WO2020115012A1

WO2020115012A1 - Preparation of pasta filata cheese precursor and pasta filata cheese

Info

Publication number: WO2020115012A1
Application number: PCT/EP2019/083408
Authority: WO
Inventors: Johannes Antonius Penders; Thom HUPPERTZ; Tom VAN HENGSTUM; Mohit HANS
Original assignee: Frieslandcampina Nederland B.V.
Priority date: 2018-12-03
Filing date: 2019-12-03
Publication date: 2020-06-11
Also published as: EP3890498A1

Abstract

Process for making a pasta filata cheese precursor comprising the steps of a. providing a pre-cheese comprising, based on the weight of the pre-cheese, 10-36 wt.% of protein comprising, based on total weight of protein, at least 50 wt.% of casein which casein is provided by a casein source that contains, based on dry matter, 60 wt.% or more of casein; 10-36 wt.% of fat provided by a fat source selected from anhydrous milk fat, an anhydrous milk fat fraction, butter, butter oil, cream having a fat content, based on total weight of cream, in the range of 30 to 80% by weight, and mixtures of two or more of these; b. mixing a coagulant and acidifier into the pre-cheese; and c. allowing the pre-cheese to coagulate and acidify to obtain the pasta filata cheese precursor having a pH in the range of 4.8 to 5.7. The pasta filata cheese precursor obtained can be further processed into a pasta filata cheese.

Description

Title: Preparation of pasta filata cheese precursor and pasta filata cheese

FIELD OF THE INVENTION

The invention relates to a process for making a pasta filata cheese precursor and pasta filata cheese, to the pasta filata cheese precursor and pasta filata cheese obtainable by such process and to the use of certain casein sources to make the pasta filata cheese precursor and pasta filata cheese.

BACKGROUND TO THE INVENTION

Dairy products are made from mammalian milk and therefore are considered healthy and nutritious. Cheeses are amongst such dairy products and this invention is about pasta filata type cheeses, such as mozzarella, but also about pasta filata cheese precursors. Such precursors can be further processed to manufacture pasta filata type cheese, but could also be processed to pizza cheese. Hence, pasta filata cheese precursors can be regarded as a separate product. Cagliata cheese is the most prominent example of a pasta filata cheese precursor. It is a soft cheese with a soft texture and creamy, somewhat lactic flavor.

Mozzarella is a well known pasta filata cheese made from milk from either cows or buffaloes. It is a smooth, elastic cheese with a protein structure consisting of long stranded parallel- oriented protein chains. It is a white, rindless cheese. Mozzarella is typically prepared by so called“pasta filata” processing, which consists of heating curd of a suitable pH value followed by kneading and stretching the curd until it is smooth. The warm curd is subsequently cut and moulded into the desired shape and finally firmed by cooling. CODEX standard 262-2006 describes the requirements and characteristics of typical mozzarella cheese. Examples of other pasta filata cheeses are burrata, provolone and scamorza.

The past decades have seen proposals for changes to the manufacturing process of cheese. At the same time, though, it can easily be imagined that manufacturers are reluctant to consider any changes for fear of jeopardizing their product’s qualities, such as texture and taste. One proposal for change is coagulating milk protein- containing compositions from which a portion of the water and sometimes also the whey proteins have been removed by microfiltration. Starting from milk one prepares a retentate, or concentrated composition, that is used to make a“pre-cheese” which is directly converted into cheese without laborious and costly separation steps to recover the curd.

WO 98/10661 A describes such a cheese making method utilizing two distinct acid-forming fermentation steps. Cheese milk is microfiltered, partially fermented, evaporated, and further fermented and coagulated.

Another such method is described in WO 2012/110706 A which teaches to microfilter raw milk, preacidify it, and evaporate the pre-acidified casein concentrate to produce a so-called“pre-cheese” which is then processed to the cheese product. In this publication it is explained that the pre-acidification is necessary to reduce, or restrain increase of, the viscosity of the casein-containing streams. The reason for this undoubtedly is that the casein-containing streams still contain all the ingredients of the raw milk including the milk fat or - after partial skimming— part of the milk fat.

This pre-acidification in the process of WO 2012/110706 A, however, is disadvantageous because it entails the risk of premature coagulation, given the inherent variability of starter cultures in case starter cultures are used, and the risk of local over-acidification and coagulation in case chemical acidification is used. Another disadvantage of this prior art process is that the fat content of the final cheese product is necessarily related to the extent of skimming of the raw milk material that is subjected to microfiltration. These factors make that the process of WO 2012/110706 A is cumbersome.

