Texture adjustment and preparation method of acidic single cream

Abstract

The invention relates to the technical field of food, and particularly provides texture adjustment and a preparation method of acidic single cream. The texture adjusting method provided by the invention comprises the following steps: performing steam direct injection type sterilization or tubular ultra-high-temperature sterilization on the curd obtained after acidification under a certain condition and performing sterile homogenization under a specific condition. By adopting the texture adjusting method provided by the invention, in the process of preparing the acidic single cream, sterilization and sterile homogenization modes are optimized for acidified curds, the texture of the curds is adjusted under the conditions of no whey discharge process and no addition of a thickening agent and a stabilizing agent, and the acidic single cream with certain hardness, smearing property and whipping property is obtained. And the acidic single cream is good in texture.

Description

Technical Field

[0001] The invention relates to the technical field of food, and specifically provides a texture adjustment of sour cream and a preparation method thereof. Background Art

[0002] Acidified cream is widely used in the food industry, such as baking, cakes, cooking, and cakes, due to its mild creamy flavor, light sour taste, lack of bitterness, silky creamy texture, and certain spreadability.

[0003] The production process of sour cream includes the acidification process, and the acidification process includes fermentation acidification and exogenous acidification. Specifically, exogenous acidification refers to heating the cream to 80~95℃, adding a certain amount of organic acid such as tartaric acid, lactic acid or citric acid to acidify the cream, and then putting the resulting curd into a cloth bag to drain and discharge the whey to further obtain sour cream. Fermentation acidification refers to homogenizing and pasteurizing the standardized cream, adding a starter or rennet to make the cream reach a certain pH value for curdling, terminating the fermentation through heat treatment, and then putting the resulting curd into a cloth bag to discharge the whey to further obtain sour cream.

[0004] Whether it is the traditional production method of exogenous acidification or fermentation acidification, there is a whey discharge process, which generally takes 20 hours, which makes it difficult to achieve continuous production of acidified cream, and there are problems such as low product yield and long production time. In order to improve the production efficiency of acidified cream, with the maturity of membrane separation technology, it has been reported that the curd obtained after exogenous acidification or fermentation acidification can be drained of whey by centrifugation or membrane filtration to shorten the production time. However, this method still has the problems of intermittent production, low production yield (whey discharge rate 40%~80%), and cannot be produced continuously.

[0005] In order to improve production yield or even avoid whey discharge, realize continuous production, and ensure that the spreadability and texture of acidified cream are equivalent to those of acidified cream obtained by traditional production processes, some acidified cream products on the market use certain thickeners or stabilizers (such as locust bean gum, carrageenan, gellan gum, etc.) to enhance the texture (hardness, viscosity, etc.) and reduce whey precipitation to obtain a smooth and stable acidified cream. However, the ingredient list will contain thickeners or stabilizers, which does not meet the current product requirements for clean labels.

[0006] For example, the inventors proposed earlier that skimmed milk is concentrated to a protein concentrate with a protein concentration of 15-25%, and the protein raw material is mixed with cream, and then preheated at a certain temperature. When an acidity regulator is added after preheating for acidification, the obtained curd can be made to maintain good hardness, spreadability, large and stable foam expansion, reduced water separation rate, and no granularity without the need to discharge whey, and only through ultra-high temperature sterilization and homogenization. Moreover, the method has a high production yield. However, there are still certain limitations in mixing protein concentrate with cream as a protein raw material, which is specifically reflected in that the protein in sour cream plays a role in providing protein on the one hand, and on the other hand, it has a certain role in the formation of the hardness and other texture characteristics of sour cream. At present, about 82% of the sour cream products on the market for clean label sour cream products have a fat content greater than 35% and a protein content greater than 4%; when the protein content of the product is below 4%, the fat content needs to be increased to more than 40% to ensure that the texture (hardness, spreadability, viscosity, etc.) of the sour cream product reaches an ideal state. It can be seen that the formation mechanisms of the texture characteristics of curd in sour creams with different protein contents are different. In particular, the texture of sour creams with a protein content below 4% is more difficult to form. Therefore, a method for adjusting the texture of soured cream that is suitable for clean labels without draining whey or adding additional additives is urgently needed. Summary of the invention

[0007] As mentioned above, the prior art mainly considers obtaining sour cream with satisfactory hardness and spreadability by optimizing raw materials and thickeners, while little attention has been paid to how to adjust the texture of curd by adjusting the preparation process to obtain sour cream with good texture.

