Production of cheese

Abstract

There is provided a process for treating beta-casein to form a fibrous high-moisture content cheese product, such as a mozzarella-style cheese product, by first providing a beta-casein solution, optionally adding a fat to form an emulsion, and then forming a gel via acidifying the starting solution emulsion and / or the addition of a calcium salt to the starting solution emulsion. The coagulated product formed can be processed using standard cheese processing steps to produce a mozzarella-style cheese product. Since beta-casein is the primary protein source used to form the mozzarella-style cheese product, it uniquely contains a high proportion of beta-casein. Camel beta-casein can be used.

Description

[0001] PRODUCTION OF CHEESE

[0002] Technical Field

[0003] The present invention relates to a production process for forming a pasta filata-style cheese product, for example a mozzarella-style cheese product, using beta-casein (“P-casein”) as the primary protein source within the cheese. Since beta-casein is the primary protein source used to form the mozzarella-style cheese product, it uniquely contains a high proportion of beta-casein.

[0004] Background to the Invention

[0005] Protein is a key nutritional requirement and forms a key component of human and animal diet. Proteins can be animal derived (for example, meat, fish, milk or eggs) or can also be sourced from plants, for example legumes.

[0006] In milk the casein proteins exist mainly in a colloidal particle known as the “casein micelle”. The term “casein micelle” describes colloidal calcium phosphate-casein particles in milk. The casein micelle is an assembly of four different casein proteins: asi-casein, aS2-casein, [3-casein and K-casein which are present in a weight ratio of about 4:1 :4:1 . In the casein micelle, the K-casein is predominantly located at the surface of the micelle and forms a “coat” or outer layer in the micelle, with the other remaining caseins being located in a more hydrophobic micellar core. Thus, the K- casein is responsible for maintaining the other caseins in solution. Colloidal calcium phosphate stabilizes the micellar casein structure.

[0007] Traditional cheese formation relies upon the use of the proteolytic enzyme chymosin, also known as rennin, which hydrolyses K-casein between amino acid nos. 105 and 106 leading to removal of a hydrophilic C-terminal fragment (“glycomacropeptide”) from the K-casein. When chymosin is added to micellar casein, the K-casein is hydrolysed and the truncated K-casein, called para-K-casein, formed by removal of the glycomacropeptide remains associated with the casein micelle. However, once cleaved by chymosin, the para-K-casein has insufficient residual hydrophilicity to fully stabilise the micelle and, as a consequence of the K-casein hydrolysis, the micelles aggregate together into para-casein-micelles and finally coagulate sufficiently to form a gel. In milk, at least 70-80% of the K-casein must be hydrolysed for coagulation to occur. Treatment of micellar casein using chymosin is used in the process of forming a pasta filata style or fibrous cheese product, such as mozzarella cheese, where chymosin- induced gel formation is a key step in the traditional process. A pasta filata style cheese, such as mozzarella, is typically also characterised by a filamentous texture and may exude water when cut. The cheese may be a high moisture content cheese product.

[0008] Milk-derived caseinates are produced by precipitating micellar casein at their isoelectric point followed by neutralisation to solubilise the single caseins again. However, re-solubilisation does not lead to the re-formation of casein micelles and the casein proteins remain in solution as caseinates. Such non-micellar casein can be used to form processed and analogue cheese by mixing and cooking the ingredients to form a homogenous solid texture. An “analogue cheese” is a cost- effective cheese-like product in which milk proteins and / or milk fat are replaced by proteins and fat which are not native to milk, for example caseinates and / or vegetable oils. Generally, an “analogue cheese” is produced by blending individual constituents, including non-dairy fats or proteins. Addition of chymosin to the caseinate solution does not lead to the formation of a gel (although the K-casein is still hydrolysed, there are no micelles to aggregate together). To date, non-micellar casein has not been used to form a fibrous pasta filata style cheese product, such as high moisture mozzarella. Rather, such cheese products are produced using casein micelles, as described above, and therefore require a cost intensive processing step. Additionally, to date, a pasta filata cheese product relies upon the presence of all of the casein proteins, including K-casein.