US 2016/0100600 Al discloses a process for the preparation of a cheese having spreading and/or ropy properties, such as mozzarella cheese, from a milk protein concentrate. Water, fat and the milk protein concentrate are mixed by a solid-liquid mixer at high stirring speed at elevated temperature. The resulting base composition then is deaerated under vacuum to obtain a homogenous pre cheese mix. This pre-cheese mix is cooled, coagulated, textured by adding steam or hot water at elevated temperature and finally moulded and/or unmoulded. A key feature is that no whey is separated after coagulation. This method is rather cumbersome in that it requires a deaeration step under vacuum in order to obtain a suitable pre-cheese mix for further processing into a mozzarella cheese.

The present invention aims to provide a process for preparing pasta filata cheese precursors and pasta filata cheeses with no or anyhow limited whey separation and whey purification steps, which process does not have the disadvantages associated with the processes described in WO 2012/110706 A and US 2016/0100600 Al.

SUMMARY OF THE INVENTION

The crux of the invention lies in a two-fold finding. One is that the inventors found that for cheese making it is possible to use casein sources made by membrane filtration of skimmed milk that contains no or only a very small amount of fat. As a result, viscosity levels during the preparation of these casein sources remain low and concentrated casein-containing streams made therefrom need not be pre-acidified and can be handled easily. The other finding is that this casein source can be combined with different types of fat sources. Accordingly, the fat source that could be used in the process according to the present invention is fat that has been isolated from its natural environment and has undergone one or more processing steps, such as fractionation, dehydration, homogenization and/or pasteurization. In milk fat sources such as, for example, anhydrous milk fat and butter, the fat no longer possesses the globule membrane that surrounds them in natural milk. Such globule membrane, on the other hand, is still intact in fat that is present in cream isolated from whole milk. Such cream can also be used as the fat source.

It has surprisingly been found that cheese making from these casein and fat sources does not impair the quality of the cheeses when made in accordance with the process according to the present invention.

Accordingly, the present invention relates to a process for making a pasta filata cheese precursor starting from a protein concentrate and a fat source from which a pre-cheese is made, which pre-cheese is subsequently acidified and coagulated. The resulting pasta filata cheese precursor can be further processed into a pasta filata cheese.

DETAILED DESCRIPTION OF THE INVENTION

More specifically, the present invention relates to a process for making a pasta filata cheese precursor comprising the steps of

a) providing a pre-cheese comprising, based on the weight of the pre-cheese,

10-36 wt.% of protein comprising, based on total weight of protein, at least 50 wt.% of casein, which casein is provided by a casein source that contains, based on dry matter, 60 wt.% or more of casein;

10-36 wt.% of fat provided by a fat source selected from anhydrous milk fat, an anhydrous milk fat fraction, butter, butter oil, cream having a fat content, based on total weight of cream, in the range of 30 to 80% by weight, and mixtures of two or more of these;

b) mixing a coagulant and acidifier into the pre-cheese; and

c) allowing the pre-cheese to coagulate and acidify to obtain the pasta filata cheese precursor having a pH in the range of 4.8 to 5.7.

In the context of the invention, the term“pre-cheese” refers to the mixture that is prepared by combining the sources of casein and fat and optional additives. Any acidifiers or coagulants are not included. Hence, the pre-cheese will contain casein, fat, water, small amounts of components such as whey protein, lactose salts, and optionally other components, such as flavor enhancing additives, and starches.

The protein used to make the pre-cheese must contain at least 50 wt% of casein. Other proteins, such as whey protein or plant-based protein, may be present too. It is preferred that, based on the total weight of protein in the pre cheese, at least 60 wt.% is in the form of casein, more preferably at least 70 wt.%. The casein may come from bovine milk, buffalo milk, goat milk or sheep milk, preferably from bovine milk. Generally, the casein is provided by a casein source that can be prepared from skimmed milk, semi- skimmed milk or whole milk using filtration processes known in the art. Although the protein used may, in addition to the casein source, comprise additional protein sources (e.g. casein-lean or casein- free protein sources such as plant-based proteins or whey proteins), it is preferred that all protein used comes from one or more casein sources and that no other (casein-lean or casein-free) protein sources are used. Any general reference to “casein source” used herein refers to a protein source that is rich or enriched in casein and contains, based on dry matter, 60 wt.% or more of casein. Such casein source may contain other proteins, in particular whey proteins, as explained in more detail below.

Suitable casein sources are commercially available and include products that are known as micellar casein isolate (MCI) and milk protein concentrate (MPC), but other names are also used, such as micellar casein concentrate, microfiltered milk protein concentrate, phosphocaseinate and native phosphocaseinate. In addition, Huppertz et ah, International Dairy Journal, 74, pp. 1-11 (2017) teach that casein micelles may be formed from sodium caseinate.