[0008] The present invention finds that the texture of the acidified curd can be regulated by designing and operating sterilization and homogenization parameters, thereby obtaining sour cream with different texture characteristics such as hardness. Specifically, the hardness of the sour cream is distributed in the range of 0.35N to 1.3N.

[0009] Therefore, in a first aspect of the present invention, there is provided a method for adjusting the texture of sour cream, comprising: mixing, pretreating and acidifying raw materials to obtain curd having a pH value of 5.0 to 6.5, wherein the curd is further subjected to high temperature sterilization and aseptic homogenization; The high temperature sterilization includes sterilizing the curd at an ultra-high temperature of 121-143° C. by direct steam injection for 2-10 seconds, or sterilizing the curd at an ultra-high temperature of 110-121° C. by tubular sterilization for 2-10 seconds; The aseptic homogenization temperature is 60-85° C., and the homogenization pressure is 20-40 MPa.

[0010] The texture characteristics of acidified cream products are mainly formed by the different effects of fat and protein. In the acidified cream system, fat mainly exists in the form of fat globules, and protein aggregates and wraps the fat globules to a certain extent. Therefore, optimizing the ratio of fat and protein can adjust the texture characteristics of acidified cream. Generally speaking, as the fat content increases, the hardness of the final product will be higher; as the fat content decreases, the hardness decreases and the spreadability becomes better. In the acidified cream system, although the sterilization process and the homogenization process are conventional process flows, the present invention has found in the study that under the sterilization process (equipment and parameters) and the homogenization process under specific conditions, the aggregation degree of protein and the degree of wrapping of fat globules can be adjusted to the optimal state, thereby achieving the texture optimization of acidified cream. The texture optimization method proposed by the present invention by optimizing the process conditions is different from the texture optimization method by optimizing the raw material ratio. The method proposed by the present invention is applicable to a wider range of raw materials and ratios for preparing clean label acidified cream without draining whey.

[0011] Preferably, according to the method for adjusting the texture of the sour cream provided by the present invention, the curd is sterilized by direct steam injection at ultra-high temperature of 121-140°C for 6-10s and then aseptically homogenized; or, the curd is sterilized by tubular ultra-high temperature of 110-121°C for 6-10s and then aseptically homogenized.

[0012] The adjustment of curd texture in the present invention depends on the coordination of sterilization equipment parameters and aseptic homogenization parameters. Preferably, in the texture adjustment method of sour cream provided by the present invention, the aseptic homogenization temperature is 75-85° C. and the homogenization pressure is 20-40 MPa.

[0013] As mentioned above, for low-protein sour cream with a protein content of less than 4%, it is more difficult to adjust its texture due to its low protein content. In experiments, it is found that the texture adjustment method of the present invention is not only applicable to the texture adjustment of high-protein sour cream, but also to the texture adjustment of low-protein sour cream. When adjusting the texture of low-protein curd, there is no need to drain whey during the production process.

[0014] In other words, the present invention has found that in the process of preparing sour cream with a low protein content, the design and combination of a specific sterilization method and an aseptic homogenization method for the acidified curd can control and regulate the hardness, spreadability and other textures of the finished sour cream without draining whey and adding additional additives.

[0015] Therefore, by adopting the texture adjustment method of the present invention, when using raw materials with a lower protein content to prepare sour cream, there is no need to drain whey, and the textures such as hardness and spreadability of conventional sour cream can still be achieved, and there is no need to add a thickener. The obtained sour cream meets the clean label standard.

[0016] Preferably, according to the method for adjusting the texture of the sour cream provided by the present invention, the fat content of the curd is 35-45% by mass, and the protein content is 2-7% by mass; further preferably, the fat content of the curd is 35-45% by mass, and the protein content is 2-4% by mass; more preferably, the fat content of the curd is 35-40%, and the protein content is 2-4%.

[0017] In the present invention, when the protein content in the curd is any value of 2-7%, and the fat content in the curd is 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44% or 45%, the texture adjustment method of the present invention can be adopted to achieve the hardness, spreadability and other textures of conventional sour cream without draining whey, and no thickener needs to be added, and the obtained sour cream meets the clean label standard.

[0018] In a second aspect, the present invention further provides a method for preparing sour cream, comprising: preparing the sour cream using the method for adjusting the texture of sour cream.

[0019] Preferably, according to the method for preparing sour cream provided by the present invention, the acidification comprises: exogenous acidification and fermentation acidification.