[0009] The present invention provides a process for forming a pasta filata (fibrous) cheese product using beta-casein as the primary protein source. For example, the beta casein can provide at least 80% by weight of the protein content, for example at least 85% by weight of the protein content, or even more. Since beta-casein is the primary protein source used to form the pasta filata fibrous cheese product, the cheese uniquely contains a high proportion (for example 15 to 35 weight %) of beta-casein in the final product. Optionally, the pasta filata (fibrous) cheese is a low-fat or no-fat mozzarella product. Summary of the Invention

[0010] In a first aspect, the present invention provides a process of forming a fibrous or pasta filata cheese product, wherein said process comprises forming an emulsion by providing a protein component (usually prepared as a protein solution with an aqueous solvent) wherein said protein component has a protein fraction which comprises at least 50% by weight beta-casein (optionally at least 70% or 80% by weight beta-casein), optionally admixing said protein component with a fat to form an emulsion, and inducing gel formation by addition of acid (for example by acidifying the protein solution or emulsion) and / or by the addition of a calcium salt such as CaCh Optionally the addition of the calcium salt (CaC ) can be conducted with addition of an alkali to increase the pH, for example to pH 6 or higher. Generally, where the pH is alkaline, the calcium salt is added to induce gel formation. Optionally, temperature changes can also be used to promote gel formation. The coagulated product formed by gel formation can be processed using standard cheese processing steps to produce a pasta filata style (for example mozzarella-style) cheese product. The end product can be a high moisture cheese product.

[0011] The pasta filata style cheese product obtained forms a further aspect of the present invention. Optionally, the cheese product can be a high moisture mozzarella-style product.

[0012] Also provided is a pasta filata style cheese product which comprises at least 15% by weight [3-casein. The cheese product can conveniently be a mozzarella-style cheese product.

[0013] Optionally, the pasta filata (fibrous) cheese is a low-fat (e.g., less than 30% fat relative to the weight of the protein) or is a no-fat mozzarella product.

[0014] Optionally, the beta-casein comprises camel beta-casein.

[0015] Brief Description of the Figures

[0016] Figure 1 is a flow chart showing a typical prior art process for forming mozzarella using micellar protein from milk. Figure 2 is a flow chart of the process of the present invention.

[0017] Figure 3 shows the a) the curd during stretching; b) the moulded cheese; c) the inside of the moulded cheese and d) the cheese after melting.

[0018] Figure 4 shows the cheese of Example 1 , in particular a) shows the moulded cheese cut in half, and b) shows the fibrous structure inside the moulded cheese.

[0019] Figure 5 shows the cheese of Example 2, in particular a) shows the curd during texturization, and b) shows fibrous structure inside the moulded cheese.

[0020] Figure 6 shows the cheese of Example 3, in particular a) shows the curd, and b) shows the cheese.

[0021] Figure 7 shows the effect of increasing pH on the solubility of camel beta-casein for DSP-10 (50% purity of camel beta casein) and DSP 009 (70% purity camel betacasein).

[0022] Figure 8 shows the effect of calcium ion addition of the solubility of camel beta-casein (tests performed in duplicate) for a 50% purity camel beta casein (labelled as DSP- 10) and a 70% purity camel beta casein (labelled as DSP-009).

[0023] Figure 9 shows protein gel formation for DSP-10 (50% purity camel beta casein) admixtures.

[0024] Figure 10 shows A: the nucleotide sequence for recombinant camel beta casein and B: the amino acid sequence for recombinant camel beta casein as used in Example 4.

[0025] Detailed Description of the Invention

[0026] The process of the present invention is now described in further detail.

[0027] In a first aspect, the present invention provides a process of forming a fibrous or “pasta filata” style cheese product, wherein said process comprises a protein component having a protein fraction which comprises at least 50% by weight betacasein, and forming a treated component by: i) acidifying the protein component, and / or ii) the addition of a calcium salt, for example CaCh

[0028] The treated component can be an emulsion (if fat has been added) or can be a solution / suspension. The treated component is then formed into the cheese product. Optionally, the protein component is admixed with a fat to form an emulsion prior to the acidification step and / or before the addition of calcium step.

[0029] Optionally, the protein component has a protein fraction which comprises at least 60% by weight beta-casein, for example at least 70% by weight beta-casein, for example at least 80% by weight beta-casein.

[0030] Optionally, the beta-casein is produced recombinantly. Optionally the beta-casein is camel beta-casein (see Figure 10 for the nucleotide and amino acid sequence for camel beta-casein).

[0031] Optionally, where the treated component (for example treated emulsion) is formed using the addition of a calcium salt, such as CaC , then optionally the emulsion is also treated with alkali to adjust the pH to be at least 6, for example at least pH 7, for example pH7.5 or higher.

[0032] Optionally, the temperature of the emulsion can also be changed (lowered) during formation of the treated component (for example treated emulsion), in order to promote gel formation. Optionally, the temperature will be reduced to 10°C or less than 10°C.

