AU2004202348A1 - Particulate Cheese Curd Product - Google Patents

Description

2004-MAY-31 02:39PM FROM- T-360 P.004/024 F-034 Regulation 3.2

AUSTRALIA

PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventors: Address for service in Australia: Invention Title: CRAIG GRAHAM HONORE, ANDREW JOHN FLETCHER, NICOLA JAN WHITE, RICHARD ARCHER, PAUL ELLOITT MULLIGAN CRAIG GRAHAM HONORE, ANDREW JOHN FLETCHER, NICOLA JAN WHITE, RICHARD ARCHER, PAUL ELLIOTT MULLIGAN A J PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT 2601, Australia Particulate Cheese Curd Product The following statement is a fll daesiption of this invention, including the best method of performing it known to me.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-3I 02:39PM FROM- T-360 P.005/024 F-034 2 BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a cheese curd or young cheese for use in making processed cheese and processed cheese made therefrom. It also relates to a proces for manufacturiug a curd or young cheese and to the manufacture of processed cheese therefrom.

Processed cheese is made by combining mixtures of young cheese and of mat'ed (flavoured) cheese and other ingredients together to obtain the desired combination of composition, texture and flavour. An important attribute of young cheese for this purpose is that it has a high level of intact casein. Intact casein is variously categorised as functional casein, relative casein, srrcturd casein, fumetional protein and structural protein. All of these meanings and any others understood in the art are intended to be encompassed by this specification.

The terms "curd" and "young cheese" are used interchangeably in this specification. To practise this invention there is no need to determine the precise transition point between them.

Description of the Related Art A cheese may be said to have a life cycle which is divided into three phases. The first of these is the functional phase when the functional properties are predominant. In the second phase the cheese has lost most of its fimctional properties but not yet developed its flavour. It is used as a filler in the second phase. In the third phase the cheese has ripened to release its flavours. It is a combination of bacterial and enzymatic action causing the maturation or ripening of cheese during the three phases which results in a progressive breakdown of intact casein. It is of benefit to be able to extend the functional or first phase of the cheese aging cycle. It allows the manufacture of cheeses using the functional properties over a greater period of time. Where a market is remote from where the young cheese is made, delays in transport do not cause a loss in value. It also allows cheese to be manufactured over twelve months of the year, rather than being tied to the milking season, One way of slowing or arresting cheese maturation and the breakdown of intact casein is to chill or freeze the young cheese. In US patents 5,773,054 and 5,783,236 there is described a process for producing a young cheese in a particulate form. Fresh cheese curd is drained, COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:39PM FROM- T-360 P.OO/OZ4 F-034 3 salted and milled and cooked in a particulate form. The product is then cooled and optionally dried to a mininurn moisture content of 33 to 36% The effect of the drying and cooling processes is to yield fresh curd particles which do not knit when they are packaged in bulk and stored. The product may optionally be allowed to mature and is not stable to bacterial or enzymatic maturation processes.

Where young cheese is supplied in bulk (for example 200 kg blocks) it cannot be cooled quickly enough to slow or halt the initial proteolysis reaction.

It would be desirable to be able to produce a cheese curd or a young cheese without the expense of chilling or freezing. Such a stabilized cheese curd would then be able to be made into processed cheese at a site and time chosen by the processed cheese manufacturer.

It is an object of this invention to go some way towards achieving these desideratum or at least to offer the public a useful choice.

Summary of the uInvention Accordingly, the invention may be said broadly to consist in a method for producing a partmiculate cheese curd suitable for the preparation of a processed cheese comprising the steps of: forming a coagulum of cheese curd from milk, salting said coagulum and draining whey therefrom to form a curd, forming said curd into particles with a particle size suitable for drying, and drying said formed curd particles to a moisture level between 5% and 30% Preferably, said coagulum is formed by adding any source of clotting enzyme or any clotting enzyme to milk.

Preferably said source of dclotting enzyme is rennet COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:40PM FROM- T-360 P.007/024 F-034 4 Alternatively, said coagulum is farmed by adding food grade acid to milk.

In a third alternative said coagulum is formned by adding both a source of Clotting enzyme and a food grade acid.

in one alternative said cud is formed into particles by stirring said coagulum.

In another alternative said curd is formed into particles by milling.

In one alternative said milk is whole milk.

In another alternative said milk is skim milk.

In a third alternative said milk is a cheese milk.