The casein source may contain whey protein in a caseimwhey protein weight ratio of about 4:1— as in raw milk - or higher. Preferred casein sources contain casein and whey protein in an amount such that the caseimwhey protein weight ratio is 8:1 or higher. MPC belongs to the former, MCI to both the former and the latter. MCI products are preferred casein sources.

The content of casein in the casein source is 60 wt.% or higher, based on total weight of dry weight matter in the casein source, preferably at least 70 wt.%. Very good results have been achieved with casein sources having a casein content between 70 and 85 wt% of casein, based on total weight of dry matter. For example, if the casein source is in powdered form, it will be used in the present process in the form of a suspension in an aqueous medium, suitably water. To this end, the powder can be suspended in water (or some other aqueous medium such as a suitable salt solution) and the suspension can subsequently be evaporated until the suspension has reached the required protein and casein content for further processing into the pre-cheese. Such concentration can take place without the need for acidification such as taught in prior art teachings such as aforementioned WO 2012/110706 A. Another possibility is to start from an aqueous protein (with high casein content) suspension having a protein content of less than 20 wt.% based on total weight of the suspension and then add powdered casein source to reach the desired protein and casein content.

The fat source used in the process of the invention to provide the fat component in the pre-cheese is selected from anhydrous milk fat (AMF), an anhydrous milk fat fraction made from anhydrous milk fat, butter, butter oil, cream having a fat content, based on total weight of cream, in the range of 30 to 80% by weight, and mixtures of two or more of these. The dairy-based fats may come from bovine milk, buffalo milk, sheep milk or goat milk, bovine milk being preferred. The preferred fat sources are cream derived from cows’ milk having the fat content indicated above and AMF isolated from bovine milk.

The cream used as the fat source has a fat content, based on total weight of cream, in the range of 30 to 80% by weight, preferably 35 to 77% by weight, more preferably 38 to 74% by weight. In one embodiment cream having a fat content in the range of 40 to 55% by weight could suitably be used. In another embodiment cream with higher fat contents, such as in the range of 55 to 74% by weight, could be used. The cream is suitably derived from cows’ milk by separating the cream from the whole milk by ways known in the art. Generally, cream can be separated from whole milk by spontaneous skimming, based on spontaneous creaming, or by centrifugal skimming technologies. If needed, the cream can be standardized to the desired fat content. Before use the cream is suitably pasteurized.

Fractions made from AMF are known. See, for instance, Van Aken et al., JAOCS 76, no. 11, 1323-1331 (1999). Which fraction to use for the process according to the invention will depend on the properties of the pasta filata cheese precursor or pasta filata cheese one eventually wishes to make.

Next to the protein and the fat, the pasta filata cheese precursor may be provided with other desirable components such as polysaccharides (e.g. starches), flavors, colorants, herbs, spices, vitamins, and salts.

In step (a) of the process according to the invention the pre-cheese is provided. This can be achieved in different ways as will be apparent to the skilled person. Accordingly, step (a) of the present process suitably comprises the steps of (i) providing an aqueous suspension of the protein (i.e. the casein-rich protein as described above), preferably a suspension of a casein source which comprises, based on dry matter, at least at least 60 wt.%, more preferably at least 70 wt.% and most preferably between 70 and 85 wt.%, of casein;

(ii) heating the aqueous suspension obtained in step (i) to a temperature above the melting temperature of the fat source to be used in step (iii);

(iii) preparing a fat-in- water emulsion by

A. adding the fat source (i.e. the fat source as described above);

B. optionally adding additional protein of a casein source (i.e. casein-rich protein), preferably the same casein source as used in step (i), either separate from or simultaneously with the fat source; and

C. emulsifying the mixture into a fat-in-water emulsion;

in any order provided step (iii) C always takes place after step (iii) A; and

(iv) cooling the fat-in-water emulsion to obtain the pre-cheese.

In steps (i) and (iii) the different components are obviously added in such amounts as to arrive at the required contents of protein, casein and fat in the pre cheese as defined herein, i.e. in the range of 10 to 36 wt.% of protein comprising, based on total weight of protein, at least 50 wt.% of casein, and in the range of 10 to 36 wt.% of appropriate fat, the weight percentages for protein and fat being based on total weight of the pre-cheese. Step (ii) could also be carried out after addition of the fat source in step (iii). In such a case the fat source, if not cream or butter oil, is suitably added in the form of small pieces, so that it melts more easily when the temperature of the mixture is raised to above its melting temperature. In case of cream or butter oil as the fat source, pre-cutting the fat source in small pieces is obviously not needed, as such fat source is already in a form that can be easily processed.