[0033] In the treated component (for example treated emulsion) gel formation can occur, which can lead to a coagulated product. The coagulated product can then be subjected to traditional pasta filata cheese making steps.

[0034] Optionally, the protein component starting material can be in the form of a powder.

[0035] Optionally, the protein component starting material can also include non-protein components, but will typically comprise at least 60% protein (by weight), for example more than 80% protein, for example around 85% protein.

[0036] The protein component will include beta-casein as the primary protein, that is the protein component will include at least 50% (by weight) of beta-casein in the protein fraction (i.e., of the total protein content of the protein component), for example will include at least 60% by weight beta-casein, for example at least 70% by weight betacasein, for example at least 80% by weight beta-casein, for example will include at least 85% (by weight) beta-casein in the protein fraction, for example at least 90% (by weight) of beta-casein in the protein fraction, for example at least 92% (by weight) of beta-casein in the protein fraction. In one example, the protein component starting material comprises 85% by weight of protein, with the protein including 92.3% (by weight) beta-casein. Optionally the protein component is substantially beta-casein. Optionally the beta-casein is a camel beta-casein, which may optionally be produced through recombinant expression.

[0037] Optionally, the “protein component” is formed into a protein solution at the start of the process. The protein solution can be a solution of the protein component in an aqueous solvent, such as water or an aqueous salt solution. Beta-casein will form at least 50% by weight of the protein fraction of the protein solution (optionally will include at least 60% by weight beta-casein, for example at least 70% by weight betacasein, for example at least 80% by weight beta-casein), as is described above for the protein component.

[0038] In the process of the invention the starting material beta-casein is in a free form, i.e., is not in the form of a casein micelle. It is possible for the beta-casein to be induced to form dimers or micelle-like assemblies consisting only of beta-casein. The betacasein can be obtained from the cold microfiltration of milk, for example bovine milk. Other milk sources can alternatively be used. Beta-casein can also be obtained using cold separation using a decanter centrifuge or separator (or any type of centrifuge). For this process the protein solution, suspension, dispersion or emulsion need to be cooled to a temperature below 10 °C and then acidified to precipitate the alpha- and kappa-caseins, which can then be separated via centrifugation. Alternatively, the beta-casein can be produced by recombinant expression using techniques known in the art. Where cold microfiltration of milk is used to provide the beta-casein, the resultant powder can include non-protein components, but will typically comprise at least 60 weight% protein, for example more than 80% protein, for example around 85% protein. The protein component will include beta-casein as the primary protein, that is the protein component will include at least 50% (by weight) of beta-casein (for example at least 60% by weight beta-casein, for example at least 70% by weight beta-casein, for example at least 80% by weight beta-casein), as described above. The protein component will have at least 50% beta-casein in its total protein (the “protein fraction”). Optionally the protein component will have more than 50% betacasein, for example at least 60% by weight beta-casein, for example at least 70% by weight beta-casein, for example at least 80% by weight beta-casein, for example around 85% beta-casein casein on its total protein (the “protein fraction”).

[0039] The beta-casein can conveniently be sourced from cow’s milk. Other suitable sources include milk from other ungulates, such as sheep milk, goat milk, horse milk, donkey milk, camel milk or buffalo milk. Optionally, the beta-casein is sourced from camel milk.

[0040] The beta-casein can also be produced through expression of its gene in a suitable recombinant construct using a suitable host expression system. The term "recombinant" is known by those of ordinary skill in the art. When referring to a nucleic acid (e.g., a gene), the term "recombinant" can be used to describe a nucleic acid that has been removed from its natural context, a nucleic acid that is not associated with all or a portion of a nucleic acid abutting or proximal to the nucleic acid when it is found in nature, a nucleic acid that is operatively linked to a nucleic acid which it is not linked to in nature, or a nucleic acid that does not occur in nature. The term "recombinant" can be used to describe cloned DNA isolates, or a nucleic acid including a chemically-synthesized nucleotide analogue. When "recombinant" is used to describe a protein, e.g., recombinant casein, it can refer to, e.g., a protein that is produced in a cell of a different species or type, as compared to the species or type of cell that produces the protein in nature, e.g., by use of a “recombinant” nucleic acid. Optionally the beta-casein is expressed recombinantly. Recombinantly expressed camel beta-casein is one option.

