High-protein low-sensitivity flavored fermented milk and preparation method thereof

Abstract

The invention discloses high-protein low-sensitivity flavored fermented milk and a preparation method thereof.The fermented milk is prepared from, by mass, 90-95 parts of concentrated milk, 5-10 parts of fruit and vegetable juice, 0.02-0.5 part of lactase, 0.01-0.2 part of glucose oxidase and a leavening agent, and the dosage of the leavening agent is 5-20 U per 100 parts of concentrated milk and fruit and vegetable juice. The fruit and vegetable juice comprises apple juice, red date juice and turmeric juice in a mass ratio of (1-3): (2-5): (2-5). According to the high-protein low-allergy flavored fermented milk disclosed by the invention, the concentrated milk is taken as a raw material, and the lactase and the fruit and vegetable juice are added, so that the obtained high-protein low-allergy flavored fermented milk is excellent in flavor characteristic, good in tissue state, high in viable count and long in shelf life, retains the original nutritional ingredients in the fresh milk as far as possible, also has a certain low-allergy effect, is suitable for specific people to drink, and has a good market prospect. The problem that consumers worry about the white granulated sugar and the stabilizer is solved, and the protein content of the obtained fermented milk is 10-12 g / 100 g and is far higher than that of traditional fermented milk.

Description

Technical Field

[0001] The invention relates to a dairy product, in particular to a high-protein, low-allergy flavored fermented milk and a preparation method thereof. Background Art

[0002] Yogurt, as a fermented dairy product, is loved by consumers for its rich nutritional value, unique taste and easy digestion and absorption. However, traditional yogurt has certain limitations in protein content and cannot meet the needs of some specific groups of people (such as athletes, the elderly, patients in recovery, etc.) for high-protein diets, and also needs to avoid the problem of intestinal discomfort caused by high protein. Therefore, the development of a high-protein, low-allergy flavored fermented milk has important market value and social significance.

[0003] There are currently two ways to prepare high-protein yogurt. One is to remove whey or concentrate it through equipment, and the other is to add high-protein nutrients for strengthening. For example, patent CN109924257A discloses a low-fat, high-protein yogurt, which achieves the purpose of high protein by adding composite protein powder (concentrated whey protein, isolated whey protein, milk protein concentrate, casein, skim milk powder); CN117461690A discloses a method for preparing low-sugar, high-protein milk products, which increases the protein content in the product by ultrafiltration and nanofiltration membrane treatment; CN116918865A discloses a method for preparing low-fat, high-protein fermented milk, that is, using ceramic microfiltration membranes to treat raw milk, and using rennet to remove whey from semi-finished products to prepare concentrated milk; CN114831178A discloses a method for preparing concentrated high-protein yogurt before fermentation, that is, using spray drying to treat MPC or MCC concentrate to obtain a high-protein base material; CN110870504A discloses a high-protein, additive-free yogurt, which is prepared by separating the whey from yogurt using a separator; CN112438313A discloses a yogurt and its preparation process, which is prepared by heat shock treatment and frame membrane concentration treatment.

[0004] However, the domestic whey processing technology is not perfect, and the discharged whey is a waste for enterprises and a pressure on the environment. The yogurt system prepared by direct concentration is unstable, and stabilizers are usually needed to stabilize the system. However, the use of stabilizers may affect the metabolic function of the human body and cover up the adverse characteristics of food, causing certain health risks to the human body. Summary of the invention

[0005] In view of the problem that the fermented milk system prepared directly from concentrated milk is unstable and the use of stabilizers will bring health risks, the present invention provides a high-protein, low-allergy flavored fermented milk and a preparation method thereof, and uses fruit and vegetable juice with specific ingredients instead of stabilizers, which not only helps to improve the naturalness and health attributes of dairy products, but also meets the pursuit of modern consumers for cleaner and healthier food labels.

[0006] In order to achieve the above-mentioned object, the present invention provides a high-protein, low-allergy flavored fermented milk, which is prepared from raw materials including the following components, by weight: 90-95 parts of concentrated milk, 5-10 parts of fruit and vegetable juice, 0.02-0.5 parts of lactase, 0.01-0.2 parts of glucose oxidase, and a starter, wherein the amount of the starter is 5U-20U per 100 parts of concentrated milk and fruit and vegetable juice, and the fruit and vegetable juice includes apple juice, red date juice and turmeric juice in a mass ratio of (1-3): (2-5): (2-5).

[0007] The present invention achieves the effect of significantly increasing the protein content in fermented milk by using concentrated milk, utilizes fruit and vegetable juice to stabilize the fermented milk system and give the product a unique flavor, utilizes lactase to reduce the body's lactose discomfort and reduce glycosylation reactions (protein oxidation, affecting stability and nutritional value), and utilizes glucose oxidase to assist in extending the product's storage period.