When starting from a casein-rich protein powder in step (i), such as a MPC or MCI powder, suitable aqueous protein suspensions can be obtained by mixing appropriate amounts of such protein powder and water (or a suitable aqueous salt solution) until the protein suspension is obtained, optionally including one or more concentration steps as described below. When starting in step (i) from an aqueous casein-rich protein suspension having a total solids content of 20 wt.% or less (based on total weight of suspension), such as for example 15 to 20 wt.%, suitable aqueous protein suspensions can be obtained by subjecting the low solids content- suspension to one or more concentration steps. Such concentration steps could typically involve one or more evaporation steps, filtration steps or the addition of a highly concentrated casein-rich protein suspension or even casein-rich protein powder. A combination of two or more of these steps is also feasible.

The casein-rich protein that is optionally added in step (iii)B can be added as a suspension or as a powder. It is, however, preferred to add the casein-rich protein in this step as a powder. It is preferred that this casein-rich protein is the same casein source that is used in step (i). As indicated, a particularly preferred casein source is MCI. Emulsification in step (iii)C can take place by methods known in the art and may depend on the fat source used. For example, if cream is used as the fat source, simple mixing in the cream will suffice, as cream is already an emulsion. In the case of AMF, on the other hand, the fat needs to be broken down into small globules to form an emulsion, thus requiring more rigorous mixing and imparting more shear forces (i.e. high shear mixing).

For example, in one suitable embodiment the pre-cheese is made by the successive steps of

(i) providing a suspension of the protein in water having a total solids content in the range of 25 to 45 wt.%, preferably 27 to 43 wt.%, most preferably 28 to 41 wt%;

(ii) heating the suspension to a temperature above the melting temperature of the fat source;

(iii) A. adding the fat source, suitably in liquid form, to the heated suspension;

C. mixing the fat source and the suspension to obtain a fat-in- water emulsion; and

(iv) cooling the fat-in-water emulsion to obtain the pre-cheese.

In another exemplary embodiment step (a) comprises the successive steps of

(i) providing a suspension of the protein in water having a total solids content below 25 wt.%;

(ii) heating the suspension to a temperature above the melting temperature of the fat; (iii) A. adding the fat source, suitably in liquid form, to the heated suspension;

C. mixing the fat source and the suspension to obtain a fat-in- water emulsion;

B. adding casein-rich protein whilst mixing, in such amount to obtain a fat- in- water emulsion having a total solids content in the range of 25 to 45 wt.%, preferably 27 to 43 wt.%, most preferably 28 to 41 wt%; and

(iv) cooling the resulting fat-in-water emulsion to obtain the pre-cheese.

In yet another embodiment step (a) comprises the successive steps of

(iii) A./B. suspend casein-rich protein powder in the liquid fat source and adding the resulting protein-in-fat suspension to the heated protein suspension resulting from step (ii);

C. mixing to obtain a fat-in- water emulsion having a total solids content in the range of 25 to 45 wt.% .%, preferably 27 to 43 wt.%, most preferably 28 to 41 wt%; and

(iv) cooling the resulting fat-in-water emulsion to obtain the pre-cheese.

In case cream is used as the fat source, step (a) suitably further comprises at least one evaporation step to remove water. In the different embodiments described above, this implies that such evaporation step(s) would typically be applied after step (iii) and prior to step (iv), i.e. directly after the protein source and cream are mixed and the fat-in- water emulsion is formed.

As illustrated by the different embodiments described above, preparation of the pre-cheese suitably starts from an aqueous suspension of the casein-rich protein source as also indicated above. Suitable protein sources have been described hereinbefore. Many commercial MPC and MCI products are available as powders with low water content (i.e. less than 10 wt.% on total weight of powder). Such powders could suitably be used for providing the aqueous protein suspension in step (i). Alternatively, aqueous protein suspensions with a total solids content of less than 20 wt.%, suitably in the order of 15-20 wt%, based on total weight of the suspension could be used as starting material. Such suspension would typically be obtained after membrane filtration in a process for preparing MPC or MCI powder. For the purpose of the present invention it was found particularly suitable to use a suspension of the protein in water having a total solids content in the range of 25 to 45 wt.%, preferably 27 to 43 wt.%, most preferably 28 to 41 wt%, based on total weight of the suspension. Use of such a suspension allows easy incorporation into the mixture of the fat. It was found that simple high shear mixing of the fat into the casein-containing suspension suffices to arrive at a pre cheese that has an adequate consistency and stability to be processed to the final cheese product in accordance with the invention. This consistency can be described as a thick, viscous yet pumpable mass. When starting from a MPC or MCI powder, suitable protein suspensions are obtained by mixing appropriate amounts of such protein powder and water (or a suitable aqueous salt solution) until the protein suspension is obtained, optionally including one or more concentration steps as described below. When starting from an aqueous casein-rich protein suspension having a total solids content of 20 wt.% or less (based on total weight of suspension), suitably 15 to 20 wt.%, suitable suspensions of the protein in water for preparing the pre-cheese can be obtained by subjecting such suspension to one or more concentration steps. Such concentration steps could typically involve one or more evaporation steps, filtration steps or the addition of a highly concentrated casein-rich protein suspension or even casein-rich protein powder. A combination of two or more of these steps is also feasible.