[0041] In the process of the present invention, the protein component (beta-casein) is first dissolved in an aqueous solution. Typically, a solution containing up to or around 10% (by weight) of beta-casein in water can be prepared. Optionally a salt including an anion able to form a soluble calcium salt can also be included, for example sodium citrate, to facilitate dissolution of the beta-casein. For example, a 10% solution of beta-casein can be prepared by addition of 10g beta-casein in 90g water, optionally with the addition of 0.15g tri-sodium citrate. For example, a concentration of 0.05 to 0.055 mmol citrate per g beta-casein can be used. The dissolution step can be conducted at cold temperatures (for example at about 5 °C) or may be conducted at warmer temperatures, for example at temperatures up to approximately 50 °C. However, at higher protein concentrations the beta casein will agglomerate at temperatures above 50 °C.

[0042] Optionally, the dissolution step is conducted at ambient pressure.

[0043] Dissolution of the beta-casein to form an aqueous solution can be conducted at a temperature of 5-50°C and ambient pressure. For convenience room temperature (20- 25°C) can optionally be used. However lower temperatures (below 10°C) can be beneficial to solvate higher protein concentrations.

[0044] The beta-casein solution used can have a protein content of 1 to 250 g / L, for example 10 to 200 g / L, for example 50 to 60 g / L.

[0045] In one embodiment, the process of the present invention includes the addition of a fat to the beta-casein solution followed by an emulsification step. Optionally, the fat can be an oil at the temperature of the process. Vegetable oil & fat and butter are suitable fats. Suitable vegetable oils include rapeseed oil and sunflower oil, but other vegetable or nut oils can also be used. The fat can be a blend of such oils and / or can be a mixture of oil(s) together with butter. The fat can be added at a ratio of from 3:1 to 1 :3 relative to the weight of the protein, for example a 1 :1 fat to protein ratio. (In a low-fat product, the fat content will be lower than the ratio of 1 :3 relative to the weight of the protein.) After combination, the admixture so formed can be emulsified by any suitable means, for example by simple dispersion, or high-speed stirring and / or by homogenisation. Optionally, the emulsification step occurs at a temperature of from 5°C to 60°C, for example from 30 to 60°C, for example from 45 to 55°C. A temperature of around 50°C can be suitable. Alternatively, a cooler temperature of from 5°C to 25°C can be used. Optionally emulsification step is conducted at a pressure of at least 2,000 kPa (20 bar), for example at a pressure of from 5,000 kPa (50 bar) to 45,000 kPa (450 bar). The emulsification process can be conducted in a two-stage process using a first higher pressure (for example 20,000 kPa (200 bar), followed by a second lower pressure (for example 5,000 kPa (50 bar). The temperature can be of from 5°C to 25°C, for example 20°C.

[0046] The emulsion can be used to form a fibrous content cheese product, such as a mozzarella-style cheese product, through the formation of a gel. The gel formation is induced by acidification and / or the addition of a calcium salt such as CaCh Optionally, gel formation is induced by the addition of a calcium salt (CaC ) with alkalization. Any food grade agent can be used to raise the pH as required. Examples include sodium hydroxide, potassium hydroxide etc.

[0047] One option of inducing gel formation is by acidification. Typically, a pH of 4.0 to 8.0, for example a pH of 5.0 to 6.0, for example a pH of 5.0 to 5.5, is obtained for this step. Optionally, the pH of the starting protein solution or emulsion is about 7.3 and can be between 6.5 and 7.5, depending on protein, citrate and salt concentration. Optionally the starting protein solution or emulsion is chilled prior to acidification, for example to a temperature of 0-20°C, for example to 5-10°C. The cooling step can be conducted over a period of a few minutes, for example around 10 minutes. The exact time taken for cooling the starting protein solution or emulsion is not particularly critical.

[0048] Any suitable food grade acid can be used to achieve the required pH, for example hydrogen chloride, lactic acid, citric acid, acetic acid, D-(+)-glucono-delta-lactone (“GDL”) or any combination thereof. Optionally starter cultures can be used to create the pH reduction by fermentation. Thermophilic and / or mesophilic lactic acid bacteria suitable for the production of yoghurt or cheese are well-known in the art and can be used, like Lactococcus lactis or Streptococcus salivarius. Where fermentation is used to reduce the pH, it is possible to add a sugar (for example up to 2 - 5% by weight relative to the mixture) and to use a temperature from ambient to around 37°C for the fermentation step. Where acids are added to reduce the pH, preferably the acids used are citric acid and / or lactic acid. A pH below 5 may reduce the moisture content of the cheese product. Another option to induce gel formation is by the addition of a calcium salt (and optionally before the acidification step, if present). Typically, the calcium salt will be water soluble, for example can conveniently be calcium chloride (CaCl2). Optionally the starting protein solution or emulsion is chilled or heated prior to the addition of the calcium salt. For example, the starting protein solution or emulsion can be heated to a temperature of 5-60°C, optionally up to a temperature of up to 40°C, for example to a temperature of 20 to 25°C, or can be cooled for example to 10°C. The cooling / heating step can be conducted over a period of a short period, for example around 60 minutes. The exact time taken for cooling the starting protein solution or emulsion is not particularly critical.

