Method for producing fresh cheese and / or quark

Abstract

The invention relates to a method for producing quark (131) and / or fresh cheese, said method comprising at least the following steps: A providing a sour whey (100); B providing a milk-based thickened curdling product (42); C concentrating the sour whey (100) to a dry substance content of at least 80% of the dry substance content of the curdling product (42); D adding the concentrated sour whey (100) to the curdling product (42), providing a soured quark (131) or fresh cheese.

Description

[0001] METHOD FOR PRODUCING CREAM CHEESE AND / OR QUARK

[0002] The present invention relates to a process for producing cream cheese and / or quark.

[0003] There are known processes for producing quark in which additional acidulants, such as glucono-delta-lactone, are added to create a sour taste. These additives do not originate natively from the starting product, such as fermented milk or milk, and therefore must be declared. In addition to the intended pH reduction, these acidulants also affect the flavor and do not produce the desired taste.

[0004] A second method for producing quark involves the addition of cultures, which, however, require maturation to achieve the desired pH value. This typically has to be done in a batch process, making continuous quark production impossible.

[0005] Based on the aforementioned prior art, it is the object of the present invention to provide a process which enables the continuous, i.e. ongoing, production of quark, in which the quark acquires the most natural taste possible.

[0006] To enhance the taste, the pH value of the quark should preferably be reduced to a pH value of more than 3.5 and less than 5.0.

[0007] The present invention solves this problem by providing a method having the features of claim 1.

[0008] The process according to the invention relates to the production of quark and / or cream cheese. This also includes the production of double cream cheese, cream cheese, and / or HD quark.

[0009] The procedure includes at least the following steps:

[0010] A Provision of a sour whey;

[0011] The preparation of the sour whey can be done in a separate process, and the sour whey can be stored temporarily in a cooled environment. The same applies to step B. B: Preparation of a milk-based curdling product;

[0012] The provided milk-based curd product and the provided acid whey can have the same origin in the same milk fraction, thus enabling particularly time-, energy-, and / or material-efficient processing. However, this is not mandatory within the scope of the present invention. Milk-based includes any type of milk, such as cow's milk, goat's milk, and / or sheep's milk.

[0013] C Concentration of the acid whey to a dry matter content of at least 80% of the dry matter content of the coagulation product;

[0014] However, due to legal requirements and taste acceptance, sour whey cannot be used directly in the production of quark or cream cheese, especially non-acidified quark or cream cheese. Therefore, the sour whey must be concentrated, which removes a large amount of the water component.

[0015] D Addition of the concentrated acid whey to the coagulation product to produce a soured quark or cream cheese.

[0016] Finally, the concentrated acid whey is added to the prepared coagulation product, especially in combination with mixing.

[0017] Further advantageous embodiments of the method according to the invention are the subject of the subclaims.

[0018] It is advantageous if the provision of the acid whey comprises at least a centrifugal separation of a milk-based suspension into the acid whey and the coagulation product, whereby the acid whey obtained by the separation is concentrated and recycled into the coagulation product in step D. This recycling enables timely and particularly gentle processing of the product, without storage-related changes affecting the flavor.

[0019] The provision of the sour whey in step A also includes at least the following further steps:

[0020] Aa Providing milk or vat milk; Ab adding lactic acid bacteria to thicken the starting product and form the milk-based suspension with the coagulation product and the sour whey;

[0021] Ac Centrifugal separation with separation of the acid whey from the coagulation product.

[0022] The separated acid whey can then be concentrated and recycled into the coagulation product. This recycling is particularly advantageous, but not mandatory.

[0023] The coagulation product separated from the suspension may advantageously comprise more than 80% by weight of casein.

[0024] In order to avoid denaturation of the whey proteins and precipitation of these denatured proteins and thus a change in the taste of the product, it is advantageous if, after the preparation of the sour whey in step A, no thermal heating above 50°C takes place until the preparation of the soured curd.

[0025] To achieve a particularly fresh taste, it is advantageous if no additional sweet whey is added to the sour whey provided or to the coagulation product in steps BD.

[0026] In order to reduce the process effort and to obtain a product with as little processing as possible, it is advantageous if the steps AD are immediately consecutive steps.

[0027] It is also advantageous if the sequence of steps AD is carried out in such a way that whey proteins are predominantly dissolved in the curd, preferably at more than 90% by weight, based on the whey protein content. This results in a protein-rich and particularly natural-tasting end product.

[0028] The pH of the suspension after coagulation is preferably less than pH 4.8, preferably less than pH 4.5.

