Cheese capable of automatically separating whey and preparation method of cheese

Abstract

The invention belongs to the technical field of dairy product preparation, and discloses cheese capable of automatically separating whey and a preparation method thereof, the preparation method comprises the following steps: enzymolysis treatment: adding 0.003-0.01 part of alkaline protease and 0.001-0.003 part of chymosin into 99-100 parts of cow milk, uniformly mixing, and carrying out enzymolysis for 15-35 minutes at the temperature of 48-55 DEG C to obtain an enzymolysis protein base material; and fermenting: inoculating a leavening agent in the enzymolysis protein base material, the leavening agent comprises 0.001-0.01 part of a strain C-1 and 0.001-0.005 part of a strain PRIME 800, and fermenting after uniformly stirring. Through mutual cooperation and interaction between the raw materials and the process, automatic separation of whey is realized instead of manual or equipment whey removal, the process of independently removing whey is omitted, the equipment requirement is low, the cheese does not use a thickening agent, an emulsifying agent, a stabilizing agent, a sweetening agent, a coloring agent and the like, the effect of the cheese can be achieved by adopting the combination of common raw materials, and the cheese has a good market prospect. The texture is fine and the surface is smooth.

Description

Technical Field

[0001] The invention relates to the technical field of dairy product preparation, in particular to cheese with automatic whey separation and a preparation method thereof. Background Art

[0002] Cheese has quietly become a new favorite in the food consumption industry due to its nutritional and health properties. The demand is growing, and the cheese production is also showing a steady growth trend. The preparation of cheese is mainly based on large-scale cheese processing enterprises and ethnic cheese food processing. The varieties of large-scale cheese processing enterprises are mainly fresh cheese and hard cheese. Ethnic cheese food processing is mainly distributed in Inner Mongolia, Xinjiang, Tibet, Yunnan, Guangdong and other places, mainly producing milk tofu, milk lumps, Qula, milk fan, milk cake, etc.

[0003] Whether it is large-scale production or ethnic cheese, the cheese preparation process needs to go through the whey drainage process. The method of whey drainage is to use rennet to promote milk coagulation, use mechanical equipment such as cutters and stirrers to process milk, promote protein and fat coagulation, and cause whey separation. In some cases, a centrifuge is used to accelerate the separation of whey and curd by generating strong centrifugal force. Ethnic cheese uses manual whey separation. The difference between large-scale production and ethnic cheese is that some large mechanical equipment such as cutters, stirring equipment, centrifuges, etc. are used when draining whey. Patent Publication No. CN116784390A discloses a method for preparing a live bacteria sucking cheese. The whey drainage process is: using rennet to promote milk coagulation, stirring and breaking the milk until there is no obvious curd block, and the curd and whey are evenly mixed; centrifugation to separate whey and curd, the centrifugal force is 2000-6000g, the time is 2.5-30min, the temperature is 5-40℃, and the water content of the curd is 70-85%.

[0004] From the above, we can see that although cheese with higher dry matter content can be obtained by separating whey by equipment or manually, the whey removal process is complicated, the manual separation efficiency is low, and the investment in large-scale equipment is large. With the increasing consumption of cheese, it is urgent to simplify the process, give cheese new quality productivity, use the equipment and process of other products to realize cheese preparation, and innovate a Chinese cheese processing model with Chinese characteristics and its preparation method. Summary of the invention

[0005] The invention aims to overcome the problems of complicated whey removal process, low manual separation efficiency and large investment in large-scale equipment in the existing cheese preparation, and provide a cheese with automatic whey separation and a preparation method thereof. By selecting fermentation bacteria, optimizing the fermentation process, optimizing the enzymatic hydrolysis process, limiting the enzyme ratio and limiting the synergistic ratio of bacterial species, the cheese can achieve automatic whey separation in the package. The cheese preparation process is simple, the process of separate whey removal is omitted, the equipment requirement is low, the investment in traditional whey removal equipment is no longer required, and the cheese is easy to promote and apply.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] A method for preparing cheese with automatic whey separation, comprising:

[0008] Enzymatic hydrolysis: add 0.003-0.01 parts of alkaline protease and 0.001-0.003 parts of rennet to 99-100 parts of milk, mix well, and perform enzymatic hydrolysis at a temperature of 48-55° C. for 15-35 minutes to obtain an enzymatic protein base material;

[0009] Fermentation: inoculate a fermentation agent into the enzymatic protein base material, the fermentation agent includes 0.001-0.01 parts of strain C-1 and 0.001-0.005 parts of strain PRIME 800, stir evenly and then ferment.