The protein suspension is heated to a temperature above the melting temperature of the fat that is subsequently added whilst stirring or otherwise imparting shear to the mixture. The fat source is preferably added in liquid form, so that it can be effectively mixed into the suspension to obtain a fat-in-water emulsion. In the case cream is used as the fat source, the cream will suitably first be heated to a temperature above the melting temperature of the fat in the cream, thereby enabling effective mixing into the suspension to obtain the fat-in-water emulsion. However, such pre-heating of the cream is not strictly necessary, as the cream is already a fat-in- water emulsion, so that effective mixing with the heated protein suspension can be achieved. The fat may also be added in solid form. In that case the fat will first be allowed to melt in the protein suspension before the melted fat is effectively mixed and a fat-in-water emulsion is obtained. Cooling of this emulsion then yields the pre-cheese. Cooling may take place to a temperature below the melting temperature of the fat used, so that the fat particles solidify in the emulsion before acidification and coagulation takes place. However, this not necessarily need to be the case. For example, when using milk fat fractions as the fat source, the melting temperature of such fat fractions may be lower than the temperature to which the pre-cheese is cooled. The actual temperature to which the emulsion is cooled is a temperature at which the subsequent step of acidification and coagulation suitably takes place. It was found that a temperature in the range of from 10 to 50 °C, more preferably 20 to 40 °C, is a suitable target temperature of the pre-cheese. Further processing of the pasta filata cheese precursor also suitably takes place within this temperature range.

The pre-cheese comprises 10-36 wt.% of protein and 10-36 wt.% of fat provided by a fat source selected from anhydrous milk fat, an anhydrous milk fat fraction, butter, butter oil, cream having a fat content, based on total weight of cream, in the range of 30 to 80% by weight, and mixtures of two or more of these. Preferred amounts are 15-35 wt.%, more preferably 20-30 wt.%, of the protein and 12-30 wt.%, of the fat. These weight percentages are based on the weight of the pre-cheese. It is to be understood that these percentages relate to the weight of the actual components themselves. For instance, when using butter as the fat source, one introduces both water and fat, and in such a case it is only fat that is to be attributed to the fat percentage, not also the water. The same applies when using cream as the fat source.

In step (b) of the present process a coagulant and acidifier are added to and mixed into the pre-cheese. Suitable coagulants and acidifiers for use in preparing pasta filata type cheeses are well known. Target pH of the pasta filata precursor and hence target pH after completion of the coagulation and acidification step (c) is typically 4.8 to 5.7, preferably 4.9 to 5.5. Suitable acidifiers for pasta filata type cheeses are well known and include starter cultures (bacterial acidifiers) which convert lactose into lactic acid, acids, acidulants, such as for example Glucono Delta Lactone or GDL, and combinations of two or more of these. The most common starter cultures include thermophilic starters, typically starters by CSK, Chr. Hansen or DuPont. Thermophilic starters by Chr. Hansen include frozen cultures STI-02, STI-03, STI-04, STI-06 and freeze-dried cultures STI-12, STI-13 and STI-14. Mesophilic starters may also be used. The type of acidifier used and the amount in which it is used will depend on the desired pasta filata precursor or pasta filata cheese to be made and the conditions applied.

Suitable coagulants are known in the art and include, for instance, calf rennet, fermentation-produced rennet and microbial rennet. Examples of calf rennet include Kalase produced by CSK and Naturen produced by Chr. Hansen. Examples of fermentation-produced rennet include Fromase by DSM and Milase by CSK. Examples of microbial rennets are Chy-Max by Chr. Hansen and Maxiren by DSM. Other coagulants include pepsin and various proteolytic enzymes of plant origin.

The acidifier and coagulant are added to and mixed with the pre-cheese. Further taste imparting adjunct starters may be added substantially simultaneously with milk-based minerals. Acidifier and coagulant are added in typical amounts of 0.01 to 1.0% by weight each, the exact amount usually depending on the exact type of acidifier/coagulant used. This is, however, well known in the art.

