Milk skin yoghourt and preparation method thereof

Abstract

The invention provides milk skin yoghurt and a preparation method thereof, the milk skin yoghurt has an obvious layered structure, the upper layer is milk skin, and the lower layer is yoghurt; and the milk skin is golden yellow. According to the technical scheme, on the basis of homogenizing treatment, integrated forming can be achieved, the milk skin yoghourt which has milk skin, is obviously layered and stable in structure is provided, and the milk skin yoghourt is novel and attractive in appearance structure, silky and smooth in texture, fragrant and thick in milk fat and very suitable for being used as net red yoghourt for street drinks and catering.

Description

Technical Field

[0001] The invention relates to the technical field of fermented milk, in particular to a milk skin yogurt and a preparation method thereof. Background Art

[0002] Dairy products are recognized and accepted by more and more consumers due to their rich nutrition and mellow taste, especially fermented dairy products, which are loved by more and more consumers because they can produce more substances beneficial to human health and have a sweet and sour taste during the fermentation process.

[0003] Currently, the consumption of dairy products is no longer limited to pre-packaged forms. With the popularity of street drinks, milk / yogurt has become the new favorite of street drinks and tea drinks. In addition to the mix and match of dairy products and other beverage elements, more and more yogurt products with Internet celebrity flavors and novel states are loved by consumers. How to provide a yogurt product that can meet consumers' requirements for novel states, rich structures, delicate taste, and rich milk flavor is a challenge faced by dairy product R&D personnel. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a milk skin yogurt and a preparation method thereof, so as to solve the problems in the prior art.

[0005] To achieve the above objectives and other related objectives, the present invention is achieved through the following technical solutions.

[0006] A first aspect of the present invention provides a milk skin yogurt, wherein the milk skin yogurt has a distinct layered structure, wherein the upper layer is milk skin and the lower layer is yogurt; the milk skin is golden yellow.

[0007] Preferably, based on the total mass of the raw materials of the milk yogurt, the milk yogurt includes the following raw materials: 2-3wt% butter, 3-5wt% light cream, 0.1-0.2wt% egg yolk powder, 0.1-1wt% milk protein powder, 6-8wt% sweetener, 0.05-0.4wt% stabilizer, 0.002-0.005wt% starter, and the balance is raw milk.

[0008] For example, the content of butter can be 2-2.5wt%, 2.5-3wt%; the content of light cream can be 3-4wt%, 4-5wt%; the content of milk protein powder can be 0.1-0.7wt%, 0.1-0.5wt%, 0.7-1wt%; the content of sweetener can be 6wt%, 7wt%, 8wt%; the content of stabilizer can be 0.05-0.3wt%, 0.2-0.4wt%, 0.2-0.3wt%; the content of leavening agent can be 0.002wt%, 0.003wt%, 0.004wt%, 0.005wt%.

[0009] Preferably, the thickness of the milk skin is greater than 1 mm.

[0010] Preferably, the acidity of the milk yogurt is 70-75°T, such as 70°T, 71°T, 72°T, 73°T, 74°T, or 75°T.

[0011] Preferably, the stabilizer is selected from one or a combination of pectin, gelatin and diacetyl tartaric acid mono- and diglycerides.

[0012] More preferably, the stabilizer is selected from a compound of pectin and gelatin, and the mass ratio of pectin to gelatin is (1-2): (1-4). For example, the mass ratio of pectin to gelatin can be (1-2): 1, (1-2): 4, 1: (1-4), 2: (1-4). The content of the stabilizer is not set arbitrarily. If no stabilizer is added or the stabilizer content is too low, the texture of the coagulated yogurt cannot be firm and smooth, and the water retention is poor, and the whey is easy to precipitate; if the stabilizer content is too high, the viscosity of the product raw material is too high, which affects the flow and the uniform mixing of the raw materials. The product tastes poor after fermentation, which affects swallowing and is not popular with consumers.