[0010] In the technical scheme of the present invention, the cheese with automatic whey separation is prepared by first adding alkaline protease and rennet to cow's milk, enzymolyzing it at a temperature of 48 to 55°C for 15 to 35 minutes, and then fermenting the enzymolyzed protein base material. The fermentation is prepared by the synergistic fermentation of strain C-1 and strain PRIME 800. The present invention provides a method for preparing cheese with automatic whey separation. During the preparation process, the composition and ingredients of the raw materials are limited, such as the type and dosage of enzymes, the type and dosage of fermentation bacteria, and targeted adjustments. At the same time, enzymolysis is first performed and then fermented, and the enzymolysis process parameters (enzymolysis temperature, enzymolysis time, enzyme type and ratio) are limited. Through the mutual coordination and interaction between the raw materials and the process, automatic whey separation is achieved, rather than manual or equipment whey removal, eliminating the process of separate whey removal, low equipment requirements, and no longer need to invest in traditional whey removal equipment to save a process link. The cheese does not use thickeners, emulsifiers, stabilizers, sweeteners, colorants, etc., and a combination of common raw materials can achieve the cheese effect, with fine texture and smooth surface; at the same time, the preparation process is simple, the equipment requirements are low, and it is easy to promote and apply.

[0011] As a preferred embodiment of the present invention, the protein content in cow's milk is 3.5wt% to 3.8wt%.

[0012] As a preferred embodiment of the present invention, the ratio of alkaline protease to chymosin added is 4-2.5:1. Alkaline protease and chymosin have a synergistic effect. More preferably, the ratio of alkaline protease to chymosin added is 3:1.

[0013] As a preferred embodiment of the present invention, the enzymatic hydrolysis condition is 20-30 min at a temperature of 50-55° C. More preferably, the enzymatic hydrolysis condition is 20-30 min at a temperature of 50° C.

[0014] The strain C-1 is Streptococcus salivarius thermophilus subspecies C-1, which was isolated from homemade yak yogurt made by herders in Lebuchacuo, Daocheng County, Sichuan Province. It has a fast fermentation rate and shows good growth and acid production performance. The fermented milk prepared with strain C-1 has a distinct milky aroma and a delicate and smooth taste. The strain has been deposited in the General Microbiological Center of the China Microbiological Culture Collection Administration before the application, and the deposit number is CGMCC No.22113. The strain PRIME 800 is a Yo-Mix Prime series under the International Flavors and Fragrances Company (IFF). PRIME 800. The study found that compared with conventional strains, cheese made with strains C-1 and PRIME 800 had more outstanding texture, sensory and stability effects.

[0015] As a preferred embodiment of the present invention, the added strain C-1 is 0.002-0.005 parts, and the added strain PRIME800 is 0.0015-0.0025 parts. More preferably, the added strain C-1 is 0.005 parts, and the added strain PRIME 800 is 0.0025 parts.

[0016] As a preferred embodiment of the present invention, the ratio of the added strain C-1 to the strain PRIME 800 is 3 to 1.5:1, and more preferably, the ratio of the added strain C-1 to the strain PRIME 800 is 2:1. The strains C-1 and PRIME 800 can be used for cheese, and the effect of whey separation can be achieved by limiting the type, dosage and ratio of the enzymes and combining the preparation process.

[0017] As a preferred embodiment of the present invention, before the enzymatic protein base material is fermented, homogenization and sterilization are required. The homogenization temperature is 65° C. and the homogenization pressure is 200 bar. The homogenization process breaks the fat in the milk into fine fat droplets, prevents cream separation, improves the stability and shelf life of the emulsion, and makes the milk whiter. The sterilization adopts pasteurization method, the sterilization temperature is 95° C., and the sterilization time is 300 seconds. The pasteurization method is used to maintain the soft texture and high water holding capacity of the milk.

[0018] As a preferred embodiment of the present invention, after the starter is inoculated, the mixture is stirred evenly, the enzymolyzed protein base material is filled, and then fermented after filling. After the enzymolyzed protein base material is prepared, the mixture is inoculated, and after inoculation, the enzymolyzed protein base material is filled into a packaging bag of a cheese product, and fermented in the packaging bag to obtain a cheese product.