In step (c) the coagulation and acidification take place and the curd or pasta filata precursor product is formed. As described above, after completion of the coagulation and acidification the pH of the pasta filata cheese precursor should be in the range of 4.8 to 5.7, preferably 4.9 to 5.5, in order to obtain a suitable pasta filata cheese precursor. As mentioned before, the present process does not require the customary removal of large amounts of whey following curd formation, which is a major advantage.

The pasta filata precursor obtained after step (c) can be further processed in manners known in the art, with the exception, of course, that the removal of whey is dispensed with. Such pasta filata precursor could be cagliata which is sold as such for further processing into e.g. mozzarella or processed pizza cheese. The present invention also relates to the pasta filata cheese precursor obtainable by the process as described above. It was found that the pasta filata cheese precursor according to the invention has a low phospholipid content. Typically the pasta filata cheese precursor according to the invention has a phospholipid content of 0.5 wt.% or less, suitably 0.3 wt.% or less, based on the weight of the fat. Without wishing to be bound by any particular theory, it is believed that such comparatively low phospholipid content ensures a higher proportion of protein on the interface of the emulsion droplets and, as a result, better incorporation of these droplets in the protein matrix. This is beneficial when using the pasta filata cheese precursor in the preparation of pasta filata cheese: during stretching and kneading of the precursor in such preparation fat loss will be less, whilst oiling-off (i.e. fat loss) during melting of the pasta filata cheese obtained is also reduced.

In a further aspect of the present invention there is provided a process for the preparation of a pasta filata cheese comprising

a. preparing a pasta filata cheese precursor according to the process described above; and

b. processing the pasta filata cheese precursor to the pasta filata cheese.

Processing of the pasta filata cheese precursor produced in the process of the invention to the final pasta filata cheese product can be realized in manners known in the art. Such further processing would typically involve stretching and kneading until the desired consistency is attained. Traditionally this was done manually, but on an industrial scale this would involve suitable equipment. The further processing into pasta filata cheese in step b. could suitably involve cutting the precursor into small pieces. These pieces are subsequently heated, typically to a temperature in the range of 60 to 75 °C, e.g. by putting them in a hot water bath, after which the heated precursor pieces are passed into a stretching and kneading device (e.g. containing two counterrotating spirally wound screws similar to those used in extruders) where the actual stretching and kneading takes place, thus resulting in the pasta filata cheese product. Alternatively, the pasta filata cheese precursor may be passed into a shredder into which also steam is fed, thereby heating the shredded precursor, and immediately passing the heated shredded precursor into stretching and kneading device. The resulting pasta filata cheese produced may be shaped into the desired shape. These techniques are all well- established in the art.

A major advantage of the cheese-making process according to the invention compared to traditional pasta filata-making processes is the fact that removal of whey to isolate the curd is either not needed at all or is limited. In any event, much less whey needs to be drained from the curd than is the case in traditional processes for preparing pasta filata-type cheeses. The traditional processes make the inclusion of water-soluble ingredients into the curd formation process less attractive because such ingredients will also get (partially) lost upon whey removal. The process according to the invention limits the removal of whey significantly, or may even avoid the removal of whey altogether, so that the ingredients that enter the pre-cheese will essentially all end up in the final pasta filata precursor cheese or pasta filata cheese product. This same aspect offers another major attraction of the invention process because in comparison with traditional pasta filata cheese-making no limitations need to be reckoned with in view of the whey quality. In traditional pasta filata cheese making whey is separated from the curd and commercialized, as such or after further processing. As a result, such whey-producing traditional pasta filata cheese making has its limitations in terms of additive use because the additives are likely to also end up in the whey, thus potentially affecting the properties and the value of the whey. Since in the invention process no or only a limited amount of whey is produced, there is no need to reckon with whey quality when it comes to considering additives that are beneficial to the cheese to be made. Hence, when compared to the traditional ways of pasta filata cheese making, the invention process offers vastly increased flexibility in ingredient use.

