EP1746900A1

EP1746900A1 - Fresh cheese of plastic, homogenised texture and method and apparatus for the manufacture thereof

Info

Publication number: EP1746900A1
Application number: EP05734167A
Authority: EP
Inventors: Péter Horváth; R Bert Mezriczky
Original assignee: Gervais Danone SA
Current assignee: Gervais Danone SA
Priority date: 2004-04-13
Filing date: 2005-04-13
Publication date: 2007-01-31
Also published as: WO2005099470A1; HUP0400763A2; HU0400763D0

Abstract

The present invention relates to a method of producing acid-coagulated, fermented, fresh cheese with an extrudable and homogeneous texture comprising cutting, heating, pressing and agitating a fermented curd prepared from skimmed, homogenised and heat-treated milk, wherein the pressed curd is subjected to intensive high-shear agitation in a non-pressure-tight container equipped with a cutting and blending device until reaching a substantially homogeneous texture, and, after cooling, the temperature is adjusted to avoid damage to fresh cheese. In addition, the present invention relates to acid-coagulated, fermented fresh cheese of plastic and homogeneous texture, which is preferably of the curd cheese type, to a fresh cheese preparation comprising it, and to a dairy dessert produced using any of the above. Preferably, the dairy dessert of the present invention is flavoured and enrobed. Furthermore, the present invention relates to an apparatus of batch operation, particularly designed to cut and blend food materials of soft consistency.

Description

Fresh cheese of plastic, homogenised texture and method and apparatus for the manufacture thereof

1. Field of the Invention The present invention pertains to the field of dairy products, specifically to the field of cheesemaking. The present invention relates to a method of producing acid-coagulated, fermented, fresh cheese with an extrudable and homogeneous texture, to acid-coagulated, fermented, fresh cheese with an extrudable and homogeneous texture, which is preferably of the curd cheese type, to a fresh cheese preparation comprising it, and to a dairy dessert produced using any of the above. Furthermore, the present invention relates to an apparatus of batch operation, particularly designed to cut and blend food materials of soft consistency. 2. Background Art Dairy desserts produced of protein concentrates of milk origin- are becoming increasingly popular world-wide, as well as in Hungary. As far as nutritional facts are concerned, the most valuable products include desserts made of fresh cheese. Such products are tasteful, have high protein and vitamin levels and do not induce obesity. One type of dessert made of fresh cheese is produced by e-xtruding the fresh cheese or a mass prepared therefrom, cutting the extruded material and, in several cases, enrobing it. Therefore, in addition to having a favourable taste, aesthetic appearance, appropriate shelf-life and nutritional value, the substance of the cheese material in such products should comply with the following criteria: (i) stability of shape combined with plasticity, i.e., it should be plastic, and (ii) texture (consistency), which is attractive and acceptable for consumers. In the case of fresh cheese preparations, simultaneous compliance with these criteria has been a major problem in several prior art processes. EP 0866658 (UNILEVER N.N.) describes a method comprising heating a mixture of soured cream and acid-coagulated curd, and, upon separation from the whey, homogenising it at a pressure of 30 to 400 bar. The resulting product is a cream- with a solids content of 27% to 35%, which has a softer consistency than the extrudable preparations, and can be filled into containers. US 5,250,316 describes a method for the preparation of a homogeneous dispersion containing ricotta cheese, comprising stirring a mixture of hot water, gelatine, a binder and starch under high shearing stress until gelation of the starch occurs, adding ricotta cheese and further stirring the mixture. Then, the resulting mixture is cast into moulds at room temperature. FR 2639796 (Woestyne, Francoise van de) describes a method of preparing a dessert from fresh cheese (fromage frais) with chocolate coating. The method comprises preparing individual pieces of fresh cheese in moulds, removing the cheese pieces to spread sugar on the surface thereof, cold-storing until reaching a solids content of at least 30%, and finally enrobing the resulting product. Several solutions have been known to prepare products with creamy texture that is still extrudable. However, this includes expanding (increasing the volume of) the cheese material, preferably by an inert gas. US 5,194,283 (Nestec S.A.) describes coextrusion of non-heat-treated curds of different textures. The curd functioning as the inside filling is expanded by nitrogen gas until an increase of volume by 80%. EP 0714608 (Unilever N.N.) describes a method comprising mixing soft cheese and additives to prepare a dessert filling, cooling the mixture to -2°C in a scraped surface heat exchanger and finally expanding it by nitrogen gas until an overrun of 20% to 60% in a closed system, at 240 φm. Upon extrusion, the filling is immediately cooled, preferably to -30°C, and then cut to size and enrobed. The starting soft cheese is not defined. In Hungary, enrobed (coated) dairy desserts based on Hungarian curd cheese ("tύrό"), which are produced by extrusion, are highly popular. The characteristic clumpy and particulate structure and texture of such products is not attractive to most Western European consumers. In addition, reduction of the water content (drying) within the shelf- life period results in continuously degrading organoleptic properties. Besides preserving the original features of the product, a number of solutions, rarely applied in practice, have been developed in order to render the cheese material softer and more creamy. To this end, HU 9702192 describes the use of Ca²⁺ and Mg²⁺ salts as additives, and HU 219126 discloses the addition of milk powder. Both solutions result in an increase of solids content. The object of the present invention was to eliminate the above disadvantages of the prior art. Preferably, the Inventors' aim was to provide a product with a cream texture that would be highly attractive to a wide range of both Hungarian and European consumers while preserving the preferred characteristics of traditional fresh cheese preparations, for example, curd cheese desserts. In a preferred embodiment, the object of the present invention is to provide said product without the addition of significant amounts of additives. Development of the solution according to the present invention was based on the technology described in patent No. HU 217908 granted for Danone. It has been suφris- ingly found that appropriately treated fresh cheese may be treated to have a cream-like texture without significant overrun by applying high shearing effect, e.g. by simultaneous cutting and vigorous agitation with appropriate cooling and the resulting mass (pulp) can be shaped and extruded, while it preserves its shape in the absence of external forces. In addition, it was found that cutting by knives can be advantageously carried out in a cutter of a novel construction, comprising a receptacle equipped with jamming worm feeders for feeding and removal. 3. Brief Description of the Invention In one aspect of the invention, a method is provided for preparing acid- coagulated, fermented, fresh cheese with an extrudable and homogeneous texture by cutting, heating, pressing and agitating a fermented curd prepared from skimmed, homogenised, heat-treated milk, comprising: - pressing, which is continued until reaching appropriate solids content to obtain a cheese material, which, after agitation, can be converted into a material of plastic texture, - after pressing, the pressed curd is subjected to intensive high-shear agitation in a non-pressure-tight receptacle equipped with a cutting and blending device, until reaching a substantially homogeneous texture, while after appropriate cooling, the temperature is set to a value which, on the one hand, prevents overheating of the cheese material and the associated damage to proteins, and, on the other hand, prevents overcooling or sudden cooling, which would lead to the formation of dehydrated protein particles, and - if desired, fat content of the resulting homogeneous cheese material is adjusted by adding a high-fat ingredient, - if desired, further additives are added to said cheese material, then - optionally, said homogeneous cheese material is shaped, and - optionally, after shaping, said cheese material is enrobed. Preferably, according to the method of the present invention, the milk or milk ingredient, preferably milk, is inoculated with a pure mesophil starter culture and then fermented at a temperature ranging from 22°C to 36°C in closed fermenters to reach a pH of 4 to 5, preferably 4.4 to 4.9. In a particularly preferred embodiment, partly or fully homogenised milk with a fat content adjusted to 0.5% to 3.6%, suitably to 1.5% to 2%, is fermented. If desired, according to the method of the present invention, dehydration of the curd is substantially avoided at least during the cutting, heating and pressing of the curd. Dehydration of the curd during the above steps is preferably avoided by preventing any contact with the air. Highly preferably, a closed system is used. Preferably, according to the method of the invention, the curd is cut to pieces larger than pea-size, preferably to pieces, e.g. to cubes, with a size ranging from 2 to 10 cm, highly preferably from 3 to 6 cm. Preferably, according to the method of the invention, the cut curd is heated to 50°C to 80°C, more preferably to 65°C to 75°C, and highly preferably to 70°C to 72°C. Preferably, according to the method of the invention, pressing is continued to reach a solids content of 35% to 50%, more preferably to 35% to 48%, and highly prefera- bly to 38% to 43%. In a particularly preferred embodiment, pressing is carried out in two stages wherein pressing in the first stage is carried out under the whey and pressing in the second stage is carried out in a closed system where whey is allowed to drain. Preferably, pressing is carried out at the temperature of the cut and heated curd, preferably at 65°C to 75°C, highly preferably at 70° to 72°C. In a preferred embodiment, a fresh cheese of the curd cheese type is produced. Preferably, intensive high-shear agitation is carried out in a cutter equipped with a cutting unit, apt for a speed of at least 1,000 φm, or by providing at least an equivalent shearing force. In a particularly preferred embodiment, intensive high-shear agitation is carried out in a cutter equipped with a knife cutting unit and a scraper device, for 0.5 to 60 minutes, preferably for 1 to 30 minutes, more preferably for 2 to 20 minutes, and highly preferably for 5 to 12 minutes, using knives or knife pairs with a total length of 0.1 to 2 m, preferably with a total length of 0.2 to 1 m, at a speed of 1,000 to 6,000 φm, preferably 2,000 to 5,000 φm, and more pref- erably 2,500 to 4,000 φm, wherein preferably the minimal distance between the endpoints of the knives external to their axis of rotation and any other element of the cutter is less than 100 mm, preferably less than 60 mm; or agitation is carried out at a shearing effect equivalent to that determined by any combination of the above conditions. In a preferred embodiment, cool, inert gas is applied for cooling during high-shear agitation, more preferably an inert gas in gaseous state is applied, and highly preferably, nitrogen is applied, and any significant overrun of the cheese material is avoided during intensive agitation. In a highly preferred embodiment, the inert gas has a temperature of -40°C to - 160°C, the inert gas is introduced into the cheese material near the knives, and overrun is avoided by allowing the system to have a pressure not more that slightly, i.e. by 0.1 to 0.5 bar above atmospheric and nitrogen is optionally removed in order to prevent increase in pressure, and highly preferably atmospheric pressure is applied. Preferably, overrun during intensive agitation is not more than 10%, more preferably not more than 7%, and highly preferably not more than 5%. Preferably, during high-shear agitation, the curd is kept at a temperature between