[0019] As a preferred embodiment of the present invention, the fermentation conditions are 37° C. to 40° C. for 4 to 8 hours to obtain cheese.

[0020] Another aspect of the present invention provides a cheese with automatic whey separation, wherein the cheese is prepared by the method for preparing the cheese with automatic whey separation.

[0021] As a preferred embodiment of the present invention, in the preparation method of cheese, before fermentation, the product has been filled into a packaging bag, and cheese is obtained after fermentation, and the cheese is automatically separated from whey in the packaging bag. After the whey is automatically separated, the whey can be used as a healthy, safe and nutritious product, and consumers can eat it as needed. In the cheese production process in the prior art, the whey is extracted by a centrifugal method after the whey is separated, so that the utilization rate of by-products such as whey is not high, and there are inevitably problems such as sewage treatment and environmental pollution in the subsequent whey discharge process. The cheese produced by the present invention does not discharge whey in the production stage, but is uniformly loaded into a packaging bag, and the whey is automatically separated in the packaging bag, which saves the process of discharging whey in the production process and realizes the comprehensive utilization of whey by-products.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention provides a method for preparing cheese with automatic whey separation. During the preparation process, the composition and ingredients of the raw materials are limited, such as the type and dosage of enzymes, the type and dosage of fermented bacteria are adjusted in a targeted manner, and enzymolysis is first performed and then fermented, and the enzymolysis process parameters (enzymolysis temperature, enzymolysis time, enzyme type and ratio) are limited. Through the mutual cooperation and interaction between the raw materials and the process, the automatic separation of whey is achieved, rather than manual or equipment whey removal, which saves the process of removing whey separately, has low equipment requirements, and no longer requires the investment of traditional whey removal equipment, which saves a process link. In addition, the cheese does not use thickeners, emulsifiers, stabilizers, sweeteners, colorants, etc., and the combination of common raw materials can achieve the effect of cheese, with fine texture and smooth surface; at the same time, the preparation process is simple, the equipment requirements are low, and it is easy to promote and apply.

[0024] 2. The invention provides cheese with automatic whey separation, which can automatically separate whey from cheese in a packaging bag. After the whey is automatically separated, consumers can eat it as needed, thereby saving the process of draining whey in the production process and realizing the comprehensive utilization of whey by-products. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The actual pictures are of cheese before automatic whey separation (A) and cheese after automatic whey separation (B) prepared by the method of the present invention;

[0026] Figure 2 The actual pictures of the cheese whey after separation of Comparative Example 5 (A), Example 5 (B), Example 1 (C), and Comparative Example 6 (D);

[0027] Figure 3 The molecular weight distribution diagram of the cheeses of Comparative Example 5 (10 min), Example 5 (20 min), Example 1 (30 min), and Comparative Example 6 (40 min);

[0028] Figure 4 It is a comparison chart of the whey precipitation height, whey proportion, whey protein content and protein content in cheese of Comparative Example 5 (10 min), Example 5 (20 min), Example 1 (30 min) and Comparative Example 6 (40 min); DETAILED DESCRIPTION

[0029] In order to more clearly describe the invention purpose, technical scheme and technical effect advantages in the specific implementation case of the present invention, the scheme in the specific embodiment will be described in detail in combination with the drawings of the specification of the present invention. The specific technical scheme involved in the following specific embodiments is only for a clear and complete description of the innovative technical scheme of the present invention. It is only a part of the specific implementation scheme that can be adopted by the present invention, not all embodiments, and should not be understood as a limitation on the innovative scheme of the present invention. Any scheme adopting the same inventive concept of the present invention should be included in the protection scope of the present invention.

[0030] Secondly, the description of the drawings in the specific embodiments of the present invention is only for the convenience of technical personnel to understand the solution of the present invention. The partial details in the drawings are for the convenience of clearly presenting the technical solution. It should not be considered that all technical features in the drawings must be included in the specific implementation cases, and the detailed features in the drawings should not be identified as additional limitations on the innovative technical solution of the present invention. The components in the various embodiments described and shown in the drawings can be combined and arranged according to different configurations, and these changes in combination and arrangement should be identified as part of the entire embodiment of the innovative solution of the present invention and included in the scope of protection of the present invention.