Preferably, said curd is milled to a particle size no greater than 20 mm mesh.

More preferably, said curd is railled to a particle size no greater than 10 mmn mesh.

More preferably, said curd is milled to a particle size no greater than 7.5 mm mesh.

More preferably, said curd is milled to a particle size no greater than 4 mm mesh.

Most preferably, said curd is milled to a particle size no greater than 3 mm mesh, Preferably, said curd particles are dried to a moisture level of from 5 to 25% More preferably, said curd particles are dried to a moisture level of 22 to 23% In one alternative said drying step is a batch process.

In another alternative said drying step is a continuous process.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:40PM FROM-T-6 P.0/4F04 T-360 P-000/024 F-034 Preferably, said continuous process comprises one or more stages carried out ill Parallel Or in sequence.

Preferably, said curd particles ame dried with a fluid bed dryer.

More Preferably, said dryer is a multi-stage fluid bed dryer.

In one embodiment, where said dryer is a multi-stage fluid bed dryer, partially dried curd is milled after emerging from one stage and before entering a nt stage.

Preferably, said curd particles, arc dried with an air dryer with its air temperature in the range of 20 0 C to 80 0

C.

More preferably said temperature is in the range of 20 0 C to 50 0

C,

Preferably said particulate curd is dried under conditions where it is not heated to above the melting point of any fat c-ontainead therein.

1n one embodiment after said curd particles are formed, they are salted.

In another embodiment the invention may be said broadly to consist in a particulate cheese cud produced by the process described herein above.

In another embodiment the invention may be said broadly to consist in a particulate cheese 2$ curd having a particle size no greater than 20 mm mesh and having a moisture content between 5% =nd 30% Preferably, said particle size is no greater than 10 mm mesh.

More preferably, said particle size is no grieater than 7.5 Muin mesh, More preferably, said particle size is no greater tha 4 mm. mesh.

Most preferably, said particle size is no greater than 3 mm mesh.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:40PM FROM- T-360 P.009/024 F-034 6 Preferably, the moisture content of said particles is between 5 and 25% Most preferably, the moisture content of said particles is from 22 to 23% The invention may also be said broadly to consist in the use of a particulate chee-se curd as defined above in the manufacture of processed cheese.

The invention may also be said to consist in a processed cheese produced using a particulate cheese curd as defined herein.

This invention may also be said broadly to consist in 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 said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents arc deemed to be incorporated herein as if individually set forth.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

Brief Description of the Drawings The invention may be more fully understood by having reference to the accompanying drawings wherein: Figure 1A represents the control in Example 3. It is a plot of the log-linear levels of decay of a, casein and P casein against time in a particulate curd control sample with a moisture content of 32.5% Figure 18 represents trial I in Example 3. It is a plot of the log-linear levels of decay of a.l cascin and [3 casein against time in a particulate curd sample dried to a moisture content of 22-23% COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-3i 02:4OPM FROM- T-360 P.010/024 F-034 7 Figure IC represents tral 2 in Example 3. It is a plot of the log-linear levels of decay of casein and casein against time in a particulate curd sample dried to a moisture content of 28-30% Figure ID represents trial 3 in Example 3. It is a plot of the log-linear levels of decay of casein and pi casein against time in a particulate curd sample dried to a moisture content of 22-23% Figure IE represents trial 4 in Example 3. It is a plot of the log-linear levels of decay of casein and P casein against time in a particulate curd sample dried to a moisture content of 28-30% Figure 2 represents a plot of measured breakdown rates of ag. casein and j3 casein in the cheee curd versus cheese curd moisture level.

Detailed Description of the Preferred Embodiments We have discovered that drying reduces the rate of breakdown of selected casein proteins in a particulate cheese curd or young cheese. It is believed that the state of the selected proteins reflects the level of intact cascin in cheese.

Cheese curd, or cheese-like curd including skim milk chcese curd, may be produced by any means known in the art. Typical methods for producing cheese curd are described in Koslkowsky et al (1997).

In one embodiment, upon the completion of salting and the draining of any excess whey, fresh cheese curd is milled and fed into a dryer. The dryer may be batch or continuous and may consist of one or more stages used in parallel or in sequence.

In an alternative embodiment the whey and curds are stirred continually during cooking.