A further advantage of the process is that, since no or anyhow much less whey needs to be removed, all caseinomacropeptide (CMP) which is released on hydrolysis of kappa-casein by the action of renneting enzymes, is retained in the cheese. In traditional manufacture of pasta filata cheese the CMP would typically end up in the whey stream. Since CMP is of less value than other whey proteins such as a-lactalbumin and b-lactoglobulin, it is beneficial to have this protein retained in the cheese rather than having to remove it from any whey stream. It has been stated hereinbefore that the instant process hardly produces any whey or, in other words, does not produce a substantial whey stream. The exact amount of whey produced may depend on the fat source used. More specifically, if cream is used as the fat source, the amount of whey produced will be slightly higher than in case any of the other specified fat sources is used. In general, the amount of whey separated from the curd will not exceed 1000 grams per kg of curd, i.e. an amount which is negligible when compared to the traditional ways of pasta filata cheese making, where values exceeding 7500 grams of whey per kg of curd are typically observed. Preferably the amount of whey produced does not exceed 800 grams per kg of curd and more preferably would remain below 600 grams per kg of curd. When anhydrous milk fat, an anhydrous milk fat fraction, butter, butter oil or mixtures of two or more of these is used the sole fat source (i.e. no cream is used), the amount of whey produced will in general not exceed 200 grams per kg of curd, more preferably will not exceed 100 grams per kg of curd.

The invention further relates to the use of a casein source containing, based on dry weight, 60 wt.% or more of casein, preferably 70 wt.% or more, to prepare a pasta filata cheese precursor or a pasta filata cheese.

The invention is further illustrated by the following examples without limiting the scope of the invention to these specific embodiments.

EXAMPLES

Example 1: Preparation of concentrated MCI suspension

The starting material was twenty liters of a suspension of micellar casein isolate (MCI) in water. The suspension contained ~17 wt.% dry matter and the dry matter consisted of ~88 wt.% protein. More than 90 wt.% of this protein (based on total weight of protein) was casein. The pH of the suspension was 6.25. The suspension was evaporated using a rotary evaporator at a temperature of 60°C and at a pressure of 5.0 kPa (50 mbar). After evaporation the solids content of the suspension was 32 wt.%, and its viscosity was 0.275 Pa.s. measured at a shear rate of 794 s ¹ and a temperature of 50 °C using a AR2000 rheometer (TA Instruments USA). The pH of the evaporated suspension was 6.2. Example 2: Preparation of pre-cheese

1000 grams of the suspension prepared in Example 1 were heated to 50 °C. 310 grams of anhydrous milk fat (AMF) which had previously been heated to 50 °C were added. During addition of the AMF, a rotor-stator high-shear mixer was inserted in the blend and was run at 3000 rpm for 7 minutes. Particle size analysis was conducted after 7 min of shearing by means of static light scattering using a Malvern Mastersizer 2000. The surface weighted mean diameter (D3,2) was determined to be 0.00158 mm. Microscopic analysis of the sample indicated a fat-in-water emulsion. This pre-cheese was cooled to 30 °C and contained 20 wt.% of casein, 24 wt.% of AMF, 4.2 wt.% of solids not being casein and AMF, and the remainder water.

Example 3: Preparation of paste filata cheese precursor

800 grams of the pre-cheese prepared in Example 2 was placed in a container and held at 30 °C. Rennet (Kalase, ex CSK Food Enrichment, The Netherlands) was added at a concentration of 0.125 mg/kg. In addition, starter culture (C56, ex CSK Food Enrichment, The Netherlands) was added in an amount of 1 ml/kg. The resulting sample was subsequently incubated at a temperature of 30 °C and allowed to coagulate. Table 1 below shows the pH measured at the start of the coagulation and acidification (at 0 hours), after 4 hours and after 20 hours. When the sample reached a pH of 5.20 after 20 hours, it was cooled to 4 °C to obtain the pasta filata cheese precursor.

Table 1 - pH

Phosholipid content of the pasta filata cheese precursor was determined to be 114 mg per 100 grams of pasta filata cheese precursor corresponding with 0.48 wt.% based on total weight of fat. Example 4: Preparation of paste filata cheese

The pasta filata cheese precursor prepared in Example 3 was heated to a temperature between 60 and 75 °C. It was subsequently kneaded and stretched by hand for at most two minutes and cooled to 4 °C to obtain the pasta filata cheese.

Example 5: Preparation of concentrated MCI suspension

The starting material was 1000 liters of a suspension of micellar casein isolate (MCI) in water. The suspension contained ~17 wt.% dry matter and the dry matter consisted of ~88 wt.% protein. More than 90 wt.% of this protein (based on total weight of protein) was casein. The pH of the suspension was 6.3. The suspension was warmed up to 74 °C, held at this temperature for at least 20 seconds, followed using a 4-stage falling-film evaporator at 60 °C. After evaporation the solids content of the suspension was 29 wt.%. The pH of the evaporated suspension was 6.2.

Example 6: Preparation of pre-cheese

641 grams of the suspension prepared in Example 5 were heated to 60 °C. 358 grams of cream (with a fat content of 42 wt.%) which had previously been heated to 50 °C, were added and the blend was mixed for 2 minutes. The resulting pre-cheese was cooled to 40 °C and contained 17.5 wt.% of protein, 14.6 wt.% of fat, 3.5 wt.% of solids not being protein and fat, and the remainder water.