[0008] Among fruit and vegetable juices, apple juice is rich in pectin, dietary fiber, vitamins, minerals, fructose, polyphenols and other nutrients; red date juice is rich in vitamins, dietary fiber, sugar, polyphenols and other nutrients; turmeric juice is rich in curcumin, dietary fiber, starch, polyphenols and other nutrients.

[0009] The pectin, polyphenols, dietary fiber, starch, curcumin and other nutrients provided by the compound fruit and vegetable juice have certain effects. Among them, pectin will be adsorbed on casein, increase the steric hindrance of casein-phosphate polymer, and increase the weak network structure of casein; the cross-linked ester bonds between starch molecules improve the resistance of the fermented milk system to heat, acid and mechanical effects, and have a certain swelling property to prevent whey precipitation in the later stage; curcumin will increase the number and strength of hydrogen bonds in the gel network structure and improve the water holding capacity of the system. In addition, the pH of fruit and vegetable juice affects the performance of protein. The appropriate proportion of fruit and vegetable juice can also reduce the sensitivity of casein to calcium in a high calcium environment and avoid the occurrence of precipitation and precipitation.

[0010] The high-protein, low-allergy flavored fermented milk of the present invention uses concentrated milk as a raw material. By adding lactase and fruit and vegetable juice, the obtained high-protein, low-allergy flavored fermented milk has excellent flavor characteristics, good tissue state, high live bacteria count, and long shelf life. It retains the original nutrients in fresh milk as much as possible and also has a certain low-allergy effect, and is suitable for drinking by specific groups of people.

[0011] The above apple juice, red date juice and turmeric juice are compounded with pure fruit juices on the market, or they can be made at home. Fresh apples, red dates and turmeric are washed, squeezed into juice, sieved to remove residue, and pure fruit and vegetable juice is obtained.

[0012] Preferably, the A2-β casein content in the concentrated milk is 36-40 g / L, the specific gravity of the concentrated milk is 1.12-1.15 g / mL, the protein content is 11-12 g / 100 mL, and the fat content is 6-8 g / 100 mL.

[0013] In the above technical scheme, by limiting these parameters, on the one hand, the consistency of the quality of the concentrated milk product after the concentration process is guaranteed; on the other hand, it also ensures that the product prepared from the concentrated milk under this parameter can achieve the necessity of high-protein, low-allergy yogurt, and limiting fat is to ensure product stability. If it is too low, the flavor will not be strong, and if it is too high, the system will be unstable, avoiding abnormal situations such as protein precipitation and fat floating.

[0014] Preferably, the concentrated milk is prepared by concentrating fresh milk rich in A2-β casein, wherein the A2-β casein content in the fresh milk is ≥9.0 g / L. The purpose of selecting fresh milk rich in A2-β casein as a raw material is to reduce protein allergies.

[0015] Preferably, the fermentation agent includes human fermentation lactobacillus grx07, Lactobacillus plantarum YDKY001, Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium in a ratio of (1-2): (1-2): (3-5): (4-6): (3-6).

[0016] The human-derived Lactobacillus fermentum grx07 is the human-derived Lactobacillus fermentum grx07 disclosed in the invention patent with application publication number CN103937716A.

[0017] Lactobacillus plantarum YDKY001 is the Lactobacillus plantarum YDKY001 disclosed in the invention patent with application publication number CN107674852A.

[0018] In the above technical scheme, the use of a multi-strain compound starter not only increases the content of live bacteria in the final product, but also improves the flavor and taste of the fermented milk, and also has a certain regulatory effect on the fermentation time and acidity.

[0019] Preferably, the fruit and vegetable juice comprises apple juice, red date juice and turmeric juice in a mass ratio of 2:3:4. The use of fruit and vegetable juice in this ratio can significantly improve key indicators such as the flavor and taste of fermented milk, fermentation time and number of viable bacteria.

[0020] The second aspect of the present invention provides a method for preparing the above-mentioned high-protein, low-allergy flavored fermented milk, which comprises the following steps: 1) Preheat the concentrated milk to 50-60°C and stir with the fruit and vegetable juice for 5-10 minutes to obtain liquid A; 2) The liquid A obtained in step 1) is sterilized at 95°C for 5 minutes, cooled to 40°C, and then a starter is added, and lactase is added, and fermented until the end point acidity is 70-80°T, and the fermentation is terminated; 3) Demulsifying the product fermented to the end point in step 2), adding glucose oxidase, stirring and then filling; 4) The finished product filled in step 3) is transferred to a cold storage at 2-6℃ and refrigerated for 8-12 hours.

[0021] The present invention adds the fruit and vegetable juice into the concentrated milk before fermentation, which plays a role in stabilizing the system.

[0022] Specifically, the preparation method of the concentrated milk is as follows: the raw milk is subjected to a milk purification standardization treatment, and then subjected to double-effect vacuum concentration to obtain the concentrated milk.