[0013] Preferably, the fat content of the butter is above 95wt%. The selection of the type and content of the butter is not random. Only within the range of 2-3wt% can the final product have a smooth and non-sticky taste while ensuring that a certain thickness of milk skin is formed on the top layer. The selection of butter with a high fat content is conducive to the formation of the top layer of milk skin, which effectively increases the fat content of the product, thereby allowing the milk skin to be formed while retaining the homogenization means, and the milk skin has a certain thickness; at the same time, the color of the butter makes the milk skin golden yellow, which has a significant color difference from the solidified part of the lower layer, and the shape is novel and easy to be loved by consumers.

[0014] Preferably, the fat content of the cream is 35-40 wt%.

[0015] Preferably, the cream is separated from whole milk.

[0016] The selection of the type of the light cream and the addition amount of 3 to 5 wt % are also specific. Within this range, the final product can have a richer cream flavor, and the light cream with a higher fat content can further facilitate the formation of the top layer of milk skin. Specifically, by using a specific type and amount of light cream, not only can the fat content in the raw materials be supplemented, further promoting the formation of the top layer of milk skin, but also the cream aroma that is significantly better than butter can be provided, thereby making the final product rich in milk flavor.

[0017] Preferably, the protein content of the milk protein powder is above 75 wt%.

[0018] The milk protein powder described in this application refers to a protein powder extracted from milk by conventional techniques such as low-temperature nanofiltration membrane separation technology, and the milk protein powder contains all the proteins in milk, namely, about 80% casein and 20% whey protein. This application does not specifically limit the brand and type of the milk protein powder. As long as it is a milk protein powder sold on the market that can meet the whole milk protein content of more than 75wt%.

[0019] The addition of the milk protein powder is conducive to forming a more compact texture of the final product, thereby providing stability and water retention of the final product, while also making the mouth feel full.

[0020] Preferably, the sweetener is selected from one or more of white granulated sugar, fructose syrup, maltose, erythritol, and stevioside. More preferably, the sweetener is selected from white granulated sugar.

[0021] Preferably, the fermentation agent is selected from one or more of Lactobacillus delbrueckii subsp.bulgaricus and Streptococcus salivarius subsp.thermophilus, wherein the Latin names of Lactobacillus delbrueckii subsp.bulgaricus and Streptococcus salivarius subsp.thermophilus are respectively.

[0022] A second aspect of the present invention provides a method for preparing the milk skin yogurt as described above, which specifically comprises the following steps:

[0023] 1) The milk protein powder, sweetener and stabilizer are mixed evenly, then added into the first raw milk, stirred and homogenized while keeping warm.

[0024] 2) The homogenized material in step 1) is heated to a second temperature, and then the second raw milk, egg yolk powder, cream and butter are added, stirred until completely dissolved, sterilized and cooled.

[0025] 3) adding a leavening agent to the cooled material in step 2), stirring the material evenly, canning the material, and fermenting the material at a constant temperature. After the fermentation is completed, cooling the material to obtain the milk yogurt.

[0026] Preferably, the first raw cow's milk refers to 1 / 3 to 2 / 3 of the total raw cow's milk, more preferably 1 / 3 of the total raw cow's milk.

[0027] Preferably, in step 1), the temperature of the first raw milk is 50-55°C, such as 50°C, 51°C, 52°C, 53°C, 54°C, or 55°C.

[0028] Preferably, the second raw milk refers to 1 / 3 to 2 / 3 of the total raw milk, more preferably 2 / 3 of the total raw milk.

[0029] In the present application, the raw materials are creatively added in batches in combination with a technical means of homogenizing specific raw materials, thereby ensuring that the powder and stabilizer in the raw materials can be fully dissolved and mixed evenly to ensure the stability and water retention of the final product, while also avoiding excessive stirring and crushing of the fat source in the raw materials, so that an integrated milk skin yogurt with obvious stratification and thick milk skin can be provided in the end.

[0030] Preferably, the time of the heat preservation and stirring is 10 to 15 minutes. For example, the time of the heat preservation and stirring can be 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, or 15 minutes.

[0031] Preferably, the homogenization temperature is 60-65°C, such as 60°C, 61°C, 62°C, 63°C, 64°C, or 65°C.