[0031] In summary, the schemes or descriptions presented in the specific embodiments and drawings of the present invention are not intended to limit the scope of protection claimed, but are merely selected embodiments / cases to help technicians understand the relevant innovative solutions. Based on these embodiments, all other equivalent or parallel embodiments obtained by those skilled in the art without creative work are within the scope of protection claimed by the present invention.

[0032] Example 1

[0033] The invention discloses a cheese with automatic whey separation. The cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.005 parts of bacterial strain C-1, and 0.0025 parts of bacterial strain PRIME 800. The protein in the cow's milk has a protein content of 3.8wt%, the rennet is derived from Kluyveromyces lactis, and the alkaline protease is derived from Bacillus licheniformis.

[0034] The cheese preparation method is:

[0035] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 50° C. for 30 minutes to obtain an enzymatically hydrolyzed protein base material;

[0036] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0037] (3) Cool the enzymatic protein base to 37°C to 40°C, inoculate strain C-1 and strain PRIME 800, stir evenly and then fill the enzymatic protein base, keep the temperature at 37°C to 40°C and ferment for 4-8 hours to obtain cheese. In the preparation process, after enzymatic hydrolysis, homogenization, sterilization, cooling, inoculation, and then online filling, the cheese is put into storage for fermentation and then cooled. The whey is automatically separated during the fermentation stage, that is, whey precipitation will gradually appear during the fermentation period. The cheese is not separated before the whey is Figure 1 (A), cheese after whey automatic separation Figure 1 (B).

[0038] Example 2

[0039] The invention discloses a cheese with automatic whey separation. The cheese is prepared by mixing the following raw materials by weight: 100 parts of cow's milk, 0.01 parts of alkaline protease, 0.003 parts of rennet, 0.005 parts of bacterial strain C-1, and 0.0025 parts of bacterial strain PRIME 800. The protein in the cow's milk has a protein content of 3.5wt%, the rennet is derived from Kluyveromyces lactis, and the alkaline protease is derived from Bacillus licheniformis.

[0040] The cheese preparation method is:

[0041] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 50° C. for 30 minutes to obtain an enzymatically hydrolyzed protein base material;

[0042] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0043] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0044] Example 3

[0045] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.0045 parts of strain C-1, and 0.003 parts of strain PRIME 800. The protein content in the cow's milk is 3.8wt%, the rennet is derived from Kluyveromyces lactis, and the alkaline protease is derived from Bacillus licheniformis.

[0046] The cheese preparation method is:

[0047] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 55° C. for 20 minutes to obtain an enzymatically hydrolyzed protein base material;

[0048] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0049] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0050] Example 4

[0051] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.0075 parts of alkaline protease, 0.003 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800. The protein content in the cow's milk is 3.8wt%, the rennet is derived from Kluyveromyces lactis, and the alkaline protease is derived from Bacillus licheniformis.

[0052] The cheese preparation method is:

[0053] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at 48° C. for 35 minutes to obtain an enzymatically hydrolyzed protein base material;

[0054] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0055] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0056] Example 5

[0057] The invention discloses a cheese with automatic whey separation. The cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.005 parts of bacterial strain C-1, and 0.0025 parts of bacterial strain PRIME 800, wherein the protein content in the cow's milk is 3.8wt%, the rennet is derived from Kluyveromyces lactis, and the alkaline protease is derived from Bacillus licheniformis.

[0058] The cheese preparation method is:

[0059] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 50° C. for 20 minutes to obtain an enzymatically hydrolyzed protein base material;

[0060] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0061] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0062] Comparative Example 1

[0063] A cheese with automatic whey separation, the cheese comprising the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800, wherein the protein content in the cow's milk is different from that in Example 1, and the protein content in this comparative example is 4.0wt%.

[0064] The preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0065] Comparative Example 2

[0066] A cheese with automatic whey separation, the cheese comprising the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800, wherein the protein content in the cow's milk is different from that in Example 1, and the protein content in this comparative example is 3.3wt%.