After removal of whey, the curd continues to be stirred during subsequent stages of curd handling including salting. When such a step is employed ftuther milling may not be required to put the curd into a particulate form for drying, COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:41PM FROM- T-360 P.011/024 F-034 8 A preferred design of dryer is a fluid bed dryer and a more preferd dryer is a multi-stage fluid bed dryer. Optionally between dryer stages further curd milling, size reduction or screening devices may be deployed.

The dryer is supplied with a drying medium. A preferred drying medium is air and more preferably the air is heated. Optionally the drying medium may be dehydrated or dehumidified prior to entry to the fluid bed or contact with the material to be dried.

Optionally the drying medium may be recycled.

At the exit of the dryer, the curd particles have a preferred moisture content between 5% and about 30% by weight.

In a preferred embodiment, the air to the dryer should be less than 80°C and greater than 200C. Optionally the characteristics of the drying medium (temperature and humidity) supplied to the various stages may be varied between the stages.

Further, we have discovered that we can obtain very desirable intact casein preservation levels at moisture concentrations that serendipitously halt the growth of spoilage organisms at ambient temperature. Thus in a preferred embodiment it is convenient to store the dried product at ambient temperature.

Optionally, the dried product may be stored at below ambient temperature and preferably below 0°C.

EXAMPLE 1: Preparation of Curd for Drying Cheddar-style cheese curd was prepared as follows.

A cheese vat was filled with 375 L of pasteurized milk that had been standardized to a protein to fat ratio of 0.78. The temperature of the cheese milk was adjusted to 32°C. Mesophilio starter at the rate of 2.4% of cheese milk, coagulant at the rate of 6 mUl/ 00 L of cheese milk and CaC12 at the rate of 0.02% were added and thoroughly mixed with the cheese millk COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:41PM FROM- T-360 P.012/024 F-034 9 After about 20 minutes setting, the gel was cut using a 6 nmmn curd knife. While being stifed, the curds and whey were then heated to 38.5°C over a period of 40 minutes anid allowed to cook.

The whey was drained from the curds after a further 2% hours. The curd was stired six times in the first lg minutes, then three times in the following 15 minutes and then once every minutes. Once the pH had reached approximately 5.2, salt was added to the cord at the rate of 22g/kg. The curd was mellowed a further 20 minutes.

EXAMPLE 2! Drying of Curd Four 9kg batches of milled curd prepared in a manner similar to that in example I were dried using a low humidity, low temrperature dryer. The samples of curd were dried over two days at 10°C. Approximately 9 kg of curd was weighed out onto 12 drying stainless steel drying trays, and this procedure was repeated with 4 separate drying trials over 2 days. The air temperature, relative humidity and average cheese moisture levels for each dryer trial is shown in Table 1.

Table 1. C Trial No.

1 2 3 4 urd drying conditions.

Air Temp Relathi Range Humid (Inlet) (Outle 34-35 0 C 60-80' 34-350C 60-80/ 34-36C 40- 50 34-36°C 40-50 lity Range 0 Drying Time 4 his 1.5 hrs 2 brs 1.25 hrs Final Average Curd Moisture w/W 22.5 28.2 21.8 29.5 The average composition of the dried curd samples is shown in Table 2.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:41PM FROM- T-30 P,013/024 F-034 Table 2. Composition of dried curd samples.

Moisture Fat pH Salt Protein S/M FM MNFS w/w) w/w) w/w) w/w) Control 32.5 36.5 5.55 1.5 24.6 5.7 54 51.2 Trial 1 22.5 41.4 2.53 29.3 11.2 53 38.4 Trial 2 28.2 38.0 2.22 26.8 7.9 53 45.5 Trial 3 21.8 41.1 2.70 29.5 12.4 53 37.0 Trial 4 29.5 37.0 2.16- 7,3 52 46.8 1 S/M (Salt in moisture) FDM (Fat in dry matter) MNFS (Moisture in non-fatty substance) EXAMPLE 3: Storage and Proteolysis Measurement Dried cheese samples were stored for an extended period (3months) at 10"C, and sub-sampled at regular intervals. The extent of casein proteolysis was determined using well-established electrophoretic methods (Alkaline Urea PAGE). See Creamer (1991).

The results of the measured casein breakdown from the PAGE analyses were measured and are set out in Figures la to le. The rates of osl and 0-casein decay were plotted and correlated using log-linear plots and showed that drying had a very significant effect on the rate of casein breakdown.