[0032] Preferably, the homogenization pressure is 80-100 bar. For example, the pressure may be 80-90 bar, 90-100 bar. The homogenization process is very important. In the production process, homogenization is conducive to the full dispersion and dissolution of the raw materials, especially the full dissolution and dispersion of the powder and stabilizer. If homogenization is not used, the final product will be rough, uneven in texture, poor in stability and water retention, and the top layer will easily precipitate water when placed during the shelf life.

[0033] Preferably, the second temperature is 75-85°C, such as 75-80°C, 80-85°C.

[0034] Preferably, the sterilization temperature is 93-97°C, and the sterilization time is 5-7 minutes. For example, the sterilization temperature is 93°C, 94°C, 95°C, 96°C, 97°C, and the sterilization time is 5 minutes, 6 minutes, or 7 minutes.

[0035] Preferably, the cooling is to fermentation temperature.

[0036] Preferably, the constant temperature fermentation temperature is 40-43°C, and the fermentation is completed when the temperature reaches 70-75°F.

[0037] Preferably, the temperature is lowered to 4-6°C after fermentation is completed.

[0038] The third aspect of the present invention provides a milk skin yogurt, which is prepared by the preparation method as described above.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention creatively provides a coagulated yogurt with obvious stratification and a golden milk skin on the top layer. The applicant selects specific raw materials and combines specific process methods to achieve perfect stratification of fat in the product, so that it can solidify on the top layer of yogurt to form a milk skin, and the thickness of the milk skin is greater than 1mm. The milk skin yogurt provided by the present invention has a novel and eye-catching appearance structure, a silky texture, and rich cream, which is very suitable for street drinking and catering to create Internet celebrity yogurt. DETAILED DESCRIPTION

[0041] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0042] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are intended to describe specific embodiments, rather than to limit the scope of protection of the present invention. The test methods in the following examples without specifying specific conditions are generally carried out under conventional conditions or under conditions recommended by the manufacturers.

[0043] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0044] The formation of milk skin is due to the fat in the raw material expanding after heating, floating to the surface and condensing. In the prior art, when preparing yogurt products, homogenization is usually performed to ensure the stable water retention of the product and prevent the precipitation of water. However, at the same time, homogenization will break the fat globules in the raw material into smaller particles and evenly distribute them in the milk product. Therefore, the homogenization operation will also prevent the fat from floating and the formation of milk skin.

[0045] The technical solution of the present invention, on the basis of homogenization treatment, can also be integrated to provide a milk skin yogurt with obvious stratification and stable structure. After a lot of exploratory experiments, the applicant provides a milk skin yogurt and a preparation method thereof. This application selects specific raw materials and combines specific process methods to achieve perfect stratification of fat in the product while ensuring the stability of the product system, so that it can solidify on the top layer of yogurt to form milk skin, and the thickness of the milk skin is greater than 1mm. The milk skin yogurt provided by the present invention has obvious stratification and novel state, and the yogurt has a stable texture, and will not have top layer water separation phenomenon during the shelf life. At the same time, it also has a delicate taste and rich milk flavor.

[0046] The beneficial effects of the present invention are further illustrated below in conjunction with embodiments.

[0047] In order to make the invention purpose, technical scheme and beneficial technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with examples. However, it should be understood that the examples of the present invention are only for explaining the present invention, not for limiting the present invention, and the examples of the present invention are not limited to the examples given in the specification. The specific experimental conditions or operating conditions not specified in the examples are made under conventional conditions, or are made under the conditions recommended by the material supplier.

[0048] In the following examples, the reagents, materials and instruments used are all commercially available unless otherwise specified.

[0049] Specifically, in the following embodiments and comparative examples of the present application:

[0050] The stabilizer is a combination of gelatin and pectin LM-106, wherein the gelatin comes from Danisco China Ltd. and the pectin comes from CP Kelco China Ltd.

[0051] The sweetener is white sugar.

[0052] The fermentation agent is Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus, purchased from Danisco (China) Co., Ltd., and the Latin names are Lactobacillus delbrueckii subsp. bulgaricus; Streptococcus salivarius subsp. thermophilus.

[0053] Egg yolk powder comes from Taiyo Chemical Co., Ltd.

[0054] Milk protein powder CH-7430 comes from Arla Food Ingredients Co., Ltd.