0°C and 50°C, more preferably between 10°C and 34°C, most preferably between 15°C and 30°C. In a preferred embodiment, intensive agitation is followed by an adjustment of the fat content by adding of dietary fat. Preferably, the fat is butter, fatty cream, vegetable fat, such as margarine, or coconut fat. In a preferred embodiment, the fat content is adjusted to between 1% and 30%, preferably to between 2% and 25%, more preferably to between 5% and 22%o or about 9% and 22% of the total mass of the cheese material. In another embodiment, intensive agitation is followed by the addition of other additives, preferably dextrose, sucrose, K-sorbate and/or flavourings, such as vanilla, co- conut, cocoa, chocolate, fruit, coffee or other types of flavourings of the same taste, and optionally other additives. In another embodiment, the cheese material of homogenous texture is extruded. In another embodiment, at least two kinds of cheese material with different composition or flavouring are coextruded, or the cheese material(s) is (are) extruded together with other materials, such as fruit gel. According to a further embodiment, instead of one of the cheese materials, for example the colored, flavored cheese material, a sweetened milky cream is coextruded with the above cheese material. Said milky cream may be colored and/or flavored. Preferably, after extrusion, the cheese material is cut and then enrobed with a coating mass. In a highly preferred embodiment, the apparatus of the present invention is used as cutter. In another aspect of the invention, acid-coagulated, fermented fresh cheese is provided, which is plastic and of homogeneous texture at atmospheric pressure and at least at one temperature selected from 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C and 40°C, and contains gaseous material at a ratio of at most 5% per volume, preferably at a ratio of at most 1% per volume. Preferably, the fresh cheese according to the invention is extrudable and has a creamy texture. Preferably, the fresh cheese according to the invention is plastic and extrudable in any of the temperature ranges selected from 10°C to 14°C, 14°C to 19°C, 19°C to 23°C, 23 °C to 27°C, 27°C to 31°C, and, preferably, is plastic and extrudable at least between 19°C and 23°C. In another embodiment, the invention provides fresh cheese obtainable by any of the methods of the invention. Preferably, the fresh cheese according to the invention is fresh cheese of the curd cheese type. In a preferred embodiment, the pure fresh cheese or the fresh cheese according to the invention shows lower penetration in a penetrometer test than a control product prepared using the same method but without high-shear agitation. In a preferred embodiment, the pure fresh cheese or the fresh cheese according to the invention has lower water activity than a control product prepared using the same method but without high-shear agitation. In a preferred embodiment, the pure fresh cheese of the curd cheese type according to the invention has a water activity between 0.87 and 0.92, preferably between 0.88 and 0.91, and highly preferably about 0.89. In a preferred embodiment, the fresh cheese according to the invention, upon fat content adjustment, has a water activity between 0.90 and 0.95, preferably between 0.91 and 0.94. In a preferred embodiment, the pure fresh cheese or the fresh cheese according to the invention has a smaller particle size than a control product prepared using the same method but without high-shear aσitatinn. In another aspect of the invention, the present invention provides an acid- coagulated, fermented fresh cheese preparation, which is produced by mixing: - pure fresh cheese, in a ratio of 40% to 98% - dietary fat, in a ratio of 2% to 20% - and, if desired, other additives, optionally dextrose, in a ratio of 0% to 20% sugar, in a ratio of 0% to 18% one or more other additives, such as K-sorbate, texture improvers, spices, etc., in a ratio of 0% to 6% and which is plastic and of homogeneous texture at atmospheric pressure and at least at one temperature selected from 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C and 40°C. Preferably, the fresh cheese or fresh cheese preparation of the invention is fla- voured, and highly preferably, contains vanilla, coconut, cocoa, chocolate, fruit, coffee or other types of flavourings of the same taste, and optionally other additives. Furthermore, the present invention provides a fresh cheese preparation prepared by further processing of the fresh cheese of the invention, wherein the ratio of pure fresh cheese in the fresh cheese preparation is between 20%) and 50%, preferably between 30% and 50%. In another aspect, the present invention provides a dairy dessert prepared from the fresh cheese or fresh cheese preparation of the invention, which is preferably a dairy dessert prepared by shaping or extruding the fresh cheese or fresh cheese preparation. In one embodiment of the invention, the dairy dessert is prepared by the coextru- sion of at least two different types of fresh cheese preparation, for example, of at least two fresh cheese materials or fresh cheese preparations with different flavouring or a fresh cheese and a SΛveetened milky cream. In case a fresh cheese preparation and a sweetened milky cream are used, the preferred composition of said milky cream is as follows: Vegetable or milk butter: from 20 to 37 %, Sweetener: from 50 to 28 %, Fatty or skim milk powder: from 5 to 15 %, Whey powder: from 8 to 2.36 %, CocOFJ nowder rxr vnσπrt nnwHpf frnm ^ tr> 1 A o , Flavoring concentrate: from 12 to 2 %, Lecithin: from 0.1 to 1.5 %, Aroma: from 0.9 to 0.04 %. The flavoring concentrate may be among others chocolate, nut, vanilla, chestnut, caramel, fruit concentrate, etc. The weight ratio of the milky cream to fresh cheese preparation may vary in a wide range such as 50:50, 40:60, 30:70, 20:80, etc. In one embodiment of the invention, the dairy dessert is enrobed by coating mass, wherein the coating mass is preferably chocolate substitute cream, e.g. cocoa mass or nou- gat cream; or chocolate, for example white chocolate, milk chocolate or black chocolate. According to another aspect, the present invention provides an apparatus of batch operation, particularly designed to cut and blend food materials of soft consistency, comprising a receptacle with a closable lid, and an engine-driven knife cutting unit arranged in the receptacle, and is further equipped with at least one jamming worm feeder embedded in a housing, attached to the receptacle from outside, arranged to provide direct communication with the inner space of the receptacle through an opening in the wall of the receptacle to allow feeding into and removal from the receptacle of the required material(s). Preferably, the receptacle is a drum with a cylindrical wall, and has a front lid and a rear lid in opposite arrangement, and preferably, the axis of the drum is substantially horizontal, and at least one jamming worm feeder is attached to the lower part of the drum, and the opening in the wall of the drum is arranged at the lower part of the drum wall. Preferably, the apparatus is further equipped with a scraper unit capable of scrap- ing the wall of the receptacle. In a preferred embodiment, the scraper unit, the knife cutting unit and at least one jamming worm feeder are equipped with individual driving units. In a particularly preferred embodiment, the drum is a stainless steel drum, the knife cutting unit comprises a shaft and knife pairs, the scraper unit comprises a shaft and a scraper, the shaft of the scraper unit runs through the front lid of the stainless steel drum, and the shaft of the knife cutting unit runs through the rear lid, the front lid, through which the shaft of the scraper unit runs, can be opened and the jamming worm feeders are arranged in pairs, are mounted in individual housings, and optionally, the apparatus comprises only one pair of jamming worm feeders, the driving unit of the jamming worm feeders drives one or more jamming worm feeders, the driving units of the jamming worm feeders, scraper unit and/or knife cutting unit are electric motors, preferably electric- motors with regulable speed, preferably electric motors controlled by frequency changer. In a particularly preferred embodiment, the shaft of the knife cutting unit is arranged eccentrically, under the axis of the drum. Highly preferably, the diameter of the stainless steel drum is 0.2 to 2 m, preferably, 0.5 to 1 m, and the length of the knife pairs is 0.1 to 1.5 m per pair, preferably 0.25 to 0.6 m per pair, and the minimal distance between the arc of circle defined by the rotational motion of the endpoints of the knife pairs and the at least one jamming worm feeder is less than 200 mm, preferably less than 100 mm, and highly preferably is 20 to 60 mm. In another particularly preferred embodiment, the number of the knife pairs is one to five, preferably two to four, and the distance between individual knife pairs is 10 to 200 mm, preferably 30 to 100 mm, only one pair of jamming worm feeders is attached to the apparatus, and the driving unit of the knife cutting unit is an electric motor with a nominal ca- pacity of 25 to 100 kW, preferably 30 to 8O kW or 40 to 60 kW. 4. Definitions "Pure fresh cheese " means cheese prepared by fermenting acid-coagulated milk or milk ingredient(s), wherein the cheese is suitable for human consumption in a fresh state or after only a short period of ripening, and does not contain additives other than the proc- essed curd prepared from fermented milk or milk ingredient and materials required for processing the curd (i.e., salts, buffers, curd washing residue, etc.). Preferably, the pure fresh cheese does not contain rennin (rennet) or contains it in an insignificant (negligible) amount. "Fresh cheese" means acid-coagulated cheese prepared by fermenting milk or milk ingredient(s), wherein the cheese is suitable for human consumption in a fresh state or after only a short period of ripening and the total ratio of milk products of other origin and other additives is not more than 60%, preferably not more than 55% or 50%, and the features of pure fresh cheese are dominant in the product. Fresh cheeses include, for example, cheeses made of cream, whey