[0020] The exogenous acidification includes obtaining curd by adding organic acid.

[0021] The fermentation and acidification comprises: obtaining curd by inoculating Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris.

[0022] Preferably, the method for preparing sour cream provided by the present invention further comprises: adding a protein concentrate to the cream and then acidifying it. As described above, the texture adjustment method provided by the present invention can adjust the texture of curd of any formula, so when using the above texture adjustment method to prepare sour cream, a protein concentrate can be added to the cream and then acidified to obtain a sour cream with a specific protein content, hardness, and spreadability that meets the requirements.

[0023] Preferably, the method for preparing sour cream provided by the present invention comprises: mixing cream and protein raw materials, preheating, exogenous acidification, high temperature sterilization, aseptic homogenization, filling and maturation.

[0024] Alternatively, preferably, the method for preparing sour cream according to the present invention comprises: mixing cream and protein raw materials, sterilizing, fermenting and acidifying, demulsifying, preheating, high-temperature sterilizing, aseptically homogenizing, filling and maturing.

[0025] In the above method, when the cream and the protein raw material are mixed, the process of adjusting the protein and fat content (such as heating, centrifugation, adding protein concentrate) so that the protein and fat content of the mixed cream reaches the set content can also be called standardization.

[0026] In a third aspect, the present invention provides a sour cream prepared by the above preparation method.

[0027] The sour cream provided by the invention has a fat content of 35-45% and a protein content of 2-7%.

[0028] The beneficial effects of the present invention are: The invention omits the whey discharge process by optimizing the sterilization equipment, sterilization conditions and aseptic homogenization conditions of the curd. Moreover, under the optimized process conditions, the texture of the curd with various protein contents can be adjusted, so as to obtain the sour cream with good textures such as hardness and whipping property.

[0029] When the sour cream is prepared by the texture adjustment method, the whole production process does not need to drain whey, and the production yield is substantially 100%. Therefore, the sour cream of the present invention has a short preparation time and can be produced continuously. The obtained sour cream has the same hardness, spreadability and viscosity as the traditional acidified cream. In addition, the sour cream obtained by the present invention has a low water separation rate, no granularity, and a clean ingredient list. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a laser confocal image of the sour cream prepared when the pH value of the curd is 4.5.

[0031] Figure 2 This is a laser confocal image of the sour cream prepared when the pH value of the curd is 5.5.

[0032] Figure 3 This is a laser confocal image of the sour cream prepared when the pH value of the curd is 6.5. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The present invention provides the following test indicators and methods for testing products: (1) Microstructure of fat protein: The observation method is laser confocal detection. The specific method includes: using biological dye labeling method and combining laser confocal microscopy to observe the microstructural changes of fat globule aggregation in gel samples of different crystalline fats, the distribution and aggregation state of fat protein. The specific conditions are: (1) Co-staining the protein and fat in the fast green and Nile red samples. For example: add 40μL of 1mg / mL fast green solution and 10μL of 1mg / mL Nile red ethanol solution to 4mL sample, respectively, and stain in the dark for more than 2h after mixing. Take 10μL of the stained sample and drop it on a clean slide to make it evenly distributed on the slide surface. (2) Laser confocal detection: The laser confocal conditions are Ar / Kr laser source, 100x objective lens, fluorescence mode, and the excitation light source wavelengths are 633nm and 560nm respectively. Among them, the fat in sour cream is dyed red and the protein is dyed green. The pictures obtained from the test reflect the size and spatial state of fat and protein under different treatment conditions.

[0035] (2) Hardness, spreadability and viscosity: After the samples were stored in a refrigerator at 4°C for 12 h, the hardness, spreadability and viscosity of the samples were measured using a TA-XTPlus physical property tester. Speed ​​before test: 8.0 mm / s; speed during test: 3 mm / s; speed after test: 10 mm / s; test distance: 13 mm; test time: 5 s; probe model: cylindrical probe (diameter 35 mm), and all samples were tested 3 times.

[0036] (3) Whey precipitation amount: Take 30 g of sour cream sample and place it at room temperature for 1 hour. Centrifuge it at 20℃ and 3000 r / min for 30 min. Collect the whey at the bottom layer and express it as the mass of whey precipitated per 100 g of sample (%).

[0037] (4) Whipping properties of acidified cream: Mix acidified cream and whipping cream in a ratio of 1:1, whip at high speed for 60 seconds, and observe the degree of expansion. The score is 0 to 10, with the higher the score, the greater the degree of expansion.