[0055] In the following examples and comparative examples, unless otherwise specified, the fermentation is completed when the acidity of the product reaches 70-75°F.

[0056] Example 1

[0057] This embodiment provides a specific milk skin yogurt and a preparation method.

[0058] The raw materials of the milk yogurt are: based on the total weight of all the raw materials, the content of butter is 3wt%, the content of cream is 3wt%, the content of egg yolk powder is 0.2wt%, the content of milk protein powder is 0.5wt%, the content of white sugar is 6wt%, the content of pectin is 0.05wt%, the content of gelatin is 0.2wt%, the content of starter is 0.005wt%, and the content of raw milk is 100wt%.

[0059] The preparation method is specifically:

[0060] 1) Heat 1 / 3 of the total amount of raw milk to 50°C, then add premixed milk protein powder, white sugar, pectin and gelatin, keep warm and stir for 10 minutes; then heat to 60°C and homogenize at 80bar;

[0061] 2) The homogenized material in step 1) is heated to 85° C. for a second time, and the remaining raw milk, egg yolk powder, cream and butter are added, and stirred for a second time for 20 minutes until they are completely dissolved; pasteurization is performed under the conditions of: a sterilization temperature of 97° C. and a sterilization time of 5 minutes; and then cooled to 40° C.

[0062] 3) Adding the fermentation agent to the material cooled in step 2) by aseptic addition, stirring evenly and filling into each packaging cup; placing the packaging cup stably in a 40°C hot storage for fermentation, and moving the product into a 4°C cold storage after the acidity reaches 70°T, and obtaining the milk skin yogurt after 24 hours.

[0063] Example 2

[0064] This embodiment provides a specific milk skin yogurt and a preparation method.

[0065] The raw materials of the milk yogurt are: based on the total weight of all the raw materials, the butter content is 2wt%, the cream content is 5wt%, the egg yolk powder is 0.1wt%, the milk protein powder is 0.1wt%, the white sugar is 8wt%, the pectin is 0.2wt%, the gelatin is 0.1wt%, the starter is 0.002wt%, and the raw milk is supplemented to 100wt%.

[0066] The preparation method is specifically:

[0067] 1) Heat 1 / 3 of the total amount of raw milk to 54°C, then add premixed milk protein powder, white sugar, pectin and gelatin, keep warm and stir for 15 minutes; then heat to 65°C and homogenize at 100 bar;

[0068] 2) The homogenized material in step 1) is heated to 75° C. for a second time, and the remaining raw milk, egg yolk powder, cream and butter are added, and stirred for a second time for 15 minutes until they are completely dissolved; pasteurization is performed under the conditions of: a sterilization temperature of 93° C. and a sterilization time of 7 minutes; and then cooled to 43° C.

[0069] 3) Adding the starter to the cooled material in step 2) by aseptic addition, stirring evenly and filling into each packaging cup; placing the packaging cup steadily in a 43° C. hot storage for fermentation, and moving the product into a 6° C. cold storage after the acidity reaches 75° T, and obtaining the milk skin yogurt after 24 hours.

[0070] Example 3

[0071] This embodiment provides a specific milk skin yogurt and a preparation method.

[0072] The raw materials of the milk yogurt are: based on the total weight of all the raw materials, the butter content is 2.5wt%, the cream is 4wt%, the egg yolk powder is 0.2wt%, the milk protein powder is 0.7wt%, the white sugar is 8wt%, the pectin is 0.1wt%, the gelatin is 0.1wt%, the starter is 0.002wt%, and the raw milk is supplemented to 100wt%.

[0073] The preparation method is specifically:

[0074] 1) The process is the same as step 1) in Example 1;

[0075] 2) The process is the same as step 2) in Example 1, except that the pasteurization conditions are: the pasteurization temperature is 95°C, the pasteurization time is 5 minutes; and then cooled to 42°C.

[0076] 3) Adding the fermentation agent to the material cooled in step 2) by aseptic addition, stirring evenly and filling into each packaging cup; placing the packaging cup stably in a 42° C. hot storage for fermentation, and moving the product into a 4° C. cold storage after the acidity reaches 75° T, and obtaining the milk skin yogurt after 24 hours.