cheeses and various curd cheeses. Well-known traditional fresh cheeses include, for example, the cottage cheese produced in English-speaking countries, the French cream cheese or "fromage frais", the German curd cheeses, e.g. "Bauernlcase" and "Quark", and the Italian "Ricotta" cheese, and also the Hungarian clumpy curd cheese (of cauliflower-like texture), "tύrό". Taking into consideration the modifications according to the present invention, the methods of preparing any of the above can be used for the puφose of the present invention. Fresh cheeses "of the curd cheese type" or pure fresh cheeses ( "curd cheese types") are produced from milks with various fat content by either microbiological acid- coagulation only or by microbiological acid-coagulation with an additional coagulation by rennet. "Fresh cheese preparation " means a product prepared by processing or further modifying the fresh cheese in a manner that the presence of the fresh cheese component remains readily tasteable. Preferably, the fresh cheese preparation contains at least 5% and at most 80%, preferably at least 10% and at most 70% of additives of milk or other origin in addition to the pure fresh cheese. Therefore, the scopes of products defined as fresh cheese and fresh cheese preparation overlap. "Sweetened milky cream" means a cold mixed cream having high dry material content, prepared by using a considerable amount of the basic materials of the dairy indus- try. "Dehydration of the curd" means a process of water removal from the solvate shell of the proteins in the curd by contact with the air. The lower pH induced by acidification is closer to the isoelectric point of the proteins, which also promotes the above process by reducing the stability of the solvate shell. Codd air also enhances this effect. "Curd processing" involves at least the cutting and pressing of the curd, optionally the heating or afterheating thereof, and, if desired, the agitation thereof. "Pressing" means a process or a series of processes of reducing the water content of the curd, preferably until the desired level. In the description, "cutter " means an apparatus for cutting and blending (includ- ing adding additives to) dairy masses, comprising a non-pressure-tight container. "Non-pressure-tight container" means a container, in which pressure equalises with the atmospheric pressure within a technically finite period of time, preferably within less than a day or an hour, more preferably witJhin minutes, e.g. within 15, 10, 5 or 2 minutes, even if the mntftiner IQ HΠQPΓI "Significant overrun of the cheese material" means an increase in volume that is detectable by instruments or by inspection under the given conditions and that is due to gaseous substances enclosed in the cheese material. Preferably, significant overrun is not less than 2%, 5% or 10%). Significant overrun may be detectable by the consumer as ex- pansion. "High-shear agitation" ox "stirring under high shearing effect" of the curd means an agitation or stirring or other mechanical process, which substantially modifies the microstructure and rheological properties of the curd. "High-shear agitation" significantly increases the dispersion degree of the curd suspension, preferably by at least 1.5, 2 or 5 times, or even at least 10, 20, 50 or 100 times. A skilled person will understand that the dispersion degree can be calculated by different methods, such as on the basis of the particle size, volume, etc. and can be expressed as an average. It can also be given as a parameter of a distribution curve. For characterizing a specific pr duct any method may be used provided a suitable control is applied. Preferably, the texture becomes homogeneous. High shearing force is achieved by rotating knives or knife pairs with a total length of e.g. 0.05 to 2 m, preferably 0.1 to 1 m, more preferably 0.25 to 0.5 m at a speed of 1,000 to 6,000 φm, preferably 2,000 to 5,000 φm, more preferably 2,500 to 4,000 φm, the minimal distance between the endpoints of the knives external to their axis of rotation and any other element of the cutter is less than 200 mm, preferably less than 100 mm, more pref- erably less than 60 mm; or by ensuring a shearing effect equivalent to that determined by any combination of the above conditions. "Homogenous texture" means a texture of the fresh cheese or fresh cheese preparation that appears homogeneous to the relevant human perceptions (sight, touch or taste) without using any instruments. Preferably, "homogeneous texture" means a suspension of the fresh cheese or fresh cheese preparation that has an average particle size of not more than 100 μm or 60 μm, preferably not more than 40 μm or 30 μrn, highly preferably not more than 28 μm. "Creamy texture" refers to organoleptic properties of the fresh cheese that the consumer feels cream-like upon tasting and mechanically impacting it with the tongue. "Extrudable cheese material" means a cheese material than can be shaped by customary food extruders used in the food industry, preferably in the dairy industry, e.g. in cheesemaking, under normal conditions, such as without the need for elevated pressure, i.e. a pressure higher than 2 bar, preferably 1.4 bar, more preferably 1.2 bar, and without the need for a temperature outside the range of 0°C to 50°C, on either side of the extruder. "Plastic " cheese material means a cheese material that, upon application of an external force higher than a given threshold, can be changed into a new shape following the direction of the force, without breaking or cracking, and this new shape is preserved even after elimination of the external force; and this holds for a suitably wide range of external force intensity by which the cheese material can be shaped. Naturally, the plastic material may behave as an elastic object for forces under the lower limit and as a. rigid object for forces above the upper limit. In the lack of external forces, the plastic cheese mate- rial has a stable shape, unlike liquids. The method of the present invention and the apparatus suitable for the uφose of this method are described in more detail in reference to the embodiment example shown in the figure attached to the present description. Figure 1 is a draft vertical cross-section of a cutting and blending apparatus (cut- ter) according to the present invention, without support. Said apparatus is suita ble for intensive stinϊng (agitation) of cheese materials, in particular, suitable for thereby achieving a homogeneous texture. 5. Detailed Description of the Invention The cutter shown in Figure 1, which is suitable for preparing fresh cheese ac- cording to the present invention, is of batch operation and is particularly desigςned to cut and blend food materials of soft consistency. The cutter comprises a receptacle, optionally a stainless steel drum 1 with a closable lid, which preferably has a substantially horizontal axis. The drum 1 comprises a wall of a cylindrical shape, a front lid 2 and a rear lid 2'. The front lid 2 of the drum 1 opens together with the scraper unit, which consists of? a shaft 7' and a scraper 5 and functions as both a scraper of the inner surface of the cylindrical wall and as a stirrer. The shaft 7 of the electric motor driving the knife cutting unit 4 runs through the stable rear lid 2', and knife pairs 3 (e.g. two, three, four or five pairs of knives) are attached to the shaft by mounting bases arranged at suitable intervals. From the outside, one or more, preferably two jamming wonn feeders (i.e. one pair of jamming worm feeders) 8 embedded in housings 9 of suitably semi cylindrical shape are attached to the drum 1, which are designed to feed and remove the required materials through an opening in the wall of the drum. The housing 9 and the jamming worm feeders 8 are mounted to the bottom of the drum 1, and the opening in the wall of the drum unit is arranged eccentrically, under the axis of the drum 1; therefore, the distance between the arc defined by the rotation of the endpoints of the knife pairs and the inner wall of the drum 1 is the shortest at the bottom of the drum. Parameters of the exemplary cutter are as follows: - diameter of the stainless steel drum 1: 660 mm, - number of knife pairs 3: three, with a length of 360 mm/pair, - distance between knife pairs 3: 60 mm, - distance between jamming worm feeders 8 and tips of the knives: 40 rnnx, - diameter of jamming worm feeders 8: 200 mm, - nominal capacity of the electric driving engine of the knife cutting unit 4: 56 kW, - maximum rotational speed of the knife cutting unit: 3200 φm. The cutter is operated in a batch fashion. The material to be cut by the jamming worm feeders 8, i.e. the cut and pressed curd in this example, is transferred to the drum 1 through the opening arranged at the bottom of the drum, suitably during the operation of the knife pairs 3. Simultaneous operation of the jamming worm feeders 8 and knife pairs 3 enhances the shearing effect. During stirring and cutting, further additives may be fed into the drum 1 by the jamming worm feeders 8 without interrupting the process. After the process is finished, the so prepared homogeneous, blended curd can be easily removed from the drum 1 using the jamming worm feeders 8, as the curd is transferred to the jamming worm feeders 8 by gravitation. The horizontal arrangement of the drum 1 and the attachment of the jamming worm feeders 8 to the bottom of the drum 1 result in low volume need and allows for an easy insertion of the apparatus into the process line. The starting material of the product is milk, which can be any kind of milk suitable for human consumption, such as cows' milk, ewes' milk, goats' milk, horses' milk, etc. Upon appropriate pre-treatment (filtration, cooling, storage), the milk is pasteti-rised at a temperature of 72°C to 120°C, preferably at 95°C, and skimmed. Alternatively, any material of milk origin suitable for cheese making can be used, provided its fat content is or has been adjusted by, for example, cream or vegetable fat to a suitable level, preferably to 0.2% to 10%, more preferably to 0.5% to 4%. Preferably, the starting material is milk with a fat content of 0.5 to 3.6% g/g, highly preferably with a fat content of 1.8%> g/g, or skimmed milk with its fat content ad-