[0067] The preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0068] Comparative Example 3

[0069] The raw material ingredients of the cheese in this comparative example are the same as those in Example 1, but the preparation method is different. The other experimental parameters of this comparative example are the same as those in Example 1. The preparation method of the cheese in this comparative example is:

[0070] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 57° C. for 20 minutes to obtain an enzymatically hydrolyzed protein base material;

[0071] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0072] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0073] Comparative Example 4

[0074] The raw material ingredients of the cheese in this comparative example are the same as those in Example 1, but the preparation method is different. The other experimental parameters of this comparative example are the same as those in Example 1. The preparation method of the cheese in this comparative example is:

[0075] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 45° C. for 35 minutes to obtain an enzymatically hydrolyzed protein base material;

[0076] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0077] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0078] Comparative Example 5

[0079] The raw material ingredients of the cheese in this comparative example are the same as those in Example 1, but the preparation method is different. The other experimental parameters of this comparative example are the same as those in Example 1. The preparation method of the cheese in this comparative example is:

[0080] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 50° C. for 10 minutes to obtain an enzymatically hydrolyzed protein base material;

[0081] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0082] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0083] Comparative Example 6

[0084] The raw material ingredients of the cheese in this comparative example are the same as those in Example 1, but the preparation method is different. The other experimental parameters of this comparative example are the same as those in Example 1. The preparation method of the cheese in this comparative example is:

[0085] (1) enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and enzymatically hydrolyzing at a temperature of 50° C. for 40 minutes to obtain an enzymatically hydrolyzed protein base material;

[0086] (2) homogenizing and sterilizing the enzymatic protein base material at a homogenization temperature of 65° C., a homogenization pressure of 200 bar, a sterilization temperature of 95° C., and a time of 300 s;

[0087] (3) Cooling the enzymatic protein base to 37° C. to 40° C., inoculating strain C-1 and strain PRIME 800, stirring evenly, filling the enzymatic protein base, and fermenting at 37° C. to 40° C. for 4-8 hours to obtain cheese.

[0088] Comparative Example 7

[0089] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.0067 parts of alkaline protease, 0.0013 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800. The ratio of alkaline protease to rennet added is 5:1, which is different from Example 1. The preparation method of the cheese in this comparative example is the same as that in Example 1, and other raw material components and addition amounts are the same as those in Example 1.

[0090] Comparative Example 8

[0091] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.0048 parts of alkaline protease, 0.0032 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800. The ratio of alkaline protease to rennet added is 1.5:1, which is different from that in Example 1. The preparation method of the cheese in this comparative example is the same as that in Example 1, and other raw material components and addition amounts are the same as those in Example 1.

[0092] Comparative Example 9

[0093] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.01 parts of alkaline protease, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800. The alkaline protease used is the same as that in Example 1, but the amount of alkaline protease used is different. The protein content in the cow's milk is 3.8wt%. The preparation method of the cheese in this comparative example is the same as that in Example 1, and the other raw material components, that is, the addition amounts, are the same as those in Example 1.

[0094] Comparative Example 10

[0095] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.003 parts of rennet, 0.005 parts of strain C-1, and 0.0025 parts of strain PRIME 800. The rennet used is the same as that in Example 1, but the amount of rennet used is different, the protein content in the cow's milk is 3.8wt%, the preparation method of the cheese in this comparative example is the same as that in Example 1, and the other raw material components, that is, the addition amounts, are the same as those in Example 1.

[0096] Comparative Example 11

[0097] The cheese of this comparative example has the same raw material components as those of Example 1 except that no bacteria are added. The preparation method is different. The preparation method of the cheese of this comparative example is as follows:

[0098] (1) Enzymatically hydrolyzing the milk: adding alkaline protease and rennet to the milk, stirring and mixing evenly, and performing enzymatic hydrolysis at a temperature of 50° C. for 35 minutes to obtain an enzymatically hydrolyzed protein base material.

[0099] (2) Homogenization, sterilization, and cooling were performed according to the conditions of Comparative Example 1, but no bacteria were added subsequently, and there was no fermentation process. After sterilization, the mixture was directly cooled and filled. The other preparation methods and other parameters were the same as those of Example 1.