Samples dried to 22-23% moisture (Trials 1 and 3, Figures 1B and ID) had minimal levels of casein decay, >90% of both as, and p-casein remained after 3 months at compared to non-dried control sample (Figure 1A 32.5 moisture) where <20% of asi and approx. 40% p-casein remained after 3 months storage at Samples dried to an intermediate moisture level (28-30% moisture) (Trial 2 and 4, Figures 1C and LE) had lower levels of casein decay of ast and >90% of P-casein remained) after 3 months at 10°C, compared to non-dried control. (Figure 1A).

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:41PM FROM- T-360 P.014/024 F-034 11 The relationship between moisture level of dried cheese curd and the observed rate constants for both as- and P-casein were non-linear in nature, but followed similar trends (refer to Figure 2).

The expcrimenta revealed that at moisture levels of 25% w/w the rate of breakdown of casein in cheese curd was so dramatically reduced that there was a likelihood of maintaining satisfactory intact casein levels for a period of some months at ambient temperature or near ambient temperature.

EXAMPLE 4: Drying of Curd 2 kg of salted and drained cheese curd (moisture 38.4%, fat 31%, protein 25.3%, salt 3.13%) prepared as described in example 1 was in a paniculate form as a reanisult of the stirring after the whey had been removed. A sieve analysis shown in Table 3.

Table 3. Sieve analysis of curd particle size retained) Screen mesh 1 Imm 3 mm 4mm 7.5 mm o size CurdA 1 72 17 10 0 The particulate curd was dried using a Uniglatt batch fluid bed dryer (Glatt Process Technology GmbH, Binzen, Germany) equipped with a Munters dehumidifier (Munters ML 180OE dehumidifier, Munters Europe. Tobo, Sweden) fitted to the dryer air supply.

The dehumidified air had a relative humidity of 6% at 27C (absolute humidity 1.3 g/kg dry air). The inlet air was electrically heated to 28°C prior to entering the fluid bed. An airflow of 3 kg/min was used.

The moisture content of the curd in the dryer was deterined by withdrawing small samples (approximately 16 g) at regular intervals for analysis (16-hour oven drying method). The fluid bed temperature and the moisture content over the course of the drying are shown In Table 4.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:42PM FROIh T-360 P.015/024 F-034 Table 4.

Experimental drying results for sample 1 EXAMPLE 5: Preparation of a Processed Cheese from Dried Curd The ingredients in table 5 were reduced to a uniform particle size by passing through a 5 mm cheese grinder and then placed in a 25 kg capacity Blentech (model no. CC45) cooker.

Table S. Initial Ingredients Ingredients Dried cheese curd (22% moisture) Young cheese Medium cheese Mature cheese Butter Kg 3.500 0.400 2.975 1.200 0.800 The ingredients in table 6 were also added to the cheese in the Blentech cooker.

Table 6 Additional Ingredients COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:42PM FROM- T-360 P.016/024 F-034 13 The mixtur was blended using an auger speed of 120 rpm. 0.026 kg of citric acid was added and the mixture was heated to 87°C over a period of about 1 minute using direct steam injection. This temperature was maintained for about 6 minutes. During the heating, approximately 1.47 kg of condensate was added and incorporated into the mixture.

The molten mixtore was poured through a colloid mill before being cast on a chilled table, whereupon the film of cheese was cut into slices. The chilled slices were a processed cheese slice of acceptable quality for IWS application.

It is not the intention to limit the scope of the invention to the abovementioned examples only.

As would be appreciated by a skilled person in the art, many variations are possible without departing from the scope of the invention.

References Creamer, L.K, (1991) Electrophoresis of cheese. Bull Int Dairy Fed 261, 14-28.

Kosikowsld F.V. Mistry V.V. Cheese and Fermented Milk Foods. Volume 1: Origins and Principles 3 rd ed. 1997. Chapts. 7 13. Kosikowsld, Great Falls, Virginia 22066, USA.

COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31

Claims (4)

1. 2004-MAY-31 02:42PM FROM- T-360 P,01T/024 F-034 14 SCAIMS EFINING THE INVENTION ARE AS FOLLOWS: 1. A method for producing a particulate cheese curd suitable for the preparation of a processed cheese comprising the steps of: forming a coagulum of cheese curd from milk, salting said coagulum and draining whey therefrom to form a curd, forming said curd into particles with a particle size suitable for drying, and diying said formed curd particles to a moisture level between 5% and 30%
2. 2. The method of claim 1, wherein said coagulum is formed by adding any source of clotting enzyme or any clotting enzyme to milk-
3. 3. The method of claim 2, wherein said source of clotting enzyme is rennet.
4. 4. The method of claim I, wherein said coagulum is formed by adding food grade acid to milk. The method of claim 1, wherein said coagulum is formed by adding both a source of clotting enzyme and a food grade acid. 6. The method of any one of the preceding claims, wherein said curd is formed into particles by stirring said coagulum. 7. The method of any one of claims 1 to 5, wherein said curd is formed into particles by milling. 8. The method of any one of the preceding claims, wherein said milk is whole milk. 9. The method of any one of claims 1 to 7, wherein said milk is skim milk. The method of any one of claims I to 7, wherein said milk is a cheese milk. COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-Si 02:42PM FROM-T-0P.1/2 F-3 T-360 P-018/024 F-034 11, The method of claim 1, wherein said curd is milled to a particle size no greater than 20 mm mesh. 12. The method of claim 7, wherein said cud is, milled to a particle size no greater than 10 mwl mecsh. 13. The method of claim 7, wherein said curd is milled to a particle size no greater than mesh. 14. The method of claim 7, Wherein said curd is milled to a particle size no greater than 4 mun mesh. The method of claim 7, wherein said curd is milled to a particle size no greater than 3 rm mesh. 16. The meteod of any one of the preceding claims, wherein said curd particles are dried to a moisture level of from 5 to 25% 17. The method of any one of claims 1 to 15, wherein said curd particles arc dried to a moisture level of 22 to 23% 18. The method of any one of the preceding claims, wherein said drying step is a continuous process. 19. The method of claim 18, wherein said continuous process comprises one or more stages carried out in parallel or in sequence. The method of any one of claims I to 17. wherein said drying step is a batch process. 21. The method of any one of the preceding claims, wherein said curd dried particles are with a fluid bed dryer. 22. The method of claim 2 1, wherein said dryer is a multi-stage fluid bed dryer. to F nflf( COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:42PM FROM-T-6 P.1/4Ffl T-360 P-019/024 F-034 16 23. Thbe method of claim 22, wherein partially dried curd is milled after emerig from One stage and before entering a next stage. 24. The method of any one of claims I to 20, wherein said curd particles are dried with an air dryer with its air temperare in the range of 20 8 C to 80 0 C The method of claim 24, wherein said temperat=r is in the range of 20'C to 50 0 C. 26. The~ method of any one of the preceding claims, wherein said particulate curd is dried under conditions where it is not heated to above the melting point of any fat contained therein. 27. The method of any one of the preceding claims, wherein after said curd particles are formed they are salted. 28. A particulate cheese curd produced by the process of any one of the preceding claims. 29. A particulate cheese curd having a particle size no greater than 20 mmn mesh and having a moisture content between 5% and 3 0% A cheese curd as claimed in claim 29, wherein said particle size is no greater than 10 mm mesh. 31. A cheese curd as claimed in claim 29, wherein said particle size is no greater than 7.5 mmr mesh. 32. A cheese curd as claimed in claim 29, wherein said particle size is no greater than 4 mm mesh. 33. A cheese curd as claimed in claim 29, wherein said particle size is no greater than 3 mm Mesh. 34. A cheese curd as claimed in any one of claims 29 to 33, wherein the moisture content of said particles is between 5 and 25% (WJWT). COMS ID No: SBMI-00771 958 Received by IP Australia: Time 12:50 Date 2004-05-31 2004-MAY-31 02:43PM FROM- T-30 P-00/024 F-034 17 A cheese curd as claimed in any one of claims 29 to 33, wherein the moisture content of said particles is from 22 to 23% 36. The use of a particulate chese curd as claimed in ay one of claims 28 to 34 in the manufacture of processed cheese. 37. A processed cheese produced using a particulate cheese curd as claimed in any one of claims 29 to 38. A method as claimed in claim 1 substantially as herein desbed with reference t any example thereof. 39. A cheese curd as claimed in claim 28 substtially as herein described with reference to any example thereof. A cheese curd as claimed in claim 29 substantiall as herein desribed with reference to any example thereof. 41. The use as claimed in claim 36 substantially as herein described with reference to any example thereof. 42. A processed cheee as claimed in claim 37 substantially as herein described with reference to any example thereof. COMS ID No: SBMI-00771958 Received by IP Australia: Time 12:50 Date 2004-05-31