[0038] (5) Product yield = (finished product quantity / raw material quantity) × 100%; the raw material quantity is the sum of all raw materials used: including cream, various protein raw materials or protein liquid, etc.

[0039] (6) Flavor and taste: The tasters are professionally trained personnel, and the number of tasters is not less than 10. Take 20g of the sample and place it in a tasting cup with a lid. The taster uses a small spoon to weigh an appropriate amount of sour cream, observe its color, surface state and fluidity; smell the odor; finally put it in the mouth and taste its fineness, granularity, freshness, and milky aroma. The evaluation criteria are shown in Table 1.

[0040] Table 1

[0041] Example 1 Preparation of low-protein sour cream by exogenous acidification This embodiment provides a method for preparing sour cream by exogenous acidification, the steps are as follows: (1) Using raw milk as raw material, a cream separator was used to produce cream with a fat content of 50% and skimmed milk at a temperature of 50-70°C and a rotation speed of 7000 rpm.

[0042] Among them, the fat content in skimmed milk is less than 0.2%.

[0043] (2) Skim milk at 45±2℃ was treated with a 10 kDa rolled ultrafiltration membrane with a concentration ratio of 6 to produce a high-protein concentrate with a protein concentration of 17%.

[0044] (3) The cream is mixed with the protein concentrate. The fat content of the mixed mixture is 45% and the protein content is 3%.

[0045] (4) Preheating: Preheat the mixed cream to 75±2℃.

[0046] (5) Acidification: Add a 10% citric acid aqueous solution to the mixture by spraying, and stir the mixture at 50 rpm to obtain curd. The pH value of the curd reaches 5.5.

[0047] (6) The acidified curd is sterilized by direct steam injection at ultra-high temperature at 140°C for 8 seconds.

[0048] (7) Aseptic homogenization: The curd sterilized in step (6) is cooled to 75°C and aseptically homogenized at a homogenization condition of 30 MPa.

[0049] (8) Aseptic filling: Cool the homogenized curd to 45°C for aseptic filling.

[0050] (9) Ripening: The filled curd is matured at 2-8°C for 12 hours and then refrigerated to obtain sour cream.

[0051] The sour cream obtained in this embodiment has a fat content of 45%, a protein content of 3%, and a pH value of 5.5.

[0052] Example 2 Preparation of low-protein sour cream by exogenous acidification This embodiment provides a method for preparing sour cream by exogenous acidification. The difference between this embodiment and embodiment 1 is that: Step (6) of this embodiment: the acidified curd is sterilized by ultra-high temperature sterilization in a tube-type system at 121°C for 8s.

[0053] (7) Aseptic homogenization: The curd sterilized in step (6) is cooled to 75°C and aseptically homogenized at a homogenization condition of 20 MPa.

[0054] The resulting sour cream had a fat content of 45%, a protein content of 3% and a pH of 5.5.

[0055] Example 3 Preparation of low-protein sour cream by fermentation and acidification This embodiment provides a method for preparing sour cream by fermentation and acidification, the steps are as follows: (1) Using raw milk as raw material, a cream separator is used at a temperature of 50-70°C and a rotation speed of 7000 rpm to produce cream with a fat content of 50% and skimmed milk, wherein the fat content of the skimmed milk is less than 0.2%.

[0056] (2) Skim milk at 45±2℃ was treated with a 10 kDa rolled ultrafiltration membrane with a concentration ratio of 6 to produce a high-protein concentrate with a protein concentration of 17%.

[0057] (3) Standardization: The cream is mixed with the protein concentrate to obtain a mixture having a fat content of 45% and a protein content of 2%.

[0058] (4) The mixture obtained in step (3) is pasteurized (95°C, 60s).

[0059] (5) The sterilized cream was cooled to 28°C, inoculated with a certain amount of Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris, and fermented for 15 h until the pH value reached 5.5.

[0060] (6) Stir to break the emulsion and raise the temperature to 75°C.

[0061] (7) The acidified material is sterilized by direct steam injection at ultra-high temperature at 140°C for 8 seconds.

[0062] (8) Aseptic homogenization: The sterilized curd is cooled to 75°C and aseptically homogenized at a homogenization condition of 40 MPa.

[0063] (9) Aseptic filling: Cool the homogenized curd to 45°C for aseptic filling.