Example 7: Preparation of paste filata cheese precursor

1 kilograms of the pre-cheese prepared in Example 6 was placed in a container and held at 30 °C. (Milase Premium, ex CSK Food Enrichment, The Netherlands) was added at a concentration of 0.0375% (m/m). In addition, starter culture STW6 (Chr. Hansen, DK) was added in an amount of 0.075 % (m/m). The resulting sample was subsequently incubated at a temperature of 30 °C and allowed to coagulate.

After 4 hours of coagulation the mass was cut into blocks of 0.8 cm x 0.8 cm x 0.8 cm and these were spread on surface and allowed to drain at 40 °C for 4 hours, where a weight loss of 35% based on weight of the original mass was realized (corresponding with whey stream of about 540 g/kg curd). During coagulation pH was measured; 8 hours after addition of starter culture the pH was 5.4. The drained curd was subsequently placed in plastic bags and vacuum packaged and stored at 4 °C for 12 hours.

Example 8: Preparation of paste filata cheese (cooker stretcher)

25 kg of a vacuumed pasta filata cheese precursor prepared in Example 7 was placed in a waterbath at 82 °C for 8 minutes. A product temperature of 63 °C was reached after this time. The cheese was then placed into a steam cooker (Almac FV 100, Almac S.r.L, Modena), operated at a temperature between 60 and 65°C, for 10 minutes. During this process, 1% m/m NaCl was added. The stretched product was put into containers, then cooled to 4 °C and stored at this temperature. The final pasta filata cheese product contained 49 wt% moisture, 23 wt% fat and 25 wt% protein.

Example 9: determination of functional properties of pasta filata cheese

After storage for 14 days at 4 °C, the pasta filata cheese of Example 8 was tested for flowability. Flowability was determined using the Schreiber test, the principle of which is described in Kosikowski, F., Cheese and Fermented Milk Foods, F. V. Kosikowski & Assoc., Brooktondale, NY, 1977, Pages 337-340.

Accordingly, a piece of cheese was cut out slowly to prevent deformation, with a cheese borer (0=4Omm) out of a slice of cheese ± 40 mm. This cylindrical piece of cheese was cut in a symmetrical way to 20 mm height with a wire of 0.6 mm thick. These samples were weighed and wrapped in aluminum foil for at least 30 minutes at 4-7 °C. The sample was located in the center of Schreiber form which was placed on a tray, and afterwards heated in an oven at 150 °C for 15 minutes. The form with sample was removed from the baking tray and Schreiber score was determined on 8 points which were averaged, and the flow was expressed as the increase in surface area in cm². Flowability was determined to be 49 cm² which is considered to be a good performance.

Claims

1. A process for making a pasta filata cheese precursor comprising the steps of

(a) providing a pre-cheese comprising, based on the weight of the pre-cheese,

(b) mixing a coagulant and acidifier into the pre-cheese; and

(c) allowing the pre-cheese to coagulate and acidify to obtain the pasta filata cheese precursor having a pH in the range of 4.8 to 5.7.

2. Process according to claim 1, wherein the protein comprises, based on total weight of protein, at least 60 wt%, preferably at least 70 wt.%, of casein.

3. Process according to claim 1 or 2, wherein the fat source is anhydrous milk fat or cream.

4. Process according to any one of claims 1 to 3 wherein step (a) comprises the steps of

(i) providing an aqueous suspension of the protein;

(iii) preparing a fat-in- water emulsion by

A. adding the fat source;

B. optionally adding additional protein, either separate from or simultaneously with the fat source; and

C. emulsifying the mixture into a fat-in-water emulsion;

in any order provided step (iii) C always takes place after step (iii)A; and

(iv) cooling the fat-in-water emulsion to obtain the pre-cheese.

5. Process according to claim 4, wherein step (i) comprises subjecting an aqueous suspension of the protein having a total solids content, based on total weight of suspension, of 20 wt.% or less to one or more concentration steps.

6. Pasta filata cheese precursor obtainable by the process according to any one of claims 1-5.

7. Pasta filata cheese precursor according to claim 6, which has a phospholipid content of 0.5 wt.% or less based on the weight of the fat.

8. Process for the preparation of a pasta filata cheese comprising a. preparing a pasta filata cheese precursor according to the process of any one of claims 1-5; and

b. processing the pasta filata cheese precursor to the pasta filata cheese.

9. Use of a protein source containing, based on dry weight, 60 wt.% or more of casein in the preparation of a pasta filata cheese precursor or pasta filata cheese.