[0029] The pH of the concentrated sour whey is lower, preferably at least 0.2 lower, than the pH of the sour whey provided in step A. This means that not only the solids content but also the lactic acid component of the sour whey is concentrated, thereby lowering the pH.

[0030] The concentration of the acid whey in step C may include filtration as a partial step in combination with other measures, or may be carried out by filtration as the sole means of concentration in this step.

[0031] Preferably, the filtration is designed as a nanofiltration, which allows a particularly efficient concentration of both the solids and lactic acid.

[0032] Nanofiltration can be carried out using a filter system that has a filter membrane with an average pore size of less than 4 nm, preferably between 1 -3 nm.

[0033] The centrifugal separation in step Ac can advantageously be carried out using a centrifugal separator with a vertical axis of rotation, preferably a nozzle separator. This achieves a comparatively high separation efficiency.

[0034] The concentration in step C can advantageously be carried out to more than three times the dry matter content of the sour whey.

[0035] After the acid whey has been returned, in particular by mixing it with the coagulation product, the curd or cream cheese thus acidified can be cooled before its packaging.

[0036] The processing of the coagulation product into acidified quark or acidified cream cheese after the centrifugal separation in step 1-c can be carried out without the addition of further acidifying agents, apart from the recycled concentrated acid whey.

[0037] Advantageously, between steps 1-a and 1-b, and preferably after an optional homogenization, which is carried out in particular in the case of milk, heating to more than 80°C, preferably between 82-95°C and also preferably in less than 10 min, particularly preferably in 3-8 min.

[0038] Following heating, cooling takes place before the addition of the lactic acid bacteria to create optimal conditions for the aforementioned bacteria. Further advantages, features, and details of the invention will emerge from the following description, in which several exemplary embodiments of the invention are explained in more detail with reference to the accompanying figures. Those skilled in the art will expediently consider the features disclosed in the figures, the description, and the claims individually and combine them into useful further combinations. They show:

[0039] Fig. 1 Process diagram for discussing an embodiment of a method according to the invention.

[0040] Fig. 1 shows a schematic representation of a possible process flow within the scope of the present invention.

[0041] The aim is to achieve acidification without adding foreign substances.

[0042] The starting material of the process according to the invention is a sour whey 100, which is obtained from a milk 1, typically with approximately 3.5 wt.% fat, or from vat milk 2 in several preparatory steps.

[0043] The sour whey typically has a dry matter content of between 5-7%. Sour whey 100 obtained during quark production is typically discarded, while the quark fraction obtained from the sour whey is further processed into the final product, an acidified quark, by adding the acidifying agents or cultures mentioned above. Within the scope of the present invention, instead of the aforementioned substances, the sour whey 100 obtained during the production process of the quark fraction 42 is used to acidify it. The quark fraction corresponds to a coagulation product. A coagulation product can also be cream cheese.

[0044] However, acid whey 100 has a solids content more than 40% lower than curd fraction 42. Dilution of the curd fraction is undesirable, as it affects the consistency of the product and thus ultimately the quality of the final product.

[0045] The sour whey 100 is therefore concentrated to a dry matter content of at least 80% of the dry matter content of the quark fraction before being added to the quark fraction 42. Particularly preferably, the sour whey 100 can be concentrated by filtration by at least twice, preferably even three times, this amount. This occurs during filtration 90, preferably by means of nanofiltration. Water with a low acid content is separated from the sour whey 100 as filtrate 91, while the solids and the majority of the natural acids contained in the sour whey remain in the concentrated retentate 140 even after filtration. A particularly efficient separation of the filtrate from the retentate is achieved by the aforementioned nanofiltration.

[0046] During filtration, it is also possible to pass the retentate 140 through the filtration system several times to concentrate it until the target dry matter content is reached.

[0047] The dry matter content of the retentate can be determined by a density measurement, e.g. by using a Coriolis flow meter, which also determines the flow velocity, i.e. the speed at which the retentate is passed along the filtration surface.

[0048] After reaching a target value for the dry matter content, the concentrated retentate or the concentrated acid whey 150 can be added back to, or preferably returned to, the curd phase or the coagulation product 42 in a further step 120 to adjust the flavor. The amount of added retentate 140 is adjusted such that the pH of the acidified curd phase is adjusted to between pH greater than 3.5 and pH less than 5.5, preferably between pH 4.3 and 4.8.

[0049] This addition or return of the concentrated retentate 140 may be accompanied by intensive mixing.

[0050] In a further step 130, the product can then optionally be cooled and packaged as acidified quark 131.

