	72.9
		Lactose%	17.2
Ash content%	7.54
		Water content%	3.81
Na(mg/kg)	210
		Ca(mg/kg)	2010

Paint samples were prepared using the formulations of table 5.

TABLE 5 formula of the spread

Components	Control (ALAPRO 4700)TM)	Protein concentrate 1, NaOH, Natural WP	Protein concentrate 1, (Ca)2OH, denatured WP	Protein concentrate 2, NaOH, denatured WP
					Soybean oil (g)	185.5	185.5	185.5	185.5
Protein component (g)	85.1	69.0	68.9	70.4
					Lactose (g)	3.2	18.3	18.0	17.2
TSC(g)	13.28	15.23	14.79	14.73
					CA(g)	3.35	1.40	1.84	1.90
Salt (g)	6.0	6.0	6.0	6.0
					Water (g) (including evaporation allowing 11.0 g)	297.6	298.6	299.0	298.3
In total (g)	594.03	594.03	594.03	594.03
					Humidity (%)	51.2	51.45	51.35	51.35
Measured pH	5.72	5.78	5.77	5.77

TSC is trisodium citrate

CA ═ citric acid

Preparation method of smearing matter

The spread was prepared using a 2L capacity Vorwerk Thermomix TM 21 mixer-cooker (Vorwerk australia pty. ltd., Granville, new south wales, australia) and the method described below.

The proteinate component, e.g., MPC70 (70% protein (dry weight)) was hydrated in a Salt solution (13.28g trisodium citrate (Jungbunzlauer GmbH, Perhofen, austria), 3.35g citric acid (Jungbunzlauer GmbH, Perhofen, austria), 6.0g sodium chloride (Pacific Salt, Christchurch, new zealand) and 200g water). The mixture was allowed to stand at 4 ℃ overnight.

Temperature set to 100, speed set to 1, Soybean oil (AMCO)^TMGofmanfielder, okland, new zealand) for 1 minute (this allows the oil temperature to reach 60 ℃).

To the oil was added the hydrated proteinate component (MPC70), lactose and the remaining water (97.6 g). The mixture was cooked for 7 minutes at a speed set at 4(2000rpm) and a temperature set at 85 ℃. At the end of each minute, the speed was set to "accelerate" (12,000rpm) for 3 seconds, thereby thoroughly mixing the emulsion and preventing the emulsion from burning and sticking to the cooker walls. The hot emulsion was then poured into plastic jars with screw caps, inverted and stored at 4 ℃. The final pH of the spread was 5.75 ± 0.05.

The texture of the stored spread samples was determined after 1 week.

Composition of the emulsion

The emulsion contained 51.0% moisture, 31.4% fat, 10.0% protein, 5.9% lactose and 1.7% other residues.

Texture of processed cheese spread samples

The texture of processed cheese prepared using the ingredients described in the present invention was determined and compared to a control prepared using a standard MPC70 ingredient. The texture was analyzed by determining the modulus of elasticity G' of the resulting product sample. The modulus of elasticity was determined using a texture analyzer TAAR2000 rheometer (TAInstructions-Waters LLC, New Cork., USA) at 20 ℃, 0.1Hz and 0.005 tension using the methods described in Li S.K, (Lee S.K.) and Krastomer H, (Klostermeyer H.), Lebensm-Wiss.U-Technol., 34, 288-. (A detailed description of the modulus of elasticity is available from French J.D, (Ferry, J.D.) eds., "tackiness of Polymers (Viscoelastic Properties of Polymers), 3 rd edition, New York. John Wiley & sons.1980). The gel strength was determined repeatedly by taking different samples from the same batch of product (different jars).

The measured value G' of the texture of the spread is shown in table 6.

TABLE 6 comparison of spread texture

Proteinate compositions	Control (ALAPRO 4700)TM)	Protein concentrate 1, NaOH, Natural WP	Protein concentrate 1, Ca (OH)2WP being denatured	Protein concentrate 2, NaOH, denatured WP
					Texture G' (Pa)	199,177	737,874	44,50	164,145

The proteinate component of the invention may be used to prepare processed cheese spreads having different textures.

Claims (36)

1. A method of producing a protein composition from a dairy stream comprising the steps of:

a) subjecting the milk stream to conditions which result in the formation of a protein concentrate and a serum;

b) separating the protein concentrate and the serum;

c) dissolving the separated protein concentrate in an aqueous solution;

d) combining the solubilized protein concentrate with the separated whey to form the protein composition; and

e) concentrating the protein composition formed in step d).