[0049] A suitable calcium salt is calcium chloride, but any soluble calcium salt suitable for use in food production can be used. The calcium ions will become bound by the protein so that the reference to “free calcium” refers to the availability of calcium ions to the composition, which will depend upon the solubility of the calcium salt selected and on the calcium to protein ratio. Preferably the calcium salt is calcium chloride, calcium hydroxide, calcium carbonate, calcium citrate, calcium phosphate, stearate malate, calcium glycerophosphate, calcium lactate, calcium gluconate or mixtures thereof. In a particular preferred embodiment of the invention the calcium salt is calcium chloride.

[0050] A further option is to use both acidification and the addition of a calcium salt to induce gel formation. Optionally the acidification of the emulsion occurs first then the calcium salt is added to the starting protein solution or emulsion. Or optionally a calcium salt is first added to the starting protein solution or emulsion and then the acid is added.

[0051] Once the gel has formed, the usual processing steps for a traditional mozzarella-style cheese can be followed. Typically, these steps include the cutting of the curd, a period of repeatedly stirring the cut curd, allowing removal of whey by drainage, plasticization and forming of the cheese, cooling the cheese in a solution at a temperature below 15°C and thereafter storage at a refrigerated temperature in a storage solution (for example 5°C). In more detail, following induction of coagulation due to the addition of the calcium salt I reduction of pH, the coagulated product (curd) can be incubated as described above, and optionally cut and repeatedly stirred during the second half of the incubation period. Thereafter, the whey can be drained from the curd in a manner analogous to the whey drainage step in the formation of a traditional mozzarella-style cheese. Typically, the curd can be placed in a sieve or cloth and the whey allowed to drain for a period of 5 to 60 minutes, for example 5 to 45 minutes. Once the whey has been drained from the curd, the curd can be plasticized pr texturized and formed at a temperature of around 60 to 80°C for a period of up to 5 minutes, for example 1 to 3 minutes. A temperature above 80°C results in a sticky curd, whereas a temperature below 60°C restricts the ability of the curd to stretch. The curd can be texturized in a liquid comprising water (such as water or whey). Conveniently, a ratio of curd: water of from 1 :1 to 1 :10 (by weight) can be used. The stretching liquid can optionally include up to 5% (by weight) of a calcium salt (such as calcium chloride) or a sodium salt, (such as sodium chloride). Thereafter the cheese can be cooled to a temperature below 15°C and stored in a refrigerator (for example at a temperature of around 5°C). Optionally, the cheese can be stored in a storage solution, which is usually an aqueous solution. For example, water can be used to form the storage solution. A suitable storage solution includes, for example, 5 to 25% (by weight) sodium chloride and / or 0.1 to 1 % or more calcium chloride and / or 0.2% (by weight) lactic acid.

[0052] Optionally, the process of the present invention comprises admixing a beta-casein solution with an acid and / or the addition of a calcium salt to form a gel, and further comprising at least one of the following processing steps: a) incubation of the admixture, optionally with regular cutting; and / or b) whey drainage; and / or c) plasticization and forming to produce a cheese product; and / or d) cooling the cheese product.

[0053] Optionally, the beta-casein solution is admixed with a fat to form an emulsion prior to the acidification and / or addition of calcium salt.

[0054] As discussed above, optionally the pH of the emulsion can be increased (alkalized) in combination with addition of the calcium salt. Optionally, the process of the present invention comprises admixing a beta-casein solution with a fat to form an emulsion, cooling or heating the emulsion to a temperature of 5 to 60 °C, followed by the acidification of the emulsion and / or the addition of a calcium salt to the emulsion to form a gel, and further comprising at least one of the following processing steps: a) incubation of the admixture, optionally with regular cutting; and / or b) whey drainage; and / or c) plasticization and forming to produce a cheese product; and / or d) cooling the cheese product.

[0055] Figure 3 shows a cheese according to the invention at different stages of its processing and after melting (d).

[0056] As discussed above, optionally the pH of the emulsion can be increased (alkalized) in addition to addition of the calcium salt.

[0057] Excess kneading of the product during the forming step should be avoided as this can decrease the moisture content of the final product.