IllQt H l _A/PO"Ptnh1 fat nr 'f r_'a I_'lT- nr_r_*r_r_tx+ -f + AT-v-'-f +!»-_ nised at a pressure of 40 to 240 bar, preferably at a pressure of 200 bar. Thereafter, it is preferred to apply a second heat-treatment. Alternatively, fermentation may be carried out using thermophil strains, but preferably a pure mesophil starting culture, especially preferably a pure mesophil culture not producing carbon dioxide is used. For example, Streptococcus lactis and Lαctococcus lαc- tis bacteria and preferred strains thereof may be used. The strains used in the invention are advisably phage-resistent. The temperature to be applied is determined by the optimal proliferation temperature of the pure mesophil starting culture, and is preferably between 22°C and 36°C (highly preferably 30°C). Preferably, ripening is carried out in closed fermenters, and the pH reduction characteristic of the products is achieved, for example, within 6 to 10 hours, which pH is preferably between 4 and 5, more preferably between 4.4 and 4.9, and highly preferably between 4.45 and 4.55. The size of the curd pieces (e.g. curd cubes) obtained by cutting the curd is of importance for the puφose of the invention, although the inventors' experience suggests that it is highly preferable to obtain clumps with edges of uniformly 3 to 5 cm, which are well- suited to "enclose" free water. Nevertheless, the size of the curd cube is a "coarse" parameter since it is difficult to achieve a completely uniform size. Very small clump size is not preferred because it is liable to quickly release water and makes it difficult to obtain a homogeneous structure. It should be noted here that quick water release may also be due to an abnormal composition of the starting milk, e.g. it has a low Ca²⁺ content. The cut curd is subjected to intensive heating, preferably to 50°C to 80°C, more preferably to 60°C to 75°C, and highly preferably to 65°C to 74°C or to 70°C to 72°C, preferably without moving. During all the heating procedure the cut curd is being maintained under the hot whey in order to completely avoid dehydratation of the curd clots. After achieving the desired temperature, the curd- whey mixture is suitably transferred to a pressing-shaping apparatus. Current knowledge suggests that it is important to avoid dehydration of the curd and the associated loss of water by the proteins during the treatment of the curd. When the curd is in contact with the air, the risk of such dehydration is very high, because acidifica- tion results in a pH close to the isoelectric point of the proteins at which the stability of the solvate shell of the protein molecules is reduced. Avoiding dehydration and the associated development of a loose and particulate structure ensures the potential for a subsequent process applied to obtain a creamy texture and a higher level of microbiological safety for a Pressing is suitably carried out in two stages. During the first stage, the curd is pressed under the whey. In the second stage (after the curd is appropriately agglutinated) pressing occurs in the absence of air, in a closed system with free draining of the whey. As a matter of course, a completely closed system may be used for both stages. Preferably, the solids content of the curd is 35%) to 40%, preferably 37%) to 45%, and highly preferably 40% to 42%, e.g. about 41%. The inventors' experience suggests that transferring of the curd should also occur in a closed system to avoid dehydration. As apparent from the present specification, the key elements of the process for curd cheese production developed by the inventors are in disagreement with the traditional processes applied in Central Europe, which are based on open curd processing, curd dehydration and a cauliflower-like consistency. However, traditional chocolate-coated (enrobed) curd cheese desserts ("Rudi" products) have been produced so far exclusively by processes based on curd dehydration. Storage of the curd may be carried out in a number of ways; however, care should be taken to avoid dehydration during storage, as well. One alternative is to keep the curd warm, even at temperatures as high as 40°C to 50°C, for a short period, preferably for not more than a day or 10 hours, more preferably for 4 to 6 hours. Another alternative is to cold-store the curd in a closed area. In this case, the curd may be stored for longer periods. For the puφose of creating creamy texture, a closed but non-pressure-tight apparatus has been developed, which is exemplified in Figure 1. The one or more jamming worm feeders attached to the receptacle allow the pressed curd to be fed into the receptacle and, upon stirring and cutting, to be removed therefrom. In this manner, the additives to be added to the curd can be fed into the apparatus during the stirring and cutting process, without opening the system. If the jamming worm feeders are attached to the bottom of the receptacle (preferably a stainless steel drum), removal may occur by gravitation. High shearing is generated by the cutting unit, which is preferably a knife cutting unit. The cutting unit may be of any shape that is capable of generating high shearing force. The knives or knife pairs are suitably attached to the shaft of the driving motor that runs through the lid of the receptacle. The shearing force may be further enhanced by an eccentric shaft arrangement, which results in the knives travelling close to the inner wall of the receptacle at certain locations where the shearing force will be higher. Preferably, the jamming worm feeders feed the curd into the receptacle near this point, which may further inr.rp.fiςp. flip, ςh a inσ pffppt Preferably, the front lid of the apparatus can be opened together with a scraper unit, which ensures a scraped inner surface and allows for the cleaning of the receptacle. The apparatus is suitably equipped with a device suitable for feeding liquid or gaseous inert gas into the system. Naturally, any other cutting and stirring apparatus, e.g. cutter or other apparatus capable of generating high shearing force may be used for obtaining a curd of homogeneous structure. Several such apparatuses will be known to those skilled in the art. In addition, setting of the parameters required for the preparation of creamy fresh cheese with the desired homogeneity and texture can be made without undue experimentation by one skilled in the art in the light of the present disclosure. Therefore, the process can be carried out in, for example, a two-parted plate cutter, as exemplified below. The dairy industry uses a number of different cutters, e.g. cutters with capacities ranging from 25 kg to 300 kg. Any of these cutters may be used in the method of the present invention, provided the shearing force is appropriate, feeding and removal of the cheese material and, if desired, of the additives is possible and cooling is ensured. In order to obtain the desired creamy texture, the pressed curd is suitably transferred to the cutting and stirring apparatus via a closed system. In the first step, the knives are operated at a high speed and, if an apparatus of the present invention is used, the cheese material is transferred to the knives by the jamming worm feeders to create a particle-free, smooth milk protein concentrate (curd cheese). Creation of the creamy texture may be carried out at a temperature between 0°C and 50°C, wherein the optimal temperature is between 18°C and 30°C according to the inventors' experience. Local overheating may cause damage to the consistency of the product as it may result in local denaturation or phase inversion. When inert gas is added, intensive and sudden overcooling may result in significant water removal, which may promote the formation of dehydrated protein granules. Alternatively, other cooling methods (e.g. heat exchangers, liquid inert gas) may be used provided that the above conditions are ensured. Addition of liquid inert gas, such as liquid nitrogen is highly cumbersome as there is a high risk of curd cheese particles freezing onto the injector head. Based on the present disclosure, those skilled in the art will be able to identify the appropriate parameters for the given operational conditions to avoid such risks. The increased surface area of the resulting protein structure significantly reduces the free water content of the system (thereby increasing the amount of colloidal water), which prevents drying during the shelf-life period as compared to traditional products. In certain cases, the cheese material is dried by the inert gas, which is advanta- geous within certain limits. The time required and sufficient for the application of the high shearing stress or, in general, the high shearing effect is determined by experimentation. In general, the cheese material may be subjected to organoleptic inspection, i.e. by tact or tasting, or either the viscosity or the particle size distribution (e.g. by microscopic examination), or the dis- persivity quotient of the resulting suspension may be determined by any well-known methods. The water retaining capacity of the cheese material is also a good indicator of the degree of dispersion. Plasticity of the cheese material may be characterised by penetrometer analysis. After the process of creating homogeneous structure, direct injection of an inert gas, preferably nitrogen gas of a temperature of -40°C to -160°C, into the curd cheese cream ensures intensive cooling and microbiological safety when the cutting and stirring units of the apparatus are operated at a high speed. If desired or preferred, the fat content of the cheese material is adjusted. This may be achieved by the addition of any suitable high-fat materials, for example, by the addition of butter, vegetable fat, e.g. margarine, coconut fat, or possibly high-fat cream, while the cheese material is intensively cooled. In addition, the rotational speed used for the high- shear agitation is reduced, preferably to at most 80% and at least 5% (if the apparatus exemplified in the present description is used, the rotational speed is reduced from 3,000- 4,000 rpm to 200-2,000 φm or to 500-1,500 φm); however, the exact value may be read- ily determined by experimentation. After creating the creamy texture, the desired additives (cocoa powder, chocolate, sugar, dextrose, butter, fruit, seeds, muesli, biologically active minerals, vitamins, flavourings, colourants, consistency improvers) are added according to the formulation, preferably at a lower rotational speed. During this stage, cooling can be less intensive. By operating the apparatus at a stirring speed, mixtures may be prepared according to a given protocol. This process may be used for the preparation of filling masses of a wide variety colours and taste combinations. Plasticity, which means that the product can be shaped and will have a stable shape, and, optionally, can be extruded, is an important feature of the product. This feature depends primarily on the surface increasing effect (increasing also water binding capacity ) of the process creating the creamy texture. Plasticity is influenced by the thixotropic prop- erty of butter, and other additives also have an effect. For example, high levels of sweeteners may have a negative effect. Evidently, plasticity also depends on temperature. Upon blending, the masses ready for extrusion may be transferced to a shaping apparatus, preferably by automated transfer, for example by operating the jamming worm feeders in a suitable mode of operation. Extrusion may be carried out in a fashion to generate rods either with a rectangle-shaped, e.g. square-shaped, or oval or circular cross- section. When more than one types of masses are to be extruded simultaneously, coextru- sion is applied. -Depending on the arrangement and shape of the extruder heads, the coex- traded cheese materials may be interbedded, e.g. in a concentric or other fashion, or may be arranged in any divided layout, e.g. a cheese material of a given type or taste arranged at under the other (see e.g. Danone Duett Rudi). The filling masses of different colour and taste, which may be filled and shaped in a wide variety of ratios are transferred to a conveyor belt or conveyor belts running underneath at the same speed as the shaping (extru- sion) belt(s). Alternatively, shaping methods other than extrusion, such as casting into moulds can be used. Upon shaping, the product may be cut to size, if desired. If the still not enrobed slices of plastic property, which have a light, creamy texture, are highly sensitive to mechanical forces or highly liable to damage, cooling is suita- bly applied before the first immersion. One alternative is to apply a cooling tunnel cooled by an inert gas. In another alternative, a belt running through a base freezing tunnel cooled by liquid nitrogen is used (belt temperature: -40°C to -160°C). Due to the direct contact between the belt and the slices, the base or "bottom" of the slices are frozen up to height of 2 to 3 mm resulting in shape stability, resistance to damage and improvement of the quality of coating. Upon shaping, the product may be enrobed. This may be done by any known enrobing (coating) methods. These include enrobing by wax or by liquid cheese. Another alternative is the application of the traditional "chocolate curtain" immersion. In addition to chocolate, any other suitable coating mass may be used. Furthermore, the product may be enrobed by sugar icing. In addition, a second coating may be applied. In an aesthetical embodiment, this second coating does not completely cover the first coating. In such cases, elevated level of base-coating may be applied, which results in a coating that covers 50%>, 20%, 30%o, 40%), 70%), etc., of the slices (e.g. Danone Duett Rudi). The coatings may be further decorated.