[0077] Comparative Example 1

[0078] This comparative example provides a specific milk skin yogurt and a preparation method thereof. The raw materials of the milk skin yogurt are the same as those in Example 1.

[0079] The specific process of the preparation method is the same as that of Example 1, except that no homogenization treatment is performed after the first heating.

[0080] Comparative Example 2

[0081] This comparative example provides a specific milk skin yogurt and a preparation method thereof. The raw materials of the milk skin yogurt are the same as those in Example 1.

[0082] The specific process of the preparation method is the same as that of Example 1, except that all the raw materials are added at one time instead of adding them step by step. Specifically:

[0083] 1) Heat the raw milk to 50°C, then add the pre-mixed milk protein powder, white sugar, pectin, gelatin, egg yolk powder, cream and butter, and stir for 10 minutes; then heat to 60°C and homogenize at 80 bar.

[0084] 2) Pasteurization was performed under the following conditions: the sterilization temperature was 97°C and the sterilization time was 5 min; and then the mixture was cooled to 40°C.

[0085] 3) The specific process is the same as step 3) in Example 1.

[0086] Comparative Example 3

[0087] This comparative example provides a specific milk yogurt and a preparation method thereof. The raw materials of the milk yogurt are: no butter is used, and the quality of the butter is replaced by raw milk. Other raw materials are the same as those in Example 1.

[0088] The specific process of the preparation method is the same as that of Example 1.

[0089] Comparative Example 4

[0090] This comparative example provides a specific milk yogurt and a preparation method thereof. The raw materials of the milk yogurt are: 6wt% butter, 0wt% cream, and other raw materials are the same as those in Example 1.

[0091] The specific process of the preparation method is the same as that of Example 1

[0092] Effect Example

[0093] The inventors conducted effect tests on the yogurts prepared in Examples 1 to 3 and Comparative Examples 1 to 4 of the present application, including the test and evaluation of the appearance, taste, and texture (tissue state) of the yogurts. The specific results are shown in Tables 1 and 3.

[0094] Table 1 shows the appearance evaluation of the yogurts prepared in Examples 1 to 3 and Comparative Examples 1 to 4 of the present application.

[0095] Tables 2 and 3 are sensory evaluations of the yogurts prepared in Examples 1 to 3 and Comparative Examples 1 to 4 of the present application, wherein the sensory evaluation mainly includes the evaluation of the taste and texture (tissue state) of the yogurt, and the sensory scoring standard is shown in Table 2; 30 people participated in this experiment, and the sensory scoring items were averaged. The higher the score, the closer it is to the optimal characteristics of the product, and the test subjects' liking for the product was statistically analyzed. The specific sensory scoring results are shown in Table 3.

[0096] Table 1

[0097]

[0098] As can be seen from Table 1, the milk skin yogurts prepared from Examples 1 to 3 show that the technical solution of the present application can obtain milk skin yogurt with obvious stratification, and the top layer is a golden milk skin with a thickness greater than 1 mm, and the lower layer is a solidified yogurt. However, as can be seen from Example 1 and Comparative Example 2, if the stepwise addition of raw materials is not adopted during the preparation process, the yogurt stratification is not obvious, and the preset milk skin yogurt state cannot be obtained; as can be seen from Example 1 and Comparative Example 3, the choice of butter is specific. If butter is not added, the milk skin will be too thin, and the color will not be golden or light, and the preset milk skin yogurt state cannot be obtained.

[0099] Table 2

[0100]

[0101] Table 3

[0102]

[0103] It can be seen from Tables 2 and 3 that the milk skin yogurt provided by the technical solution of the present invention has a delicate and smooth taste, a rich cream flavor, and a uniform and delicate yogurt texture. There is no whey precipitation during the shelf life. The product concept is highly consistent and can be loved by consumers.

[0104] It can be seen from Example 1 and Comparative Example 1 that when homogenization is not performed during the preparation process, the final product will have a rough texture and the top layer will easily precipitate water during the shelf life. This may be because pectin and gelatin cannot be fully dissolved and dispersed during the preparation process; it will also affect the taste of the yogurt product.