[0058] In the present invention, the term “high moisture content cheese product” denotes any cheese food product having a moisture content of 35 to 68% by weight. The moisture content can be determined using an infrared dryer (for example MA 30, Sartorius) with a weighed amount of chopped cheese sample from the inner part of the cheese being heated to a temperature of 105°C until a constant weight is achieved.

[0059] The process can be conducted at standard atmospheric pressure, thereby avoiding any expensive pressurization steps.

[0060] In a further aspect, the present invention provides a high moisture (for example a mozzarella-style) cheese product formed using the process as described above. Since only [3-casein is used as the protein source, no other caseins, for example K- casein, are present to any significant degree within the cheese. Optionally, the cheese is a low-fat or no-fat mozzarella-style cheese product. Thus, the present invention provides a high moisture (for example a mozzarella-style) cheese product formed using beta-casein as the primary protein source, i.e. , includes at least 15% by weight [3-casein and / or includes at least 80% by weight of beta-casein in the total protein fraction.

[0061] In the present invention, the term “high moisture content cheese product” denotes any cheese food product having a moisture content of over 50% by weight. The moisture content can be determined using an infrared dryer (for example MA 30, Sartorius) with a weighed amount of chopped cheese sample from the inner part of the cheese being heated to a temperature of 105°C until a constant weight is achieved.

[0062] In a further aspect, the present invention provides a pasta filata (for example a mozzarella-style) cheese product formed using the process as described above.

[0063] Since only [3-casein is used as the protein source, no other caseins, for example K- casein, are present to any significant degree within the cheese.

[0064] Thus, the present invention provides a pasta filata (for example a mozzarella-style) cheese product formed using beta-casein as the primary protein source, i.e., includes at least 15% by weight [3-casein, for example at least 20% by weight [3-casein. The cheese of the present invention can have a protein content formed by 50% by weight of beta-casein. The total protein content of the sample could be determined using the Kjeldahl method as known in the art. Alternatively the crude protein concentration could be determined according to the Dumas method as known in the art.

[0065] Alternatively, a protein extraction could be done and then the beta-casein content could be determined via HPLC or LC.

[0066] Preferred or alternative features of each aspect or embodiment of the invention apply mutatis mutandis to each other aspect or embodiment of the invention (unless the context demands otherwise).

[0067] All documents referred to herein are incorporated by reference. Any modifications and / or variations to described embodiments that would be apparent to one of skill in art are hereby encompassed. Whilst the invention has been described herein with reference to certain specific embodiments and examples, it should be understood that the invention is not intended to be unduly limited to these specific embodiments or examples.

[0068] Examples

[0069] Example 1 :

[0070] Step 1 ) 2 g p-casein is added to 95.8 g water with the addition of 0.03 g tri-sodium citrate and stirred at room temperature until the protein is fully dissolved.

[0071] Step 2) 2.2 g rapeseed oil is then added.

[0072] Step 3) A high-shear mixer is used to form a pre-emulsion mixture.

[0073] Step 4) The mixture is emulsified using a two-stage homogenizer at 200 / 50 bar (stagel / stage 2) at 20 °C.

[0074] Step 5) The pH of the emulsion is then adjusted using lactic acid (30 %) to pH 5.0, at a temperature of 20 °C.

[0075] Step 6) The emulsion was allowed to rest without stirring for 2 hours at 5 °C to allow curd formation.

[0076] Step 7) Once the curds have formed, the whey is drained off through cheesecloth for 20 minutes at 20 °C.

[0077] Step 8) The curd is texturized in water at a ratio of 1 :2 (curd:water) at 80 °C for 3 minutes.

[0078] Step 9) The texturized curd is placed in a 5 °C cold storage solution (water with 0.1 % lactic acid) for 12 hours.

[0079] The result is a firm white spherical mozzarella-like product with small filaments, with a moisture content of about 55 weight% and a protein and fat content of 21 weight% and 22 weight%, respectively. The pH is about 5. The product can be melted.

[0080] The cheese according to this example is shown in Figure 4.

[0081] Example 2:

[0082] Step 1 ) 4 g p-casein is added to 91 g water, with the addition of 0.06 g tri-sodium citrate and stirred at room temperature until the protein is fully dissolved.

[0083] Step 2) 5 g sunflower oil is added.

[0084] Step 3) A pre-emulsion mixture is formed using a high-shear mixer.

[0085] Step 4) The mixture is emulsified using a two-stage homogenizer at 200 / 50 bar (stagel / stage 2) at 20 °C.