EXAMPLES Example 1 Preparation of pure curd cheese material in the form of a pressed curd Pre-treatment of the milk The starting material, i.e. milk is pre-treated by customary pre-treatment methods (filtration, cooling, storage), pasteurised at a temperature of 72°C to 120°C (in practice, at 95 °C), and skimmed. During further processing solely skimmed milk is used. Fat content of the starting milk is adjusted by the addition of cream or vegetable fat, such as coconut fat, to approximately 1.8% w/w. Thereafter, the milk is partly or fully homogenised under a pressure of 200 bar. Upon a second heat-treatment and subsequent cooling, the resulting milk material is pumped into fermenters. Fermentation, ripening The temperature of the milk is gradually increased to 22°C to 36°C (preferably to 30°C) and then the milk is inoculated with the pure mesophil culture "DSG 2000/70". In another variant, a pure mesophil culture not producing carbon dioxide is used. In the closed fermenters and at the desired temperature, the pH reduction characteristic of the product (a target pH of 4.4 to 4.6; preferably a target pH of 4.45) is obtained within 10 hours. Curd processing, pressing Upon achieving the firmness of the curd characteristic to that of the product, the curd is cut to cubes with a size of 3 to 5 cm and then intensively heated without moving

(i.e. cutting or stirring) in order to increase the curd syneresis. The process is carried out in a closed system with due care to avoid dehydration on the surface of the curd. Next, the temperature of the curd- whey mixture is suitably adjusted to about 72°C. By using the pure mesophil culture not producing carbon dioxide the curd plots can easily be maintained under the whey level during the whole heating procedure. The curd-whey mixture is then transferred in a closed transfer system to a closed pressing and shaping apparatus. In the first stage, the curd is pressed under the whey. In the second stage (after the curd is appropriately agglutinated) pressing occurs in the absence of air with free draining of the whey. Upon achieving the desired solids content (approximately 41%), the shaped curd blocks are transferred to double-walled, coo- lable and heatable storage tanks, which have a capacity of several tons. Again, closed systems should be used to avoid dehydration of the curd. Example 2 Traditional curd preparation method (comparative example) This process is substantially the same as the one described in Example 1, but heating was carried out at a temperature of 78°C to 80°C and whey was pressed until a solids content of about 49% was achieved. -Another important difference was that curd was allowed to contact the air during the second stage of pressing, thereby allowing curd dehydration to occur and a "clumpy" curd structure to develop. Example 3 Preparation of cheese filling by high-shear agitation method Creamy texture may be achieved in a traditional cutter of appropriate performance or in the apparatus with horizontal drum design developed for this puφose by the inventors (Figure 1). Achieving creamy texture in a horizontal cylindrical cutter In a closed system, the curd cheese is pumped into the apparatus designed to create a creamy texture. In the first step, the material is intensively transferred by the jamming worm feeders 8 to the knife pairs 3. Next, by operating the knife pairs 3 at a speed of 3,200 φm, a particle-free, homogeneous, smooth milk protein concentrate (curd cheese) is obtained. Meanwhile, nitrogen gas with a temperature of -40°C to -160°C is directly injected by "trickling" into the curd cheese cream in order to suitably keep it at a temperature of 18°C to 30°C, preferably at a temperature of 20°C to 22°C. Under the conditions described in this example, this step takes 5 to 12 minutes, preferably about 7 minutes. Nitrogen gas is generated from liquid nitrogen kept at a pressure of 5 bar by forcing it through a pipe with a length of 1 to 2 m before injection, wherein the liquid is converted to gas when the vacuum insulation is over and its temperature raises to -40°C to - 16O°C. In the specific example, the temperature Λvas closer to the upper limit, which was still suitable for intensive cooling and water removal. Characterisation of the creamy texture In order to characterize the texture obtained by the novel high-shear agitation method, we compared the penetration and the Stevens strength of the pure curd cheese material of Example 1 to those of the creamy cheese obtained from the cutter in this Example. The penetration (P) was measured by a δhler K 95500 penetrometer with a normal fat cone, expressed as the penetration in 0.1 mm in 5 sec. The strength (si) was measured by a Stevens's LFRA Texture Analyzer, using a speed of 0.2 mm s, until a depth of 2 mm, expressed in gram force (g). For the above rheological measurements the samples were filled into a 250 ml plastic pot, incubated 48 hours at a temperature of 5 °C +/- 0.5 °C. The measures were made at a sample temperature of 5 to 10 °C. The following results were obtained:

From these results it can be seen that both parameters measured show a higher strength of the curd cheese after the treatment in the cutter reflecting that smaller particle size results in a more solid texture of the cheese material. In another study we compared the creamy texture of our white cheese filling to that of a control product, which was prepared in a similar way except for allowing the curd-whey mixture to dehydrate during the heating process and not applying a high shear agitation. We measured the finnness and the adhesiveness with a Stable Micro System TA- XT2 Texture Analyzer. Both parameters were expected to be higher for the product ac- cording to the invention due to a smaller particle size. We used a stainless steel cylinder probe of 2 mm diameter and a speed of 1 mrn/sec for 10 sec (i.e. to a 10 mm depth) in compression, then for 10 sec in tension. The samples were incubated for 24 hours at 10+/- 0.5 °C. Experiments were carried out longi- tπrl-_ ncilK frx fli ocunnloi? Vxvnx x-x +T,-> -F/.11, The firmness which is the maximal force before compression is stopped (the maximum of the curve, expressed in g_max) and the adhesiveness, which is the greatest absolute value of the force upon starting the tension (the minimum of the curve, expressed in g_mi_n). The following results were obtained:

Ns discussed above, firmness (strength) is adversely correlated to the particle size of the product. As it can be seen, the adhesiveness is also higher according to the invention, which can be explained by a larger overall surface of the particles due to the smaller particle size. Larger particles like grains do not adhere to the surface of the probe to the same extent. In this context the nearly 20% difference in adhesiveness is significant. Thus, both parameters in the above table reflect the creamy texture of the product. The particle size was studied by digital photography of sample dispersions with a light microscope using the Colim image-processing program. The dispersions were prepared as follows: 1.0 g of the sample was introduced in a test tube, 10 ml of distilled water was added and the tube was shaked at 25 Hz for 60 sec, then it was sedimented for 60 sec, and finally, from the 70 mm high water column, at a height of 25 mm, 0.8 ml of dispersion was sucked with a syringe and filled in a Bϋrcker chamber. Before the photography the dispersion in the Burc er chamber was sedimented for lO min. Figure 2: shows the picture of the curd cheese of Example 1 before the high shear agitation, together with a 0.1 mm scale. Figure 3 : shows the picture of the curd cheese from cutter (after the high shear agitation together with a 0.1 mm scale. Comparing the pictures of the samples of fresh cheese materials before and after high shear agitation, it can be seen that particle size has been significantly reduced by high shear agitation. Upon obtaining the creamy texture, butter is added in order to adjust the fat content of the product to 10% to 17%). This is carried out at a speed of 500 to 1,500 φm and under intensive cooling by nitrogen (here, the cheese material is cooled to 18°C to 22°C. Next, the rotational speed of the knife cutting unit 7 is reduced to 500 φm and other additives, namely dextrose, sucrose, Ultratex 4, Alta 2O01 and K-sorbate (see Table 1) are added under "trickling" nitrogen cooling. A salty variety of the product may be prepared by replacing the sweet additives by salty ones, i.e. by sodium chloride, bay salt, iodinated salt, Na-gluatamate, etc., in amounts required to achieve the desired taste. Parameters of the novel cutter: Drum diameter: 660 mm Drum depth: 420 mm Knife centricity: shifted from the centre by 68 mm Diameter of knife pairs: 360 mm Distance between knives: 60 mm Distance between jamming worm feeders and tips of knife: 40 mm Diameter of jamming worm feeders: 200 mm The current drain of the 56 kW electric motor driving the knife cutting unit 7 at 3,200 φm is approx. 100 A, while it was 50 A during the blending stage. The level of water removal calculated for the above three stages (creation of the creamy texture, fat content adjustment, addition of additives) is 0.5 1 of water removed per 100 kg product. Finally, the creamy product is removed and transferred to the extruder unit. Achieving creamy texture in a traditional cutter In a traditional cutter, creamy texture was achieved using substantially the same method as above, except for the fact that feeding and removal was not earned out by jamming worm feeders, and the efficiency of the cutting and stirring was lower when applying the same rotational speed. Cutter parameters: Total diameter of the two-parted plate: 1245 mm Diameter of one plate part: 550 mm Dia eter of centrical crankshaft: 145 mm Knife diameter: 540 mm Distance between knives: 15 mm Plate rotation stages (baffling to the knives): Stage I: 5 φm Stage II: 10 φm Stage III: 22 φm During creation of the creamy texture, the speed of the knives was set to 3,200 φm as above. Preparation of a creamy cheese material with chocolate, vanilla or coconut flavouring The flavoured cheese material is prepared as above, except for the flavourings, which are added to the cheese material together with the other additives using low-speed stirring. For chocolate flavouring, cocoa powder and chocolate mass is added (see Table

1). For vanilla flavouring, vanilla sugar is added. For coconut flavouring, coconut grating is added. The flavoured material may also preferably be a milky cream having the composition specified above. If the product is intended for further processing, it may be extruded and the ex- truded product may be enrobed (see Examples 4 and 5). Example 4 Extrusion Upon blending, the masses ready for extrusion are transferred to a shaping apparatus by automated transfer. If a cutter with jamming worm feeders according to the inven- tion is used, this step is carried out by operating the jamming worm feeders. Upon shaping, the slices are cut to size. The not yet enrobed, plastic slices, which have a light, creamy texture, are highly sensitive to mechanical forces or highly liable to damage because although their shape is stable, they are plastic. Therefore, intensive cooling is applied before the first immersion, which is carried out in a foot freezing tunnel cooled by liquid nitrogen. The belt running through the tunnel (which is cooled to -40°C to -160°C) is in direct contact with the slices and, therefore, freezes the base of the slices up to height of 2 to 3 mm, which results in shape stability, resistance to damage and improvement of the quality of coating. Coextrusion of two different kinds of masses A preferred embodiment of the dairy desserts of the invention is Duett Rudi, which, when finished, comprises two sectors of different types in a cylindrical bar, preferably of different colour, attached to each other at a varying ratio; therefore, it requires a common extruder/shaper unit and two cutters of parallel operation, arranged vertically. In case a fresh cheese preparation and a milky cream are coextruded, the fresh cheese preparation should be below the milky cream so as to serve as a support for the latter and to provide a firm structure to the composite material. The shaper (extruder) units are arranged peφendicularly (at 90°). The worm feeder systems are equipped with frequency changers and function to transfer the filling masses of different colour and taste to a common extruder head through a divided pipe, therefore, the two masses can be filled in a wide variety of ratios or shaped many ways. Characterisation of the products Characterisation of the products was carried out in the laboratory of the Marcali Plant of Danone Hungary Kft. and by the Department of Dairy Farming, Institute of Agricultural and Food Sciences, University of Western Hungary. Table 1 (studies performed by Danone Hungary Kft.) shows the composition of two types of fresh cheese with different flavouring [simple sweet ("white mass") and chocolate ("chocolate mass")]. Table 1 Composition o>f the Composition of the white mass (*Vo) chocolate mass (%) Cutter Curd cheese 65.67 61.67 Butter 12.50 10.00 Dextrose 11.00 10.00 Sugar 8.00 7.00 Ultratex 4 2.50 0.00 Alta 2001 0.18 0.18 Potassium sorbate 0.15 0.15 Cocoa powder D21 0.00 5.00 Chocolate coating mass 0.00 6.00 Total: 100.00 100.00 Table 2 (studies performed by Danone Hungary Kft.) shows a comparison of a product of the invention, i.e. the pure fresh cheese of the curd cheese type ("curd cheese base") and fresh cheese with two flavours ("Duett Rudi", as herein exemplified), after the addition of butter and other additives ("finished product") with the corresponding existing product of Danone prepared by a method described in the examples in HU 217908 („natural types"). Table 2

As indicated in Table 2, the solids content of the curd cheese base (pure fresh cheese) in the product of the invention is significantly lower than the corresponding product produced by traditional methods. Upon addition of the additives, this difference is reduced in the white mass comparable to the existing product. Naturally, the chocolate mass has higher solids content as it contains higher amounts of additives. Table 3 (studies performed by the University of Western Hungary) shows average water activities of the pure fresh cheese before addition of butter (curd cheese base) in comparison with a product produced by traditional methods, as determined by column chromatography dew point measurement.

