Low-temperature long-time preservation fresh cheese and preparation method thereof

Abstract

The invention relates to the technical field of cheese preparation, in particular to low-temperature long-preservation fresh cheese and a preparation method thereof.The preparation method comprises the steps that raw milk is pretreated, then cheese, whey protein powder and butter are sequentially added, and shearing, homogenizing and first pasteurization treatment are conducted; the preparation method comprises the following steps: preparing fresh cheese, adding a fermentation strain, stirring, carrying out curdling treatment and demulsification treatment to obtain fresh cheese, adding auxiliary materials subjected to shearing and cooling into the fresh cheese, carrying out shearing, second pasteurization, homogenization, cooling, third pasteurization and hot filling treatment, and carrying out multiple heat treatment processes to obtain the low-temperature and long-term preservation fresh cheese. The cheese is uniform in texture, smooth in taste and rich in cheese flavor, not only can provide excellent tissue state, color and taste, but also can prolong the shelf life to 180 days.

Description

Technical Field

[0001] The invention relates to the technical field of cheese preparation, and in particular to a low-temperature, long-lasting fresh cheese and a preparation method thereof. Background Art

[0002] Fresh cheese is unripened or only slightly ripened cheese that not only retains the original flavor and nutrients of milk, but also has a soft texture, light taste, and high moisture content. Currently, most fresh cheese products on the market are made using traditional European techniques, and most of these products cater to the taste preferences of foreign consumers. Although some products on the market have attempted to adjust to the preferences of domestic consumers, there are significant differences in nutrient retention, taste retention, and flavor. Some products even have poor water retention, severe whey precipitation, a rough taste, and poor flavor, which not only affect product quality but also the nutritional value of the cheese. Furthermore, due to its high moisture content and susceptibility to microbial contamination, fresh cheese also presents product instability issues, resulting in a short shelf life, which has been a problem for manufacturers and consumers. Although sterilization can effectively reduce the number of microorganisms, excessive sterilization may affect the taste, flavor, and nutritional content of the cheese.

[0003] Therefore, it is particularly important to develop a fresh cheese that can meet the flavor preferences of domestic consumers while maintaining a good taste. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a low-temperature, long-lasting fresh cheese and a preparation method thereof. Through multiple low-temperature pasteurization, heat treatment and filling combined with a unique preparation method, the product shelf life is extended while ensuring the nutritional content, and the product texture and flavor are improved.

[0005] A method for preparing low-temperature, long-lasting fresh cheese, comprising a pretreatment process and a fermentation process, and also comprising multiple heat treatment processes, wherein the multiple heat treatment processes include a first heat treatment process, a second heat treatment process, and a third heat treatment process;

[0006] The first heat treatment process is to heat the first material obtained in the pretreatment process, add raw materials in batches and mix them, and then perform the first pasteurization after shearing and homogenization to obtain the second material;

[0007] The second heat treatment process is to mix the third material obtained in the fermentation process with the treated auxiliary material to obtain the fourth material, perform a second pasteurization, and then perform homogenization and cooling treatment to obtain the fifth material;

[0008] The third heat treatment process is to perform a third pasteurization heat treatment on the fifth material, and then cool it down after filling to obtain low-temperature long-lasting fresh cheese.

[0009] Furthermore, the temperature of the first pasteurization treatment is 92-95°C, and the time is 300-310s; the temperature of the second pasteurization treatment is 83-87°C, and the time is 20-30s; the temperature of the third pasteurization treatment is 63-67°C, and the time is 20-30s.

[0010] Furthermore, the pretreatment process is to take raw milk and perform standardization treatment, homogenization treatment and pasteurization treatment in sequence, wherein the pressure of the homogenization treatment is 180-200 bar; the temperature of the pasteurization treatment is 80-85° C., and the time is 15-20 seconds.

[0011] Furthermore, the protein content of the raw cow's milk is ≥3.1%, and the fat content is ≥3.47%; the protein content of the second material is ≥4.2%, and the fat content is ≥6.5%; the protein content of the fourth material is ≥3.3%, and the fat content is ≥4.9%.