[0100] Comparative Example 12

[0101] The raw material ingredients of the cheese in this comparative example are the same as those in Example 1, but the preparation method is different. The other experimental parameters of this comparative example are the same as those in Example 1. The preparation method of the cheese in this comparative example is:

[0102] (1) homogenizing and sterilizing the milk at a homogenization temperature of 65°C, a homogenization pressure of 200 bar, a sterilization temperature of 95°C, and a time of 300 seconds;

[0103] (2) Cooling the milk to 37°C to 40°C, inoculating strain C-1 and strain PRIME 800, and maintaining the temperature at 37°C to 40°C for 4-8 hours;

[0104] (3) The fermented milk is subjected to enzymatic hydrolysis, alkaline protease and rennet are added, the mixture is stirred and mixed evenly, and the mixture is filled and enzymatic hydrolyzed at 50° C. for 30 minutes to obtain cheese.

[0105] Comparative Example 13

[0106] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.006 parts of strain C-1, and 0.0015 parts of strain PRIME 800. The ratio of the added strains is different from that in Example 1, and the ratio of strain C-1 to strain PRIME 800 in this comparative example is 4:1. The preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0107] Comparative Example 14

[0108] A cheese with automatic whey separation, the cheese is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.0042 parts of strain C-1, and 0.0033 parts of strain PRIME 800. The ratio of the added strains is different from that in Example 1, and the ratio of strain C-1 to strain PRIME 800 in this comparative example is 1.25:1. The preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0109] Comparative Example 15

[0110] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, and 0.01 parts of bacterial strain C-1. The added bacterial strain is different from that in Example 1, the preparation method of the cheese in this comparative example is the same as that in Example 1, and other experimental parameters of this comparative example are the same as those in Example 1.

[0111] Comparative Example 16

[0112] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, and 0.005 parts of bacterial strain PRIME 800. The added bacterial strain is different from that in Example 1, the preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0113] Comparative Example 17

[0114] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, 0.00375 parts of thermophilic streptococci, and 0.00375 parts of bulgaricus lactobacillus. The added strains are different from those in Example 1, the preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0115] Comparative Example 18

[0116] A cheese with automatic whey separation is prepared by mixing the following raw materials by weight: 99 parts of cow's milk, 0.006 parts of alkaline protease, 0.002 parts of rennet, and 0.0075 parts of plant lactobacillus. The added strains are different from those in Example 1, the preparation method of the cheese in this comparative example is the same as that in Example 1, and the other experimental parameters of this comparative example are the same as those in Example 1.

[0117] Test Example 1

[0118] This test example tests the whey precipitation height of Examples 1-5 and Comparative Examples 1-18. The whey precipitation height is measured from the bottom of the light green whey part to the bottom of the white cheese. The total amount of the test base material of all test groups is 500 mL, and the diameter of the container used for the test is 10 cm. After the test, the whey precipitation height results are shown in Table 1.

[0119] Table 1 Results of cheese whey precipitation height of Examples 1-5 and Comparative Examples 1-18

[0120] Serial number Whey separation height (mm) Example 1 38.7 Example 2 39.5 Example 3 37.5 Example 4 39.1 Example 5 38.3 Comparative Example 1 21.4 Comparative Example 2 45.5 Comparative Example 3 5.9 Comparative Example 4 20.5 Comparative Example 5 5.7 Comparative Example 6 42.1 Comparative Example 7 44.5 Comparative Example 8 21.5 Comparative Example 9 23.9 Comparative Example 10 0 Comparative Example 11 0 Comparative Example 12 22.3 Comparative Example 13 42.6 Comparative Example 14 25.4 Comparative Example 15 49.8 Comparative Example 16 17.8 Comparative Example 17 21.0 Comparative Example 18 52.3

[0121] The whey precipitation height can evaluate the effect of whey separation. If no whey is precipitated, the whey precipitation height is 0; if too little whey is precipitated, the precipitation height is less than 26mm, then sufficient whey separation is not achieved, resulting in a higher water content in the cheese; if too much whey is precipitated, the precipitation height is greater than 40mm, which will result in more protein loss and low protein content in the cheese. From the above results, it can be seen that the whey precipitation height range of the cheese of Example 1-5 is 37-40mm, indicating that the method of the present invention can achieve automatic whey separation; the whey precipitation height of the comparative cheese is less than 26mm or greater than 40mm, indicating that in the cheese preparation process, protein content, enzymolysis temperature, enzymolysis time, enzyme ratio, strain type and its ratio and other process conditions are key parameters and links for achieving automatic cheese whey separation. Changing one of the experimental conditions and process parameters will result in whey being unable to precipitate, a low height or too high a height.