Table 3

Remarkably and suφrisingly, the product of the present invention has a decreased water activity even though it has reduced solids content, which clearly indicates that the homogeneous dispersion of high dispersivity quotient has higher water adsoφtion capacity. Table 4 (studies performed by the University of Western Hungary) shows a comparison of the physico-chemical properties of coextruded, enrobed dairy desserts of the invention and those of a fresh cheese of the curd cheese type prepared by traditional meth- ods (HU 217908). One of the coextruded products (Duett choc.) is prepared by coextruding a simple sweet and a chocolate-flavoured fresh cheese, and the other (D-VAN) is prepared by coextruding a simple sweet and a vanilla-flavoured fresh cheese.

Table 4 RESULTS OF PHYISICO-CHEMICAL ANALYSES

Tables 5a, 5b, 5c and 5d (studies performed by the University of Western Hungary) shows a comparison of the results of penetrometer analyses obtained for the products of the invention referred to in Table 4 with those obtained for a curd cheese type fresh cheese prepared by traditional methods (HU 217908). During the measurements, a sphere with a diameter of 1.5 cm was placed above the product to be tested, and penetration was measured for 5 s by engine-driven impression.

Table 5a RESULTS OF THE PENETROMETER ANALYSIS AT 6°C OF PRODUCTS WITH CHOCOLATE COATING

Table 5b RESULTS OF THE PENETROMETER ANALYSIS AT 6°C OF PRODUCTS WITH THE CHOCOLATB COATING REMOVED

Table 5c RESULTS OF THE PENETROMETER ANALYSIS AT 21°C OF PRODUCTS WITH CHOCOLATE COATING

Table 5d RESULTS OF THE PENETROMETER ANALYSIS AT 6°C OF PRODUCTS WITH THE CHOCOLATE COATING REMOVED

Tables 5a, 5b, 5c and 5d indicates that the products of the invention without chocolates coating have higher penetration than the traditional products at all temperatures tested, which is indicative of the creamy texture; nevertheless, the products had stable shape. Thus, they were plastic. Example 5 Preparation of the coating Upon base-freezing, traditional "chocolate curtain" immersion is applied to obtain complete coatings of the products with a wide variety of colours and taste harmony. Clearly, the colour compositions of the fillings of the divided products should be taken into consideration. Upon obtaining a complete coating, a cooling tunnel is used, followed by a second immersion. The second immersion is carried out by an elevated base-coating, i.e. without applying the "chocolate curtain" method. The coating may cover 50%, 20%, 30%, 40% or 70%), etc., of the slices, and matches the colours of the filling Congealation of the two types of coatings are carried out in a cooling tunnel of continuous operation. Thereafter, the product is packaged, parceled, baled and stored in cold-stores. These steps do not touch the merit of the invention. Table 6 (studies performed by Danone Hungary Kft.) shows the composition of a dairy dessert ("Danone Duett Rudi") prepared by coextruding two types of fresh cheeses with different flavouring [simple sweet ("white mass") and chocolate ("chocolate mass")] and by applying double coating. Table 6 Finished product Composition of Composition of the white mass the chocolate (%) mass (%) Curd cheese 18.60 + 17.48 36.08 Butter 3.54 + 2.83 6.37 Dextrose 3,12 + 2.83 5.95 Sugar 2.27 + 1.98 4.25 Ultratex 4 0.71 + 0.00 0.71 Alta 2001 0.O5 + 0.05 0.10 Potassium sorbate 0.O4 + 0.04 0.08 Cocoa powder D21 0.O0 + 1.42 1.42 Chocolate coating 6.67 + 8.37 15.04 mass White coating mass 15.O0 + 15.00 30.00 Finished product 100.00

ADVANTAGES, INDUSTRIAL APPLICATION The homogeneous and plastic/extrudable fresh cheese of the present invention is particularly useful for preparing dairy desserts, as a cream cheese substitute, or, for example as spread. Actually, it can be advantageously used as a substitute for any types of known fresh cheeses, such as the English or American cottage cheese, the Italian "Ricotta" cheese, the French "fromage frais" or "creme frais", the German "Quark" or "Bauernkase", the Hungarian clumpy "curd cheese" and other curd cheese types from Central Europe (e.g. "tvorog", "tvaroh", etc.), in particular in any application where plasticity and homogeneous, creamy structures are preferred. In comparison with analogous products prepared by corresponding existing methods, fresh cheeses prepared by the intensive high-shear agitation method of the present invention are pastier, usually have a lower solids content but also a lower water activity and are characterised by longer shelf-life. To the fresh cheeses of the invention, additives and flavourings may be added; therefore, they are particularly useful as starting materials for fresh cheese preparations or desserts. They are plastic, and thus may be readily shaped; however, they can also be enrobed, which represents a great advantage as far as further processing is concerned.

Claims

1. A method for preparing acid-coagulated, fermented, fresh cheese with an extrudable and homogeneous texture by cutting, heating, pressing and agitating a fermented curd prepared from skimmed, homogenised, heat-treated milk, characterized in that: - pressing is continued to reach a solids content appropriate to obtain a cheese material convertable into a material of plastic texture by agitation, - after pressing, the pressed curd is subjected to intensive high-shear agitation in a non-pressure-tight receptacle equipped with a cutting and blending device, until reaching a substantially homogeneous texture, while after appropriate cooling, the temperature is set to a value which, on the one hand, prevents overheating of the cheese material and the associated damage to proteins, and, on the other hand, prevents overcooling or sudden cooling, which would lead to the formation of dehydrated protein particles, and - if desired, fat content of the resulting homogeneous cheese material is adjusted by adding a high-fat ingredient, - if desired, further additives are added to the said cheese material, then - optionally, said homogeneous cheese material is shaped, and - optionally, after shaping, said cheese material is enrobed. 2. The method of claim 1 wherein during cutting, heating and pressing of the curd its dehydration is substantially avoided. 3. The method of claim 1 or 2 wherein pressing is continued to reach a solids content of 35% to 50%. 4. The method of any of claims 1 to 3, wherein cooling is provided by using a cool, inert gas, and the curd is kept between 0°C and 50°C, preferably between 10°C and 34°C during high-shear agitation. 5. The method of any of claims 1 to A, wherein - a partly or fully homogenised milk having a 0.5% to 3.6% fat content is fermented, preferably in closed fermenters at a temperature from 22°C to 36°C using a pure mesophil starter culture, to reach a pH of 4 to 5, preferably 4.4 to 4.9, - the curd is cut, heated to 50°C to 80°C, then pressed, whereas dehydration of the curd is avoided by preventing contact with the air, - high shear agitation is carried out in a cutter equipped with a cutting unit apt for a speed of at least 1,000 rpm, or by providing at least an equivalent shearing effect, - any significant overrun of the cheese material is avoided during intensive agitation, thereby a fresh cheese of the curd cheese type is produced. 6. The method of claim 5 wherein high-shear agitation is carried out in a cutter equipped vith a knife cutting unit and a scraper device for 0.5 to 60 minutes, preferably for 1 to 30 minutes, more preferably for 2 to 20 minutes, and highly preferably for 5 to 12 minutes, using knives or knife pairs with a total length of 0.1 to 2 m, preferably with a total length of 0.2 to 1 m, at a speed of 1,000 to 6,000 rpm, preferably 2,000 to 5,000 rpm, and more preferably 2,5 O0 to 4,000 rpm, wherein preferably the minimal distance between the endpoints of the knives external to their axis of rotation and any other element of the cutter is less than 100 mm, preferably less than 60 mm; or agitation is carried out at a shearing effect equivalent to that determined by any combination of the above conditions. 7. The method of claim 5 or 6, wherein - the curd is cut to pieces larger than pea-size, preferably to pieces, e.g. to cubes, with a size ranging from 2 to 10 cm, highly preferably from 3 to 6 cm, then - -heated to 65°C to 75°C, highly preferably to 7O° to 72°C and pressing of the cut and heated curd is carried out preferably at this temperature range, - pressing is carried out in two steps, wherein pressing in the first step is carried out under the whey and pressing in the second step is carried out in a closed system where whey is allowed to drain, and pressing is continued to reach a solids content of 35%> to 48%, preferably of 37% to 46% and more preferably to 38% to 43%. 8. The method of any of claims 5 to 7, wherein - the inert gas has a temperature of -40°C to -16O°C, - the inert gas is introduced into the cheese material near the knives, and - overrun is avoided by allowing the system to have a pressure not more than slightly, i.e. by 0.1 to 0.5 bar above atmospheric and nitrogen is optionally removed so as to prevent an increase in pressure, and highly preferably atmospheric pressure is applied. 9. The method of claim 8, wherein the overrun during intensive agitation is not more than 10%>, more preferably not more than 7%, and highly preferably not more than