[0086] Step 5) 0.30 g CaCh is added to the emulsion. Step 5) The pH of the emulsion is adjusted using lactic acid (30 %) to give a pH of 6.0. The temperature was 25 °C.

[0087] Step 6) The emulsion was allowed to rest without stirring for 2 hours at 5 °C to allow curd formation.

[0088] Step 7) Once the curds have formed, the whey is drained off through a cheesecloth for 20 minutes at 20 °C.

[0089] Step 8) The curd is texturized in water at a ratio of 1 :2 (curd:water) at 70 °C for 3 minutes , cooling down immediately afterwards to 5 °C by placing the product in chilled water.

[0090] Step 9) The product was stored in 0.1 % cold lactic acid at 5 °C for at least 4 hours.

[0091] The result is a softer white spherical mozzarella-like product with a fibrous structure and a moisture content of about 40% (by weight) and a protein and fat content of 28 weight% and 29 weight%, respectively. The pH is about 6.

[0092] The cheese according to this example is shown in Figure 5.

[0093] Example 3:

[0094] Step 1 ) 2 g p-casein is added to 95.8 g water with the addition of 0.03 g tri-sodium citrate and stirred at room temperature until the protein is fully dissolved.

[0095] Step 2) 2.2 g rapeseed oil is then added.

[0096] Step 3) A high-shear mixer is used to form a pre-emulsion mixture.

[0097] Step 4) The mixture is emulsified using a two-stage homogenizer at 200 / 50 bar (stagel / stage 2) at 20 °C.

[0098] Step 5) The pH of the emulsion is then adjusted using 0.4 % GDL to pH 4.5, at a temperature of 40 °C.

[0099] Step 6) The emulsion was allowed to rest without stirring for 4 hours at 5 °C to allow curd formation.

[0100] Step 7) Once the curds have formed, the whey is drained off through cheesecloth for 20 minutes at 20 °C.

[0101] Step 8) The curd is texturized in water at a ratio of 1 :2 (curd:water) at 80 °C for 3 minutes

[0102] Step 9) The texturized curd is placed in a 5 °C cold storage solution (water with 0.1 % lactic acid) for 12 hours. The result is a firm white spherical mozzarella-like product with small filaments, a moisture content of about 50 weight% and a protein and fat content of 21 weight% and 22 weight%, respectively. The pH is about 4.5. The product can be melted and loses its form completely at temperatures above 120 °C.

[0103] The cheese according to this example is shown in Figure 6.

[0104] Example 4: Using Camel Beta-Casein

[0105] Camel beta-casein (having the amino acid sequence of Figure 10B) was expressed using a recombinant construct comprising the nucleotide sequence of Figure 10 A and used in the following example. An alternative source of the camel beta-casein would be by extraction from camel milk.

[0106] The following processes were conducted using Batch DSP009 having a protein content with 70% (by weight) of recombinant camel beta-casein and using Batch DSP10 having a protein content with 50% (by weight) of recombinant camel betacasein.

[0107] Gelation via pH Adjustment

[0108] 1 ) Solution of 5% (w / w) camel beta-casein

[0109] 2) Addition of predetermined aliquot of acid (0.5 M HCI)

[0110] 3) Mixing and centrifugation

[0111] 4) Measurement of pH in supernatant

[0112] 5) Measurement of protein content in supernatant

[0113] 6) Calculation of soluble protein content

[0114] The results are show in Figure 7.

[0115] Gelation via Calcium ion addition (performed in duplicate)

[0116] 1 ) Solution of 5% (w / w) camel beta-casein

[0117] 2) Addition of aliquot of Calcium Chloride solution (35 % CaCh) to predetermined Ca2+: Protein ratio

[0118] 3) Mixing and centrifugation

[0119] 4) Measurement of pH in supernatant 5) Measurement of protein content in supernatant

[0120] 6) Calculation of soluble protein content

[0121] The results are show in Figure 8.

[0122] Gelation via combination of pH Adjustment and Calcium ion addition (DSP10)

[0123] 1 ) Solution of 5% (w / w) camel beta-casein (Batch DSP10 used)

[0124] 2) Addition of Fat (P:F 1 :1 )

[0125] 3) Emulsification via high-shear or Ultra-Turrax

[0126] 4) pH Adjustment

[0127] 5) Ca2+addition

[0128] 6) Settling of the Gel

[0129] 7) Sieving of the Gel

[0130] 8) Texturization (80 °C to 90 °C)

[0131] The results are show in Figure 9.

[0132] Results

[0133] Combination of pH & Ca2+

[0134] Lowest solubility achieved at pH of approximately 5.3 - see Figure 7.