[0012] Furthermore, the process of adding raw materials and mixing them in batches during the first heat treatment process is as follows: heating the first material obtained in the pretreatment process to 82-85°C, cooling it to 55-60°C after adding cheese, and then adding white sugar, butter, starch, and whey protein powder and mixing; the shear speed during the first heat treatment process is 700-800rpm, and the time is 20min; the homogenization temperature during the first heat treatment process is 55-60°C, the first-level homogenization pressure is 50bar, and the second-level pressure is 180-200bar.

[0013] Furthermore, the auxiliary materials in the second heat treatment process include purified water, white sugar, and colloid, wherein the processing process of the auxiliary materials includes shearing treatment and cooling treatment, the shearing treatment time is 20-35 minutes, and the cooling treatment temperature is 55-60°C.

[0014] Furthermore, the stirring and mixing time during the second heat treatment process is 20 minutes, and the stirring speed is 700-800 rpm.

[0015] Furthermore, the homogenization temperature during the second heat treatment process is 55-60° C., the first homogenization pressure is 50 bar, and the second homogenization pressure is 180-200 bar.

[0016] Furthermore, the fermentation process is to add fermentation bacteria to the second material and stir, the fermentation bacteria is lactic acid bacteria, the inoculation temperature is 32-34° C., the stirring time is 20 min, and the stirring speed is 500 rpm.

[0017] Furthermore, the method further comprises a coagulation treatment and a demulsification treatment after fermentation, wherein the coagulation time of the coagulation treatment is 7-8 hours, and the pH value of the coagulation end point is 4.4-4.5; and the demulsification treatment time is 10 minutes.

[0018] Furthermore, the method for preparing the low-temperature long-lasting fresh cheese comprises the following steps:

[0019] (1) Pretreatment process: pretreating the raw milk raw material to obtain the first material;

[0020] (2) First heat treatment process: the first material obtained in step (1) is heated and then mixed with raw materials in batches, and then sheared, homogenized and pasteurized for the first time are performed in sequence to obtain the second material;

[0021] (3) Fermentation process: adding the fermentation bacteria to the second material obtained in step (2) and stirring, and then performing a coagulation process and a demulsification process to obtain a third material;

[0022] (4) Second heat treatment process: adding the third material obtained in step (3) to the auxiliary material after shearing and cooling, stirring and mixing to obtain the fourth material, performing a second pasteurization treatment, and then performing homogenization and cooling treatment to obtain the fifth material;

[0023] (5) The fifth material obtained in step (4) is subjected to a third pasteurization heat treatment and is filled to obtain low-temperature long-lasting fresh cheese.

[0024] The present invention also provides a low-temperature long-lasting fresh cheese, which is prepared by the above-mentioned preparation method.

[0025] The advantages of the present invention are:

[0026] The first pasteurization of the present invention can reduce the number of microorganisms in raw milk, the second pasteurization can further kill microorganisms that may be introduced after the addition of auxiliary materials, and the third pasteurization hot filling ensures the microbial safety of the final product while avoiding excessive sterilization that affects the taste and nutrition. Through the synergistic effect of multiple heat treatment processes and various production processes, and in combination with special raw materials and auxiliary materials, fresh cheese with good taste, good flavor and rich nutritional value and capable of being stored at low temperature for a long time is prepared. The microbial safety and long-term shelf life of the product are guaranteed while maintaining good taste and flavor, meeting the taste preferences of domestic consumers, and solving the problems in the prior art that fresh cheese is easily susceptible to microbial contamination, has a short shelf life, and is difficult to strike a balance between sterilization treatment and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a process flow chart for preparing low-temperature long-lasting fresh cheese. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] It should be noted that the various installation methods and technical terms mentioned in the present invention are technical terms that have long been clearly known in the relevant technical field and therefore will not be further explained. In addition, the same reference numerals are used for the same components, but this does not affect nor constitute an accurate understanding of the technical solution by those skilled in the art.

[0030] Example 1

[0031] This embodiment provides a low-temperature, long-lasting fresh cheese, the raw materials of which include raw milk, cheese, white sugar, butter, starch and whey protein powder, and the auxiliary materials include purified water (in compliance with the national standard GB6682-2008), white sugar and colloid.