0. The method of any of 1 to 9, wherein after intensive agitation fat content is adjusted preferably by adding butter. 11. The method of any of 1 to 10, wherein the fat content is adjusted to between 1% and 30%>, preferably to between 2%o and 25%, more preferably to between 5%) and 22%) or about 9%) and 22%) of the total mass of the cheese material. 12. The method of any of 1 to 11, wherein intensive agitation is followed by the addition of other additives to the cheese material, preferably dextrose, sucrose, K-sorbate and/or flavourings, such as vanilla, coconut, cocoa, chocolate, fruit, coffee or other types of flavourings of the same taste, and optionally still further additives. 13. The method of any of claims 1 to 12, wherein the cheese material having a homogeneous texture is shaped by extrusion. 14. The method of claim 13, wherein at least two kinds of cheese material with different composition or flavouring or one cheese material and one milky cream are coextruded, or the material(s) is (are) extruded together with other materials, such as fruit gel. 15. The method of claim 13 or 14 wherein, after extrusion, the extruded material is cut and then enrobed with a coating mass. 16. The method of any of claim 1 to 15 wherein the cutter is a cutter of any of claims 32 to 39. 17. An acid-coagulated, fermented fresh cheese which, at atmospheric pressure and at least at one temperature selected from 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C,

35°C and 40°C, is plastic and has homogeneous texture, and contains gaseous material not more than 5% per volume, preferably not more than 1%) per volume. 1 8. The fresh cheese of claim 17 which is plastic and extrudable in any of the temperature ranges selected from 10°C to 14°C, 14°C to 19°C, 19°C to 23°C, 23°C to 27°C, 27° C to 31°C; preferably, is plastic and extrudable at least between 19°C and 23 °C. 1 9. A fresh cheese obtainable by the method of any of claims 1 to 15. 20. The fresh cheese of any of claims 17 to 19 which is of the curd cheese type. 2 1. The fresh cheese of any of claims 17 to 20 wherein said cheese shows higher penetration in a penetrometer test than a control product prepared using the same method but without high-shear agitation. 22. The fresh cheese of any of claims 17 to 21, wherein said cheese has lower water actrvity than a control product prepared using the same method but without high-

23. The fresh cheese of claim 22 wherein said cheese has a water activity between 0.90 and 0.95, preferably between 0.91 and 0.94. 24. An acid-coagulated, fermented fresh cheese preparation, which is produced by mixing: - pure fresh crxeese, in a ratio of 40%> to 98%, - dietary fat, preferably butter or butter substitute, in a ratio of 2% to 20%> and, if desired, - other additives, and optionally - dextrose, in a ratio of 0% to 20%) - sugar, in a ratio of 0%> to 18% - one or more other additives, e.g. K-sorbate, texture improvers, spices, etc., in a ratio of0% to 6% and which, at atmospheric pressure and at least at one temperature selected from 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C and 40°C, is plastic and has a homogeneous texture. 25. The fresh cheese or fresh cheese preparation according to any of claims 17 to 24 which is flavoured. 26. The fresh cheese or fresh cheese preparation according to claim 25, compris- ing, as a flavouring, vanilla, coconut, cocoa, chocolate, fruit, coffee or other types of flavourings of the same taste, and optionally comprises other additives. 27. A fresh cl eese preparation obtainable by further processing of the fresh cheese of any of claims 17 to 23, wherein the ratio of pure fresh cheese in the fresh cheese preparation is between 20% and 50%, preferably between 30%> and 50%. 28. A dairy dessert obtainable from the fresh cheese or fresh cheese preparation of any of claims 17 to 27. 29. The dairy dessert of claim 28, preparable by shaping or extruding the fresh cheese or fresh cheese preparation. 30. The dairy dessert of claim 29, preparable by the coextrusion of at least two different types of fresh cheese preparation of any of claims 24 to 27, for example, of at least two fresh cheese materials or fresh cheese preparations with different flavouring. 31. The dairy dessert of any of claims 28 to 30 enrobed by coating mass.

32. An apparatus of batch operation, particularly designed to cut and blend food materials of soft consistency, comprising a receptacle with a closable lid, and an engine- driven knife cutting unit arranged in the receptacle, characterized in that it is further equipped with at least one jamming worm feeder (8) embedded in a housing (9), attached to the receptacle from outside, arranged to provide direct communication with the inner space of the receptacle through an opening in the wall of the receptacle to allow feeding into and removal from the receptacle of the required material(s). 33. The apparatus of claim 32, characterized in that the receptacle is a drum (1) with a cylindrical wall, and has a front lid (2) and a rear lid (2') in opposite arrangement, and preferably, the axis of the drum (1) is substantially horizontal, and at least one jamming worm feeder (8) is attached to the lower part of the drum (1), and the opening in the wall of the drum (1) is arranged at the lower part of the drum wall. 34. The apparatus of claim 33, characterized in that it is further equipped with a scraper unit capable of scraping the wall of the drum (1). 35. The apparatus of claim 34 characterized in that the scraper unit, the knife cutting unit and at least one j amming worm feeder (8) are equipped with individual driving units (4, 6 10). 36. The apparatus of any of claims 32 to 35, characterized in that the drum (1) is a stainless steel drum, the knife cutting unit comprises a shaft (7) and knife pairs (3), the scraper unit comprises a shaft (7¹) and a scraper (5), the shaft (7') of the scraper unit runs through the front lid (2) of the stainless steel drum (1), and the shaft (7) of the knife cutting unit runs through the rear lid (2'), the front lid (2), through which the shaft (7') of the scraper unit runs, can be opened and closed, the jamming worm feeders (8) are arranged in pairs, are mounted in individual housings (9), and optionally, the apparatus comprises only one pair of jamming worm feeders (8), the driving unit of the jamming worm feeders (10) drives one or more jamming worm feeders (8), the driving units of the jamming worm feeders (10), the driving unit of the scraper unit (6) and/or the driving unit of the knife cutting unit (4) are electric motors, preferably electric motors with regulable speed, preferably electric motors controlled by frequency changer. 37. The apparatus of claim 36, characterized in that the shaft (7) of the knife cutting unit is arranged eccentrically, under the axis of the drum (1). 38. The apparatus of claim 36 or 37, characterized in that the diameter of the stainless steel drum (1) is 0.2 to 2 m, preferably, 0.5 to 1 m, and the length of the Icnife pairs (3) is 0.1 to 1.5 m per pair, preferably 0.25 to 0.6 m per pair, and the minimal distance between the arc of circle defined by the rotational motion of the endpoints of the knife pairs (3) and the at least one jamming worm feeder (8) is less than 200 mm, prefera- bly less than 100 mm, and highly preferably is between 20 and 60 mm. 39. The apparatus of any of claims 36 to 38, characterized in that the number of the knife pairs (3) is one to five, preferably two to four, and the distance between individual knife pairs is 10 to 200 mm, preferably 30 to 100 mm, only one pair of jamming worm feeders (8) is attached to the apparatus, and the driving unit of the knife cutting unit (4) is an electric motor with a nominal capacity of 25 to 100 kW, preferably 30 to 80 lcW or 40 to 60 kW.