[0051] The extraction of sour whey 100 can preferably be carried out according to the following steps:

[0052] The starting product for the preparation of sour whey 100 is a vat milk 1 or a milk 2, typically with a fat content between 3-4 wt.% fat, preferably between 3.5 and 3.8 wt.% fat. In the case of milk 2, homogenization 10 is first carried out at pressures of more than 100 bar, preferably between 150-200 bar, particularly preferably between 170-180 bar.

[0053] The homogenization 10 is preferably carried out at temperatures of more than 40°C, preferably between 50-60°C.

[0054] Then, both starting materials 1 and 2 are heated to more than 80°C, preferably between 82-95°C. The heating takes place in less than 10 minutes, in particular 3-8 minutes.

[0055] Subsequently, the heated intermediate product is cooled 30 to a growth temperature, preferably below 50°C, particularly preferably below 40°C.

[0056] Bacteria 41 are then added 40, forming lactic acid-precipitated milk protein, essentially casein. A coagulation product 42 and acid whey 100 are formed as a suspension 43.

[0057] This formation of the suspension occurs by coagulation 50 at a pH value in the range of pH = 4.4 to 4.8.

[0058] In the case of boiler milk as the starting material (left process flow in Fig. 1 ), the starting product and accordingly also the intermediate products are processed with only traces of.

[0059] In the case of milk, a higher temperature of more than 50°C, preferably 55-65°C, is required before separating the coagulation product 42 and acid whey 100 due to its higher viscosity. For this purpose, appropriate heating 60 is performed. The fat is virtually homogenized on the casein as its carrier by heating 60, so that it is carried out on the solid phase during the subsequent separation. The added culture or bacteria can be at least partially heat-damaged / killed at the high temperature.

[0060] Between approximately 3.5% and approximately 8% of the curd's milk, there is a separation gap. Up to 3.5% of the curd, the curd is the heavy phase of mechanical separation. The cheese is removed via nozzles on the solids side of a centrifugal clarifier, and whey is the light, clear phase. From approximately 7%, the curd is the light phase and is removed on the light liquid phase side of a clarifier or separator. Whey is the heavy phase. The standard product is, for example, double cream cheese. The separator or clarifier is designed, in particular, as a nozzle separator with a plate stack inside the drum.

[0061] Subsequently, mechanical separation 70 takes place in the centrifugal field of a centrifugal separator. This separates acid whey 100, which is then concentrated as described above and can be returned to the coagulation product.

[0062] Concentration is necessary because quark and cream cheese are subject to strict regulations regarding dry matter content. Adding acid whey without prior concentration would result in dilution, meaning the product would no longer meet the prescribed standards. Only through concentration can the acid whey be used as a flavor enhancer for the product.

[0063] Furthermore, acidifying the curd by adding a certain amount of the previously separated sour whey would have only a minor effect due to the lactic acid content. This is another reason why concentration has another advantage.

[0064] Concentrating the acid whey 100 to approximately the dry matter content of the curd also allows for a higher concentration of lactic acid in the acid whey concentrate. Adding and preferably returning this concentrated acid whey 140 to the quark or cream cheese thus significantly reduces the pH and also achieves the desired flavor effect in the quark product.

[0065] It is not necessary to label the whey as an additive as long as it comes from the same base.

[0066] Various methods are available for concentration, such as filtration and, particularly preferred, nano-filtration.

[0067] Separation is preferably based on molecular weight and / or molecular size. Lactic acid cannot penetrate the filtration system's membrane quantitatively to the same extent as water. The retention factor does not necessarily have to be 100%, but it must be sufficiently large that water penetrates the membrane more easily than lactic acid. A preferred membrane can have an average pore size between 1 and 3 nm, preferably between 1.5 and 2.5 nm. The pore size can be determined optically, with the average pore size referring to a correspondingly representative-sized section of the filter membrane's membrane wall.

[0068] The process according to the invention is therefore a combination of concentrating the sour whey taking into account the desired product properties and returning this concentrate to the curd.

[0069] Quark or cream cheese are typically produced by separating milk and whey that have been "curdled" using cultures. The cultures achieve a pH of approximately 4.5, at which the casein has its isoelectric point and is thus optimally separated. A jet separator serves as the separation machine, separating the casein—mixed with a small amount of whey—through the jets as the heavy phase. The whey, which contains a dry matter content of approximately 6% and a certain amount of lactic acid, is separated via the light phase.

[0070] This process processes sour whey, which is discarded in the current process. Dairy companies have previously viewed the utilization of sour whey as rather problematic. Thus, several million liters are disposed of as waste in the dairy industry every year. This process enables the use of sour whey as a very interesting and rich intermediate product.