[0122] Test Example 2

[0123] This test example tests the protein content in cheese. The test adopts the Kjeldahl nitrogen determination method in GB 5009.5-2016 "National Food Safety Standard Determination of Food Protein" as the determination method. After the test, the protein content results in the cheese are shown in Table 2.

[0124] Table 2 Protein content in cheese of Examples 1-5 and Comparative Examples 1-18

[0125]

[0126]

[0127] The normal range of protein content of the cheese in this test example is: 6.0%-6.5%. From the above results, it can be seen that the protein content of the cheese in Examples 1-5 ranges from 6.1% to 6.4%, indicating that the method of the present invention can achieve automatic whey separation and the protein content of the cheese is retained; the protein content of the cheese in the comparative example is less than 5.9%, indicating that the protein content, enzymatic hydrolysis temperature, enzymatic hydrolysis time, enzyme ratio, bacterial strain type and its ratio and other process conditions in the cheese preparation process are the key parameters and links to achieve the automatic whey separation of this application. Changing one of the experimental conditions and process parameters will result in a low protein content in the cheese.

[0128] Test Example 3

[0129] This test example tests the molecular weight distribution of cheeses of different embodiments and comparative examples. The test method is: the cheese sample is centrifuged at 5000×g for 20 minutes, the supernatant is placed in a -80°C refrigerator for storage, and the molecular weight distribution in the milk base under different time conditions is determined by high performance size exclusion chromatography, wherein the chromatographic column is TSK gel G3000PWXL (300mm×7.8mm, 7μm), the mobile phase is water, acetonitrile and trifluoroacetic acid, and the volume ratio between the three is 55:45:0.1, and the setting parameters are: flow rate is 0.6mL / min, injection volume is 10μL, column temperature is 32°C, and UV detector wavelength is 220nm.

[0130] Comparative Example 5, Example 5, Example 1, and Comparative Example 6, the enzymatic hydrolysis time in the cheese was 10 min, 20 min, 30 min, and 40 min, respectively. The cheese after whey separation was as follows: Figure 2 As shown in Figure 2, the molecular weight distribution of cheese prepared by enzymatic hydrolysis followed by fermentation is as follows Figure 3 As shown in the figure, the molecular weight distribution range is divided into six segments: <0.3kDa, 0.3-0.5kDa, 0.5-1.0kDa, 1.0-3.0kDa, 3.0-5.0kDa and >5.0kDa. After enzymatic hydrolysis, the percentage of protein molecular weight less than 5.0kDa increased significantly. At 10min, 20min and 30min of hydrolysis, the relative percentage of molecular weight less than 5.0kDa was 74.56%, 78.79% and 82.25% respectively. The content of small molecular weight peptides less than 1.0kDa in the sample increased significantly. This part of small molecular peptides may be related to automatic whey removal. The above data show that after hydrolysis and fermentation, the original protein structure of milk protein releases a certain amount of peptides.

[0131] The molecular weight distribution data is combined with the whey precipitation height and protein content data for analysis, such as Figure 4 As shown, the whey percentage is obtained by filtering the cheese after whey separation and then calculating the whey weight; from the analysis in the figure, it can be seen that when the enzymatic hydrolysis time is less than 20 minutes, the whey percentage is only 8.3%, resulting in a low protein content in the cheese, and the cheese protein after concentration is only 3.9%, which cannot achieve the effect of automatic whey removal; when the enzymatic hydrolysis time is greater than 30 minutes, the whey precipitation height exceeds 40 mm, the whey percentage is too high, exceeding 60%, and the protein content in the whey is relatively high, exceeding 1.9%, indicating that more peptides are hydrolyzed from the cheese and enter the whey part, resulting in a loose cheese texture, which is easy to cause texture collapse.