[0032] like Figure 1 As shown, the preparation process of the low-temperature long-lasting fresh cheese includes the following steps:

[0033] The method for preparing the low-temperature, long-lasting fresh cheese comprises the following steps:

[0034] (1) Raw milk acceptance: The fresh raw milk purchased from the farm is tested and enters the milk warehouse after passing the test;

[0035] (2) Pretreatment process: The raw milk raw material (in this embodiment, whole raw milk, with a protein content of ≥3.2% and a fat content of ≥3.5%) that has passed the acceptance inspection in step (1) is subjected to standardization treatment, homogenized at a pressure of 180 bar, and then pasteurized at a temperature of 82°C to obtain the first material after 15 seconds;

[0036] (3) First heat treatment process: the first material (880‰ of raw milk) obtained in step (2) is heated to 82°C, 14‰ of cheese is added and then cooled to 55°C, 40‰ of white sugar, 50‰ of butter, 10‰ of starch and 6‰ of whey protein powder are added and mixed (this batch addition process is also a material processing process), after mixing, sheared at a speed of 700 rpm for 20 minutes, and then homogenized at a temperature of 55°C, a primary pressure of 50 bar and a secondary pressure of 180 bar, and then pasteurized for the first time at a temperature of 92°C. After sterilization for 300 seconds, a second material is obtained (in this embodiment, the protein content of the second material is not less than 4.2%, and the fat content is not less than 6.5%);

[0037] (4) Fermentation process: at an inoculation temperature of 32°C, the fermentation bacteria (the fermentation bacteria in this embodiment are lactic acid bacteria) are added to the second material obtained in step (3), stirred at a stirring speed of 500 rpm for 20 min, and then subjected to a coagulation treatment for 7 h. When the end point pH value of the coagulation reaches 4.4, the emulsion is broken, and the third material (fresh cheese) is obtained after 10 min of demulsification;

[0038] (5) Second heat treatment process: 770% of the third material (fresh cheese) obtained in step (4) is added to the auxiliary material (the auxiliary material in this embodiment is a material obtained by heating 184‰ of pure water to 82°C, adding 40‰ of white sugar and 6‰ of colloid, and the auxiliary material needs to be sheared for 20 minutes and then cooled to 55°C), and stirred and mixed at a stirring speed of 700 rpm for 20 minutes to obtain the fourth material (the protein content of the fourth material in this embodiment is not less than 3.3%, and the fat content is not less than 4.9%), and then subjected to a second pasteurization treatment at a temperature of 83°C for 20 seconds, and then homogenized at a primary pressure of 50 bar and a secondary pressure of 180 bar, and cooled to 55°C to obtain the fifth material;

[0039] (6) Third heat treatment process: The fifth material obtained in step (5) is subjected to a third pasteurization heat treatment at a temperature of 63°C, and is filled after sterilization for 20 seconds. The filled product is moved into a 2-8°C environment and cooled to 8°C for storage to obtain low-temperature long-lasting fresh cheese.

[0040] Example 2

[0041] The method for preparing low-temperature, long-lasting fresh cheese provided in this embodiment is the same as that in Example 1, except that the raw materials in this embodiment further include milk protein powder and casein powder.

[0042] In the pretreatment process of this embodiment, the homogenization temperature is 85° C. and the homogenization pressure is 200 bar; the pasteurization temperature is 85° C. and the time is 20 seconds.

[0043] In the first heat treatment process of this embodiment, the first material (880‰ raw milk) is heated to 85°C, 14‰ cheese is added, and then the temperature is lowered to 60°C. Then, 40‰ white sugar, 50‰ butter, 10‰ starch, 2‰ whey protein powder, 2‰ milk protein powder, and 2‰ casein powder are added and mixed. The shear speed after mixing is 800 rpm. The homogenization temperature is 60°C, the primary pressure is 50 bar, and the secondary pressure is 200 bar. The first pasteurization temperature is 95°C, and the sterilization time is 310 seconds.

[0044] In the fermentation process of this embodiment, the inoculation temperature is 34°C, the coagulation time is 8 hours, and the pH value at the coagulation end point is 4.5;

[0045] In the second heat treatment process of this embodiment, the auxiliary material is a material obtained by heating 184‰ pure water to 85°C and adding 40‰ white sugar and 6‰ colloid. The shear rate of the auxiliary material is 800 rpm, the time is 35 minutes, and the cooling temperature is 60°C. The second pasteurization temperature is 87°C, the sterilization time is 30 seconds, the homogenization temperature is 60°C, and the homogenization pressure is 200 bar.

[0046] In the third heat treatment process of this embodiment, the third pasteurization temperature is 67° C. and the sterilization time is 30 seconds.