[0071] Reference symbol

[0072] 1 milk

[0073] 2 kettle milk

[0074] 10 Homogenization

[0075] 20 Warming

[0076] 30 Cooling

[0077] 40 Addition of bacteria

[0078] 41 bacteria

[0079] 42 Coagulation product

[0080] 43 Suspension

[0081] 50 Coagulation

[0082] 60 Heating

[0083] 70 mechanical separation

[0084] 90 Filtration

[0085] 91 filtrate

[0086] 100 sour whey

[0087] 120 Addition of concentrated sour whey

[0088] 130 Cooling and packaging

[0089] 131 acidified quark

[0090] 140 concentrated sour whey

Claims

Patent claims 1 . A process for producing quark (131) and / or fresh cheese comprising at least the following steps: A Provision of a sour whey (100); B Provision of a milk-based thickened coagulation product (42); C Concentration of the acid whey (100) to a dry matter content of at least 80% of the dry matter content of the coagulation product (42); D Addition of the concentrated acid whey (100) to the coagulation product (42) to provide a soured curd (131) or cream cheese.

2. Method according to claim 1, characterized in that the provision of the acid whey (100) comprises at least one mechanical separation (70), preferably a centrifugal separation, of a milk-based suspension (43) into the acid whey (100) and the coagulation product (42), wherein the acid whey (100) is concentrated and returned to the coagulation product (42) in step D.

3. Method according to claim 1 or 2, characterized in that the provision comprises at least the following further steps: Aa Providing milk (1 ) or kettle milk (2); From the addition (40) of lactic acid bacteria (41) with thickening of the starting product (1 or 2) to form the milk-based suspension (43) with the coagulation product (42) and the sour whey (100); Ac mechanical separation, preferably centrifugal separation, with separation of the acid whey (100) from the coagulation product (42).

4. Method according to one of the preceding claims, characterized in that the coagulation product (42) separated from the suspension (43) comprises more than 80 wt.% casein.

5. Process according to one of the preceding claims, characterized in that after the provision of the sour whey in step A, no thermal heating above 50°C takes place until the provision of the soured curd.

6. Process according to one of the preceding claims, characterized in that in steps BD no additional sweet whey is added to the sour whey provided or to the coagulation product in steps BD.

7. Method according to one of the preceding claims, characterized in that the steps AD are immediately consecutive steps.

8. Method according to one of the preceding claims, characterized in that the sequence of steps AD is carried out in such a way that whey proteins are predominantly dissolved in the curd, preferably to more than 90% by weight, based on the amount of whey protein contained.

9. Method according to one of the preceding claims, characterized in that the pH value of the suspension (43) is less than pH=4.8, preferably less than pH=4.

5.

10. Method according to one of the preceding claims, characterized in that the pH of the concentrated acid whey (140) is lower, preferably at least 0.2 lower, than the pH of the acid whey (100) provided in step A.

11. Method according to one of the preceding claims, characterized in that the concentration of the acid whey (100) in step C comprises a filtration (90) or is carried out by a filtration (90).

12. The method according to claim 7, characterized in that the filtration (90) is designed as a nanofiltration.

13. The method according to claim 8, characterized in that the nanofiltration is carried out by means of a filter system which has a filter membrane with an average pore size of less than 4 nm, preferably between 1-3 nm.

14. The method according to any one of the preceding claims, characterized in that the centrifugal separation in step Ac is carried out by a centrifugal separator with a vertical axis of rotation, preferably by a nozzle separator.

15. Method according to one of the preceding claims, characterized in that the concentration in step C is carried out to more than three times the dry matter content of the sour whey (100).

16. Method according to one of the preceding claims, characterized in that after recirculation (120) of the sour whey (100), in particular by mixing with the coagulation product, cooling (130) of the curd (131) or fresh cheese thus acidified takes place.

17. Method according to one of the preceding claims, characterized in that the processing of the coagulation product (100) after the mechanical separation (70) in step 1-c, apart from the recycled concentrated acid whey (140), takes place without the addition of further acidifying agents.

18. Method according to one of the preceding claims, characterized in that between steps 1-a and 1-b, and preferably after an optional homogenization (10), heating (20) to more than 80°C, preferably between 82-95°C and likewise preferably in less than 10 min, particularly preferably in 3-8 min, takes place.

19. Method according to claim 14, characterized in that following the heating (20) a cooling (30) takes place before the addition (40) of the lactic acid bacteria (41).

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