[0064] (10) Maturation: The filled curd is matured at 2-8°C for 12 hours and then refrigerated.

[0065] The resulting sour cream had a fat content of 45%, a protein content of 2% and a pH of 5.5.

[0066] Example 4 Preparation of low-protein sour cream by fermentation and acidification This embodiment provides a method for preparing sour cream by fermentation and acidification. The difference between this embodiment and embodiment 3 is that: Step (7) of this embodiment: the acidified material is sterilized by ultra-high temperature sterilization in a tube-in-tube manner: 121°C, 8s.

[0067] (8) Aseptic homogenization: The sterilized curd is cooled to 75°C and aseptically homogenized at a homogenization condition of 20 MPa.

[0068] The resulting sour cream had a fat content of 45%, a protein content of 2% and a pH of 5.5.

[0069] Example 5 Preparation of high protein content sour cream by exogenous acidification This embodiment provides a method for preparing exogenous acidified cream, the steps are as follows: (1) Using raw milk as raw material, a cream separator is used at a temperature of 50-70°C and a rotation speed of 7000 rpm to produce cream with a fat content of 50% and skimmed milk, wherein the fat content of the skimmed milk is less than 0.2%.

[0070] (2) Skim milk at 45±2℃ was treated with a 10 kDa rolled ultrafiltration membrane with a concentration ratio of 6 to produce a high-protein concentrate with a protein concentration of 17%.

[0071] (3) The light cream is mixed with the ultrafiltered high-protein concentrate so that the fat content of the mixed light cream is 37% and the protein content is 5%.

[0072] (4) Preheating: Preheat the mixed cream to 75±2℃.

[0073] (5) Acidification: Add a 10% citric acid aqueous solution to the mixture by spraying, and stir the mixture at 50 rpm to obtain curd. The pH value of the curd reaches 5.5.

[0074] (6) The acidified material is sterilized by direct steam injection at ultra-high temperature at 140°C for 8 seconds.

[0075] (7) Aseptic homogenization: The curd sterilized in step (6) is cooled to 75°C and aseptically homogenized at a homogenization condition of 30 MPa.

[0076] (8) Aseptic filling: Cool the homogenized curd to 45°C for aseptic filling.

[0077] (9) Ripening: The filled curd is matured at 2-8°C for 12 hours and then refrigerated to obtain the sour cream.

[0078] The resulting sour cream had a fat content of 37%, a protein content of 5% and a pH of 5.5.

[0079] Example 6 Preparation of high protein sour cream by fermentation and acidification This embodiment provides a method for preparing sour cream by fermentation and acidification. The difference from Embodiment 5 is that in this embodiment, cream with a fat content of 37% and a protein content of 5% is pasteurized (95° C., 60 s).

[0080] The sterilized cream was cooled to 28°C, inoculated with a certain amount of Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris, and fermented for 15 hours until the pH value reached 5.5. The cream was stirred to break the emulsion and heated to 75°C to prepare the acidified material.

[0081] The other steps are the same as those in Example 5. The sour cream obtained in this example has a fat content of 37%, a protein content of 5%, and a pH value of 5.5.

[0082] Example 7 Different degrees of acidification The method for preparing sour cream used in this example is the same as that in Example 1. This example explores the pH values ​​of the curd during acidification in step (5) to reach 4.5, 5.5, and 6.5, respectively, wherein the pH value of the curd is 5.5, which is Example 1.

[0083] Laser confocal microscopy of fat and protein distribution of sour cream under different curd pH conditions Figure 1-3 , red represents fat particles; green represents protein particles. Figure 1 In the experiment, fat globules were of different sizes and had large diameter differences, and proteins aggregated; Figure 2 The number of medium and large fat globules decreased, protein aggregation decreased, and some proteins were wrapped on the surface of fat globules; Figure 3 The size of fat globules tends to be consistent, and more protein wraps around the surface of fat globules.

[0084] Through laser confocal analysis of sour cream under different pH conditions, it can be seen that under pH values ​​of 5.5 and 6.5, whey protein aggregation is reduced, the size of fat globules tends to be consistent, and whey protein is wrapped on the surface of fat globules, reducing the tendency of fat globules to aggregate and stabilizing the system. At the same time, the texture test results show that under pH value of 4.5, the hardness, spreadability and viscosity of sour cream are greatly reduced.

[0085] Comparative Example 1 The difference between this comparative example and Example 2 is that in this comparative example, step (6): the acidified curd is sterilized under different conditions using a tubular ultra-high temperature sterilization method.