[0105] It can be seen from Example 1 and Comparative Example 2 that if the method of adding raw materials step by step is not adopted during the preparation process, the yogurt layers are not obvious and the preset milk skin yogurt state cannot be obtained.

[0106] It can be seen from Example 1 and Comparative Examples 3 and 4 that the selection and proportion of raw materials in the present application are specific and cannot be adjusted at will. If butter is not added, the milk skin will be too thin, and the color will be non-golden and light, and the preset milk skin yogurt state cannot be obtained; if too much butter is added and too little cream is added, the taste and flavor of the yogurt will be affected, making the final product lack the fragrance of milk fat, the taste will be sticky, and the tasting result will be unsatisfactory.

[0107] In summary, the milk skin yogurt provided by the technical solution of the present application has a layered effect of golden milk skin compared with the solidified yogurt in the prior art, and the yogurt has a smooth taste and rich cream flavor. Its novel texture and unique flavor are more likely to be liked by consumers.

[0108] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A milk skin yogurt, characterized in that: The milk skin yogurt has an obvious layered structure, with the upper layer being the milk skin and the lower layer being the yogurt; the milk skin is golden yellow.

2. The milk skin yogurt according to claim 1, characterized in that Based on the total weight of the raw materials of the milk yogurt, the milk yogurt includes the following raw materials: 2-3wt% butter, 3-5wt% cream, 0.1-0.2wt% egg yolk powder, 0.1-1wt% milk protein powder, 6-8wt% sweetener, 0.05-0.4wt% stabilizer, 0.002-0.005wt% starter, and the balance is raw milk; and / or, the thickness of the milk skin is greater than 1 mm; And / or, the acidity of the milk skin yogurt is 70-75°T.

3. The milk skin yogurt according to claim 2, characterized in that: The butter has a fat content of more than 95 wt%; And / or, the fat content of the cream is 35-40wt%; And / or, the cream is separated from whole milk; And / or, the protein content of the milk protein powder is above 75wt%; And / or, the sweetener is selected from one or more of white sugar, fructose syrup, maltose, erythritol, and stevioside; And / or, the stabilizer is selected from one or a combination of pectin, gelatin and diacetyl tartaric acid mono- and diglycerides; And / or, the fermentation agent is selected from one or more of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus.

4. The milk skin yogurt according to claim 3, characterized in that: The stabilizer is selected from a compound of pectin and gelatin, and the mass ratio of the pectin to the gelatin is (1-2): (1-4).

5. A method for preparing the milk skin yogurt according to any one of claims 1 to 4, characterized in that: The steps include: 1) mixing the milk protein powder, sweetener and stabilizer evenly, adding the first raw milk, stirring and homogenizing at a temperature of 100°; 2) heating the homogenized material in step 1) to a second temperature, then adding the second raw milk, egg yolk powder, cream and butter, stirring until completely dissolved, sterilizing and cooling; 3) adding a leavening agent to the cooled material in step 2), stirring the material evenly, canning the material, and fermenting the material at a constant temperature. After the fermentation is completed, cooling the material to obtain the milk yogurt.

6. The preparation method according to claim 5, characterized in that: The first raw milk refers to 1 / 3 to 2 / 3 of the total raw milk. And / or, in step 1), the temperature of the first raw milk is 50-55° C.; And / or, the second raw cow's milk refers to 1 / 3 to 2 / 3 of the total raw cow's milk.

7. The preparation method according to claim 5, characterized in that: The time of heat preservation and stirring is 10 to 15 minutes; And / or, the homogenization temperature is 60-65°C; And / or, the homogenization pressure is 80-100 bar.

8. The preparation method according to claim 5, characterized in that: The second temperature is 75-85°C; And / or, the sterilization temperature is 93-97°C and the sterilization time is 5-7min; And / or, the cooling is to fermentation temperature.

9. The preparation method according to claim 5, characterized in that: The constant temperature fermentation temperature is 40-43°C, and the fermentation is completed when the temperature reaches 70-75°F; And / or, the temperature is lowered to 4-6°C after fermentation is completed.

10. A milk skin yogurt, characterized in that: The preparation is obtained by the preparation method according to any one of claims 5 to 9.

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