[0135] Ca2+addition led to precipitation starting at 0.2-0.3 mMol Ca2+ / g beta-casein - see Figure 8.

[0136] The protein gels obtained for batch DSP010 are shown in Figure 9.

[0137] Gelation

[0138] Good gelation and formation of a solid gel was obtained using the combination of acid and calcium using batch DSP10 for camel beta-casein.

Claims

CLAIMS1 . A process of forming a fibrous cheese product, wherein said process comprises providing a protein component, wherein said protein component has a protein content of at least 50% by weight beta-casein, followed by at least one of the following steps to form a treated component: i) addition of a calcium salt, and / or ii) adjusting the pH to a pH of 4 to 8.

2. The process as claimed in claim 1 wherein said protein component is an aqueous solution of beta-casein.

3. The process as claimed in claim 2 wherein the aqueous solution is admixed with a fat to form an emulsion prior to the acidification step and / or before the addition of calcium salt.

4. The process as claimed in claim 2 or claim 3 wherein said aqueous solution comprises up to 20% by weight of beta-casein.

5. The process as claimed in any one of claims 2 to 4, wherein said emulsion or aqueous solution is cooled to a temperature below ambient for a period of up to 10 minutes.

6. The process as claimed in claim 5 wherein said emulsion or aqueous solution is cooled to a temperature below 10°C.

7. The process as claimed in claims 3 to 6 wherein said emulsification step occurs at a temperature of from 5°C to 25°C.

8. The process as claimed in claim 2 to 7 wherein the pH of said emulsion or aqueous solution is acidified to a pH of 4.0 to 8.0 to form the treated component.

9. The process as claimed in claim 8 wherein hydrogen chloride, lactic acid, citric acid, D-(+)-glucono-delta-lactone and / or acetic acid are used for acidification of said emulsion or aqueous solution.

10. The process as claimed in claim 8 wherein a bacterial starter culture is used for acidification of said emulsion or aqueous solution.11 . The process as claimed in any one of claims 1 to 10 wherein said acidification step is conducted at a temperature of 5 to 10°C.

12. The process as claimed in any one of claims 3 to 11 wherein a calcium salt is added prior to or during the emulsification step.

13. The process as claimed in claim 12 wherein said emulsion or aqueous solution is treated by addition of a calcium salt to form said treated component.

14. The process as claimed in claim 13 wherein the said addition of the calcium salt to the emulsion or aqueous solution occurs at temperature of 5 to 10°C.

15. The process as claimed in any one of claims 12 to 14 wherein said calcium salt is added in an amount of 0.2 to 2 mmol I g protein.

16. The process as claimed in any one of claims 12 to 15 wherein said calcium salt is calcium chloride, calcium hydroxide, calcium carbonate, calcium citrate, calcium phosphate, stearate malate, calcium glycerophosphate, calcium lactate, calcium gluconate or mixtures thereof.

17. The process as claimed in claim 16 wherein said calcium salt is calcium chloride.

18. The process as claimed in any one of claims 1 to 12 wherein the addition of a calcium salt occurs prior to the acidification step.

19. The process as claimed in any one of claims 1 to 17 wherein an addition of a calcium salt occurs after the acidification step.

20. The process as claimed in any one of claims 1 to 19 wherein at least one of the following processing steps is conducted after formation of said treated component: a) incubation of the admixture, with regular cutting; and / or b) whey drainage; and / or c) plasticization and forming to produce a cheese product; and / or d) cooling the cheese product.21 . The process as claimed in claim 20 wherein all of the following processing steps are conducted after formation of said treated component: a) incubation of the admixture, with regular cutting; and / or b) whey drainage; and / or c) plasticization and forming to produce a cheese product; and / or d) cooling the cheese product.

22. The process as claimed in any one of claims 1 to 21 wherein said beta-casein is camel beta-casein.

23. A fibrous cheese product formed using the process as claimed in any one of claims 1 to 22.

24. The fibrous cheese product as claimed in claim 23 which is a mozzarella-style cheese product.

25. The fibrous cheese product as claimed in either one of claims 23 and 24 which comprises a moisture content of at least 50% by weight.

26. A fibrous cheese product which comprises at least 15% by weight [3 casein.

27. The fibrous cheese product as claimed in claim 26 which is a mozzarella-style cheese product.2228. The fibrous cheese product as claimed in either one of claims 26 and 27 which comprises a moisture content of at least 50% by weight.

29. The fibrous cheese product as claimed in any one of claims 23 to 28 formed using camel-beta-casein.

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