[0086] In the treatment group 1 (Comparative Example 1-1) of this comparative example, the shell-and-tube ultrahigh temperature sterilization conditions used were 137° C., 4 s; in the treatment group 2 (Comparative Example 1-2), the shell-and-tube ultrahigh temperature sterilization conditions used were 137° C., 6 s.

[0087] The experiment failed, the material was not formed, and the texture requirements were not met.

[0088] Comparative Example 2 The difference between this comparative example and Example 1 is that in step (7) of this comparative example, the curd sterilized in step (6) is cooled to 75° C. and the aseptic homogenization condition is 14 MPa.

[0089] The experiment failed, the material was not formed, and the texture requirements were not met.

[0090] Comparative Example 3 The difference between this comparative example and Example 2 is that in step (7) of this comparative example, the curd sterilized in step (6) is cooled to 75° C. and the aseptic homogenization condition is 14 MPa.

[0091] The experiment failed, the material was not formed, and the texture requirements were not met.

[0092] Comparative Example 4 The difference between this comparative example and Example 1 is that the time used for sterilization in step (6) in this comparative example is 1.5 s.

[0093] The experiment failed, the material did not take shape, and the product hygiene conditions did not meet the standards.

[0094] Experimental Example 1 This experimental example tests the hardness, spreadability, viscosity, swelling degree, whey precipitation amount and yield of the product of the embodiment. The results are shown in Table 2 below.

[0095] Table 2

[0096] Experimental Example 2 This experimental example tests the flavor and taste of the product of the embodiment, wherein, since comparative examples 1, 2, 3 and 4 cannot meet the molding requirements and comparative example 4 cannot meet the sanitary conditions, the flavor and taste evaluation is not performed. The results are shown in Table 3 below.

[0097] Table 3

[0098] It can be seen from the test results of the above embodiments and comparative examples that: Through the setting of specific sterilization equipment and specific parameters, the texture of sour cream products with different protein contents can reach the same texture as traditional sour cream, and even the hardness and spreadability can be further improved. At the same time, the process of protein supplementation can be avoided, and the cost of ingredients can be reduced. The texture characteristics are equal to or better than those of traditional sour cream products without discharging whey and improving production yield.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for adjusting the texture of sour cream, characterized in that: include: The raw materials are mixed, pretreated, and acidified to obtain curd having a pH value of 5.0 to 6.5, and the curd is further sterilized at high temperature and aseptically homogenized; The curd has a fat content of 35-45% and a protein content of 2-7% by mass; The high temperature sterilization includes sterilizing the curd at an ultra-high temperature of 121-143° C. by direct steam injection for 2-10 seconds, or sterilizing the curd at an ultra-high temperature of 110-121° C. by tubular sterilization for 2-10 seconds; The aseptic homogenization temperature is 60-85° C., and the homogenization pressure is 20-40 MPa.

2. The method for adjusting the texture of sour cream according to claim 1, characterized in that: The curd is sterilized by direct steam injection at ultra-high temperature of 121-140° C. for 6-10 seconds and then aseptically homogenized; Alternatively, the curd is sterilized at ultra-high temperature of 110-121° C. for 6-10 seconds and then aseptically homogenized.

3. The method for adjusting the texture of sour cream according to claim 1, characterized in that: The aseptic homogenization temperature is 75-85° C., and the homogenization pressure is 20-40 MPa.

4. The method for adjusting the texture of sour cream according to any one of claims 1 to 3, characterized in that: The curd has a fat content of 35-45% and a protein content of 2-4% by mass.

5. A method for preparing sour cream, characterized in that: include: The sour cream is prepared using the method for adjusting the texture of sour cream according to any one of claims 1 to 4.

6. The method for preparing sour cream according to claim 5, characterized in that: The acidification includes: exogenous acidification and fermentation acidification; The exogenous acidification includes: obtaining curd by adding organic acid; The fermentation and acidification comprises: obtaining curd by inoculating Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris.

7. The method for preparing sour cream according to claim 6, characterized in that: Also includes: The acidification is carried out after the addition of the protein concentrate to the cream.

8. The method for preparing sour cream according to claim 6 or 7, characterized in that: include: Mix, pre-treat, acidify, pasteurize, homogenize and fill cream and protein ingredients.

9. A sour cream, characterized in that Prepared by the preparation method according to any one of claims 6 to 8.

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