[0047] Example 3

[0048] The method for preparing low-temperature, long-lasting fresh cheese provided in this embodiment is the same as that in Example 1, except that, in the third heat treatment process of this embodiment, the third pasteurization temperature is 70° C. and the sterilization time is 30 seconds.

[0049] Example 4

[0050] The method for preparing low-temperature, long-lasting fresh cheese provided in this embodiment is the same as that in Example 1, except that, in the third heat treatment process of this embodiment, the third pasteurization temperature is 63° C. and the sterilization time is 40 seconds.

[0051] Example 5

[0052] The method for preparing low-temperature, long-lasting fresh cheese provided in this embodiment is the same as that in Example 1, except that, in the third heat treatment process of this embodiment, the third pasteurization temperature is 60° C. and the sterilization time is 30 seconds.

[0053] Comparative Example 1

[0054] The preparation method of a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that, in this comparative example, the amount of starch added in the material-making process in the first heat treatment process is 5‰. The specific process is as follows: 885‰ of raw milk is heated to 82°C, 14‰ of cheese is added, the temperature is lowered to 55°C, 40‰ of white sugar, 50‰ of butter, 5‰ of starch and 6‰ of whey protein powder are added and mixed.

[0055] Comparative Example 2

[0056] The preparation method of a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that, in this comparative example, the amount of starch added in the material-making process in the first heat treatment process is 15‰. The specific process is as follows: 875‰ raw milk is heated to 82°C, 14‰ cheese is added, cooled to 55°C, 40‰ white sugar, 50‰ butter, 15‰ starch and 6‰ whey protein powder are added and mixed.

[0057] Comparative Example 3

[0058] The preparation method of a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that the protein powder used in the first heat treatment process of this comparative example is milk protein powder. The specific process is as follows: 880‰ raw milk is heated to 85°C, 14‰ cheese is added, the temperature is lowered to 60°C, 40‰ white sugar, 50‰ butter, 10‰ starch and 6‰ milk protein powder are added and mixed.

[0059] Comparative Example 4

[0060] The preparation method of a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that the protein powder used in the first heat treatment process of this comparative example is casein powder. The specific process is as follows: 880‰ raw milk is heated to 85°C, 14‰ cheese is added, the temperature is lowered to 60°C, 40‰ white sugar, 50‰ butter, 10‰ starch and 6‰ casein powder are added and mixed.

[0061] Comparative Example 5

[0062] The method for preparing a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that, in the third heat treatment process of this comparative example, the third pasteurization temperature is 63° C. and the sterilization time is 50 s.

[0063] Comparative Example 6

[0064] The method for preparing a low-temperature, long-lasting fresh cheese provided in this comparative example is the same as that in Example 1, except that, in the third heat treatment process of this comparative example, the third pasteurization temperature is 73° C. and the sterilization time is 30 s.

[0065] Test Example 1

[0066] In this test, low-temperature, long-lasting fresh cheeses prepared by the methods of Examples 1-5 and Comparative Examples 1-6 were evaluated after refrigeration for six months. Key evaluation criteria included texture (viscosity, smoothness, presence of whey separation, etc.), mouthfeel, flavor, and acidity. The testing process involved randomly selecting 30 individuals aged 25-45 with food-related work experience or current food professionals. Each group of fresh cheeses was subjected to sensory evaluation and scoring. Each product was rinsed with mineral water before the sensory evaluation. The sensory scoring criteria for fresh cheese are shown in Table 1, and the sensory scores for Examples 1-5 and Comparative Examples 1-6 are shown in Table 2.

[0067] Table 1 Fresh cheese sensory quality scoring criteria

[0068]

[0069] Table 2 Sensory scores of fresh cheese prepared in Examples and Comparative Examples

[0070]

[0071]

[0072] As shown in the evaluation results in Table 2, the fresh cheeses of Examples 1-5 exhibited varying textures, color, taste, and flavor. The ranking of these results was as follows: Example 1 (100 points) > Example 5 (93 points) > Example 2 (86 points) > Example 4 (85 points) > Example 3 (83 points). Example 1 was evaluated as having good viscosity, uniform texture, no whey precipitation after 6 months of low-temperature aging, a milky white color, a delicate taste, no particles, and a characteristic rich, fresh cheese aroma. It achieved a comprehensive score of 100 points, making it the optimal example of this application. The fresh cheeses prepared by the methods of Comparative Examples 1-6 had lower comprehensive scores, being inferior to the examples in texture, color, taste, and flavor. This suggests that the amount of raw materials added and the process parameters during the preparation process can affect the quality of the fresh cheese.