2. The process of claim 1, wherein the conditions of step a) comprise adjusting the pH of the milk stream to 4.5-4.8, followed by heating to form a protein concentrate and a serum.

3. The process of claim 1, wherein the conditions of step a) comprise adding to the dairy stream an enzyme capable of converting kappa-casein to para-kappa-casein, followed by heating to form a protein concentrate and a serum.

4. The process according to claim 1, wherein step a) comprises dividing the aqueous medium of a milk stream containing the milk proteins into two parts,

adjusting the pH of a part of the mixture to 4.5-4.8,

adding to the other part an enzyme capable of converting kappa-casein to para-kappa-casein, and

the two fractions are combined and the combined stream is heated to form a protein concentrate and a serum.

5. The method of any one of the preceding claims, wherein the dairy stream is skim milk.

6. The method of any one of the preceding claims, wherein the dairy stream is pasteurized.

7. A process as claimed in any one of the preceding claims wherein the milk stream is subjected to a membrane concentration step.

8. The method of claim 7, wherein the membrane concentration step is an ultrafiltration step.

9. A process according to claim 2 or 4, wherein the pH of the milk stream or a part thereof is adjusted by adding an acid, preferably a food approved acid, more preferably hydrochloric or sulphuric acid.

10. A process according to claim 2 or 4, wherein, when the milk stream contains lactose, the pH of the milk stream or a part thereof is adjusted by adding a starter culture to ferment part of the lactose to acid, most commonly lactic acid.

11. The method of claim 10, wherein the starter culture is any food-approved bacterial culture capable of fermenting lactose to form acids.

12. The method of claim 11, wherein the bacterial culture is a strain of lactobacillus.

13. The method of any one of claims 2, 4, and 9-12, wherein the pH is adjusted to 4.6.

14. A process as claimed in claim 3 or 4 wherein the further milk stream is reacted with the kappa casein converting enzyme at a temperature of less than about 15 ℃, more preferably less than 10 ℃.

15. The method of claim 14, wherein the kappa casein converting enzyme is chymosin.

16. A process according to claim 14, wherein the kappa casein converting enzyme is rennet, preferably derived from animal or microbial sources.

17. A process according to any one of claims 2 to 16 wherein the protein concentrate and serum are formed by heating to a temperature of from about 25 ℃ to 70 ℃, more preferably from 30 ℃ to 55 ℃, most preferably from 40 ℃ to 50 ℃.

18. The method of claim 17, wherein the heating is done for a period of 1-600 seconds, preferably 5-200 seconds, more preferably 10-50 seconds.

19. The process of any one of the preceding claims, wherein the protein concentrate isolated from step b) is washed with water.

20. The method of any one of the preceding claims, wherein the protein concentrate isolated in step b) is milled.

21. The method according to any one of the preceding claims, wherein in step c) the protein concentrate is dissolved in an alkaline solution.

22. The method of claim 21, wherein the alkali solution contains cations comprising sodium, potassium, calcium, magnesium, or mixtures thereof.

23. The method of any one of the preceding claims, wherein the protein level of the whey isolated in step b) is adjusted by adding, removing or engineering the protein.

24. The process of any one of the preceding claims, wherein the whey separated in step b) is concentrated before being combined with the solubilized protein concentrate in step d).

25. The process of any one of the preceding claims, wherein the whey separated in step b) is further separated into a protein-rich stream and a lactose-rich stream.

26. The process of claim 24 or 25, wherein in step d) said concentrated protein solution is mixed with all or part of said protein-enriched whey stream and all or part of said lactose-enriched stream to form said protein composition.

27. The process of any one of the preceding claims, wherein fat, oil or cream is added to the protein composition formed in step d).

28. The method of any one of the preceding claims, wherein the protein composition is homogenized.

29. The method of any one of the preceding claims, wherein the protein composition is dried.

30. A process as claimed in any one of the preceding claims wherein the protein composition is used to prepare cheese.

31. A protein composition prepared according to any one of claims 1 to 29.

32. A cheese made using the protein composition of claim 31.

33. A milk proteinate composition comprising para-kappa-casein and whey protein, which composition does not form a gel when concentrated.

34. The proteinate composition of claim 33 having a calcium concentration of 2,700mg/kg to 15,000mg/kg and a sodium concentration of 11,000mg/kg to 1,300mg/kg on a dry basis.

35. A powder of the milk proteinate composition of claim 33 or 34.

36. A cheese prepared using the proteinate composition of any of claims 33-35.