[0132] Test Example 4

[0133] This test example uses LC-MS / MS to identify the hydrolysis of peptide segments in the automatic separation of whey from cheese in Example 1. The test uses an ultrafiltration device and a C18 chromatographic column to ultrafilter and desalt the whey. The mobile phase A is a 0.1% formic acid aqueous solution by volume, and the B liquid is a mixture of formic acid and acetonitrile (the volume ratio of formic acid, acetonitrile, and water is 0.1:84:16). The chromatographic column is first equilibrated with a 95% volume fraction of A liquid, and the separation process adopts gradient elution. When the elution time is 0 to 50 minutes, the linear gradient of B liquid is 4% to 50%, when the desorption time is 50 to 54 minutes, the linear gradient of B liquid is 50% to 100%, and when the desorption time is 54 to 60 minutes, the linear gradient of B liquid is 100%. After chromatographic separation, a mass spectrometer is used for 60 minutes of mass spectrometry analysis, using positive ion detection, and data collection is based on the acquisition of 10 fragment spectra after each full scan. The database searched was Uniprot (https: / / www.uni-prot.org / ), and the mass spectrometry files were processed using MaxQuant software (version 1.6.2.0).

[0134] Through LC-MS / MS analysis, it was found that there were 458 peptides containing more than 8 amino acids in whey, with a molecular mass distribution of 0.81-3.02KDa. With the increase of enzymatic hydrolysis time, the content of small molecular weight peptides less than 1.0kDa in the sample increased significantly, verifying the correlation between small molecule peptides and automatic whey removal. The enzyme cleavage sites are mainly concentrated in C14-G35, Q53-P68, E83-A98, and E126-F154 of β-lactoglobulin, which contain more hydrophilic amino acids, such as arginine, aspartic acid, threonine, and serine. By releasing this part of the peptides containing hydrophilic amino acids, the whey is automatically separated, and the amino acid part that is not released has more hydrophobic amino acids, forming the special texture of cheese.

[0135] For those skilled in the art, when understanding the solutions described in the specific embodiments of the present invention, they can refer to the conventional technical manuals in the field. At the same time, for the places where the above-mentioned terms appear, they can make appropriate understandings or adjustments for reference, and deduce the implementation of the same or similar technical solutions without paying any creative work.

[0136] The above embodiments describe only the basic principles, main features and / or advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and the invention content of the specification only describe the principles or specific cases of the present invention. Without departing from the essence of the innovative idea of ​​the present invention, the innovative scheme of the present invention may be subject to various changes and improvements, and these changes and improvements all fall within the scope of protection required by the present invention.

Claims

1. A method for preparing cheese with automatic whey separation, comprising: Enzymatic hydrolysis: add 0.003-0.01 parts of alkaline protease and 0.001-0.003 parts of rennet to 99-100 parts of milk, mix well, and perform enzymatic hydrolysis at a temperature of 48-55° C. for 15-35 minutes to obtain an enzymatic protein base material; Fermentation: inoculate a fermentation agent into the enzymatic protein base material, the fermentation agent includes 0.001-0.01 parts of strain C-1 and 0.001-0.005 parts of strain PRIME 800, stir evenly and then ferment.

2. The method for preparing cheese with automatic whey separation according to claim 1, characterized in that: The protein content in cow's milk is 3.5wt% to 3.8wt%.

3. The method for preparing cheese with automatic whey separation according to claim 1, characterized in that: The ratio of alkaline protease to chymosin added is 4-2.5:

1.

4. The method for preparing cheese with automatic whey separation according to claim 3, characterized in that: The ratio of alkaline protease to chymosin added was 3:

1.

5. The method for preparing cheese with automatic whey separation according to claim 1, characterized in that: The conditions for enzymatic hydrolysis are 50-55°C for 20-30 minutes.

6. The method for preparing cheese with automatic whey separation according to claim 1, characterized in that: The added strain C-1 is 0.002 to 0.005 parts, and the added strain PRIME 800 is 0.0015 to 0.0025 parts.

7. The method for preparing cheese with automatic whey separation according to claim 6, characterized in that: The ratio of the added strain C-1 and strain PRIME 800 is 3 to 1.5:

1.

8. The method for preparing cheese with automatic whey separation according to claim 1, characterized in that: Before the enzymatic protein base material is fermented, it is necessary to homogenize and sterilize, with the homogenization temperature being 65°C and the homogenization pressure being 200 bar; the sterilization is carried out by pasteurization method, with the sterilization temperature being 95°C and the sterilization time being 300s.

9. The method for preparing cheese with automatic whey separation according to any one of claims 1 to 8, characterized in that: After inoculating the starter, the enzymatic protein base is filled and then fermented.

10. A cheese with automatic whey separation, characterized in that: The cheese is prepared by the method for preparing whey automatic separation cheese according to any one of claims 1 to 9.

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