[0073] Comparing the results of Example 1 with Comparative Examples 1 and 2, the starch addition amount in Example 1 was 10‰, and the cheese had a uniform texture, no whey precipitation, a delicate taste, and a rich cheese aroma; while the starch addition amount in Comparative Example 1 was 5‰, the cheese had a thin texture, whey precipitation, and the starch addition amount in Comparative Example 2 was 15‰, the cheese had poor viscosity, and a rough taste, indicating that the amount of starch added would affect the viscosity of the cheese and the whey precipitation.

[0074] Comparing the results of Example 1, Example 2 and Comparative Example 3, Comparative Example 4, Example 1 uses whey protein powder, and Example 2 uses a compound of whey protein powder, milk protein powder and casein powder, and the taste is delicate; while Comparative Example 3 uses milk protein powder alone, and Comparative Example 4 uses casein powder alone, and the flavor scores are low, indicating that the type and compound use of protein powder will affect the flavor of cheese.

[0075] Comparing the results of Examples 3, 4, and 5 with Comparative Examples 5 and 6, the third pasteurization hot filling temperature of Example 3 was 70° C., and the taste was rough and grainy; the sterilization time of Example 4 was 40 seconds, and the taste was slightly grainy; the sterilization time of Comparative Example 5 was 50 seconds, and the taste was obviously grainy; the sterilization temperature of Comparative Example 6 was 73° C., and the taste was rough, indicating that the sterilization temperature and time will affect the delicate taste of cheese.

[0076] It can be seen from the above sensory evaluation results that Example 1 performs excellently in all indicators, while the comparative examples have varying degrees of quality degradation under different process parameters, further illustrating that changes in added components and process conditions will have a significant impact on the taste, texture, flavor and microbial stability of the product. Improper addition ratios or process parameters (such as insufficient starch, use of a single protein powder, and excessive sterilization time) will cause whey precipitation, a crumbly taste, a weak flavor, and even excessive microorganisms in the cheese, thereby reducing its overall effect. By optimizing the formula (such as the ratio of starch and protein powder) and pasteurization heat treatment process parameters (such as sterilization temperature and time), the organizational state, taste, and flavor of low-temperature, long-shelf-life fresh cheese can be significantly improved, and the shelf life can be extended to 180 days.

[0077] Test Example 2

[0078] In this test example, the low-temperature, long-shelf-life fresh cheeses prepared in the best example 1 and the preferred example 5, which ranked first and second in the sensory evaluation scores, were subjected to microbial testing. The cheeses were refrigerated at 2-8°C for 6 months, with samples taken once a month to measure their microbial content to determine their shelf life. The results are shown in Tables 3 and 4:

[0079] surface Microbiological test results of the low-temperature long-lasting fresh cheese prepared in Example 1 after refrigeration for 6 months

[0080]

[0081] As shown in Table 3, the low-temperature, long-lasting fresh cheese prepared by the preparation formula and process of Example 1 of the present invention can effectively inhibit the growth of microorganisms and maintain the acid-base balance of the product. The microbiological results can be stored for 6 months under refrigeration conditions of 2-8°C and meet national regulatory requirements.

[0082] Table 4 Microbial detection results of the low-temperature long-lasting fresh cheese prepared in Example 5 after refrigeration for 6 months

[0083]

[0084] As shown in Table 4, the low-temperature, long-shelf-life fresh cheese prepared by the method and process of Example 5 of the present invention has incomplete sterilization due to the low sterilization temperature. Even though the pH value can inhibit some microorganisms, it cannot prevent the reproduction of residual bacteria, resulting in the total colony count exceeding the standard after 5 months. After refrigeration at 2-8°C for 5 months, the total colony count is too numerous to be counted, and its shelf life is limited to 120 days.

[0085] A comprehensive review of Tables 1, 2, 3, and 4 confirms that the fresh cheese ultimately produced in Example 1 not only offers excellent texture, color, and taste, but also has an extended shelf life of 180 days. This further demonstrates that the present invention significantly improves the texture uniformity, mouthfeel, and flavor intensity of cheese by precisely controlling the ratios of added components (e.g., starch and protein powder) and standardizing process parameters (temperature / time for triple pasteurization). The stability of the low-temperature, long-lasting fresh cheese of the present invention is a synergistic effect of the "pasteurization temperature + time + formulation system." Deviations in any of these parameters can affect protein denaturation, microbial activity, or system stability, leading to deteriorated product quality and a shortened shelf life, making it difficult for the resulting fresh cheese to achieve the desired low-temperature, long-lasting shelf life.

[0086] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention may be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the foregoing description. It is intended that all variations that fall within the meaning and range of equivalents of the claims be embraced within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any minor modifications, equivalent replacements, and improvements made to the above embodiments based on the technical essence of the present invention shall be included in the scope of protection of the technical solution of the present invention.

Claims

1. A method for preparing low-temperature long-lasting fresh cheese, comprising a pretreatment process and a fermentation process, characterized in that: It also includes multiple heat treatment processes, wherein the multiple heat treatment processes include a first heat treatment process, a second heat treatment process, and a third heat treatment process; The first heat treatment process is to heat the first material obtained in the pretreatment process, add raw materials in batches and mix them, and then perform the first pasteurization after shearing and homogenization to obtain the second material; The second heat treatment process is to mix the third material obtained in the fermentation process with the treated auxiliary material to obtain the fourth material, perform a second pasteurization, and then perform homogenization and cooling treatment to obtain the fifth material; The third heat treatment process is to perform a third pasteurization heat treatment on the fifth material, and then cool it down after filling to obtain low-temperature long-lasting fresh cheese.

2. The preparation method according to claim 1, characterized in that The temperature of the first pasteurization treatment is 92-95° C., and the time is 300-310 seconds; the temperature of the second pasteurization treatment is 83-87° C., and the time is 20-30 seconds; the temperature of the third pasteurization treatment is 63-67° C., and the time is 20-30 seconds.

3. The preparation method according to claim 1, characterized in that The pretreatment process is to take raw milk and perform standardization, homogenization and pasteurization in sequence, wherein the pressure of the homogenization is 180-200 bar; the temperature of the pasteurization is 80-85° C. and the time is 15-20 seconds.

4. The preparation method according to claim 3, characterized in that The protein content of the raw cow's milk is ≥3.1%, and the fat content is ≥3.47%; the protein content of the second material is ≥4.2%, and the fat content is ≥6.5%; the protein content of the fourth material is ≥3.3%, and the fat content is ≥4.9%.

5. The preparation method according to claim 1, characterized in that The process of adding raw materials and mixing them in batches during the first heat treatment process is as follows: heating the first material obtained in the pretreatment process to 82-85°C, cooling it to 55-60°C after adding cheese, and then adding white sugar, butter, starch, and whey protein powder and mixing; the shear speed during the first heat treatment process is 700-800rpm, and the time is 20min; the homogenization temperature during the first heat treatment process is 55-60°C, the first-level homogenization pressure is 50bar, and the second-level pressure is 180-200bar.

6. The preparation method according to claim 1, characterized in that The auxiliary materials in the second heat treatment process include purified water, white sugar, and colloid, wherein the processing process of the auxiliary materials includes shearing treatment and cooling treatment, the shearing treatment time is 20-35 minutes, and the cooling treatment temperature is 55-60°C.

7. The preparation method according to claim 6, characterized in that The stirring and mixing time during the second heat treatment process is 20 minutes, and the stirring speed is 700-800 rpm; the homogenization temperature during the second heat treatment process is 55-60°C, the first homogenization pressure is 50 bar, and the second homogenization pressure is 180-200 bar.

8. The preparation method according to claim 1, characterized in that The fermentation process comprises adding fermentation bacteria to the second material and stirring, wherein the fermentation bacteria is lactic acid bacteria, the inoculation temperature is 32-34° C., the stirring time is 20 min, and the stirring speed is 500 rpm.

9. The preparation method according to claim 1, characterized in that The method further includes a milk coagulation process and a milk demulsification process after fermentation. The milk coagulation process has a milk coagulation time of 7-8 hours and a pH value at the milk coagulation end point of 4.4-4.

5. The milk demulsification process has a milk demulsification time of 10 minutes.

10. A low-temperature, long-lasting fresh cheese, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 9.

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