[0023] Furthermore, the conditions of the double-effect vacuum concentration are: sterilization temperature 85-88°C, first-effect concentration temperature 55-60°C, first-effect concentration vacuum degree 0.08-0.085Mpa, second-effect concentration temperature 45-50°C, second-effect concentration vacuum degree 0.09-0.095Mpa. Through this concentration method, only the water in the raw milk is removed, and the nutrients in the raw milk are retained as much as possible; in addition, a certain caramel flavor (with a certain Maillard reaction) can be given to the product, which improves the quality of the later products.

[0024] Through the above technical solution, the present invention achieves the following beneficial effects: 1. The high-protein, low-allergy flavored fermented milk of the present invention uses concentrated milk as a raw material. By adding lactase and fruit and vegetable juice, the obtained high-protein, low-allergy flavored fermented milk has excellent flavor characteristics, good tissue state, high number of viable bacteria, and long shelf life. It retains the original nutrients in fresh milk as much as possible and also has a certain low-allergy effect. It is suitable for drinking by specific groups of people and solves consumers' concerns about white sugar and stabilizers. The obtained fermented milk has a protein content of 10-12 g / 100g, which is much higher than traditional fermented milk.

[0025] 2. The present invention provides a preparation process for high-protein, low-allergy flavored fermented milk. By optimizing the preparation process and parameters, the problems of high-protein fermented milk being easy to agglomerate, having poor flavor, and causing gastrointestinal discomfort after drinking are solved. The prepared high-protein, low-allergy flavored fermented milk has good taste and stable texture, and the content of characteristic flavor substances such as methylpyrazine (burnt aroma) accounts for up to 25 μg / L.

[0026] 3. The high-protein, low-allergy flavored fermented milk provided by the present invention provides the product with a variety of nutrients due to the addition of fruit and vegetable juice, adjusts the taste of the fermented milk, makes it more in line with the taste of consumers, and has a longer storage period. DETAILED DESCRIPTION

[0027] The specific implementation of the present invention is described in detail below in conjunction with the examples. It should be understood that the specific implementation described herein is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0028] In the following embodiments, Fruit and vegetable juice source: Wash fresh apples, red dates, and turmeric, squeeze the juice, pass through 200 mesh to remove the residue, and get pure fruit and vegetable juice for later use; Lactase was purchased from Shandong Aicai Biotechnology Co., Ltd.; Glucose oxidase was purchased from Shandong Aicai Biotechnology Co., Ltd.

[0029] Example 1 The preparation method of high-protein low-allergy flavored fermented milk comprises the following steps: 1) After the raw milk is subjected to standardization treatment, it is subjected to double-effect vacuum concentration, with the first-effect concentration temperature being 55°C, the first-effect concentration vacuum being 0.08Mpa, and the second-effect concentration temperature being 45°C, and the second-effect concentration vacuum being 0.09Mpa, to obtain concentrated milk; 2) Preheat 9 kg of concentrated milk to 50°C and stir with 1 kg of fruit and vegetable juice (the fruit and vegetable juice includes apple juice, red date juice and turmeric juice in a mass ratio of 1:2:2) for 5-10 minutes to obtain liquid A; 3) The liquid A obtained in step 2) was sterilized at 95°C for 5 min, cooled to 40°C, and then 500U of starter (the starter included human fermentation lactobacillus grx07, plant lactobacillus YDKY001, thermophilic streptococcus, acidophilus lactobacillus, and bifidobacterium in a ratio of 1:1:3:4:6) was added, and 2g of lactase was added, and the fermentation was continued until the end point acidity was 70°T, and the fermentation was terminated; 4) Demulsifying the product fermented to the end point in step 3), adding 1 g of glucose oxidase, stirring and then filling; 5) The finished product filled in step 4) is transferred to a 2℃ cold storage and refrigerated for 8 hours.

[0030] Example 2 The preparation method of high-protein low-allergy flavored fermented milk comprises the following steps: 1) The raw milk is subjected to a standardization treatment and then subjected to double-effect vacuum concentration, with the first-effect concentration temperature at 60°C and the first-effect concentration vacuum degree at 0.085Mpa, and the second-effect concentration temperature at 50°C and the second-effect concentration vacuum degree at 0.095Mpa, to obtain concentrated milk; 2) Preheat 9.5 kg of concentrated milk to 60° C. and stir with 0.5 kg of fruit and vegetable juice (the fruit and vegetable juice includes apple juice, red date juice and turmeric juice in a mass ratio of 3:5:5) for 10 min to obtain liquid A; 3) The liquid A obtained in step 2) was sterilized at 95°C for 5 min, cooled to 40°C, and then 2000U of starter (the starter included human fermentation lactobacillus grx07, plant lactobacillus YDKY001, thermophilic streptococcus, acidophilus lactobacillus, and bifidobacterium in a ratio of 1:2:5:6:6) was added, and 50g of lactase was added, and fermented to an end point acidity of 80°T, and the fermentation was terminated; 4) Demulsifying the product fermented to the end point in step 3), adding 20 g of glucose oxidase, stirring and then filling; 5) The finished product filled in step 4) is transferred to a 6℃ cold storage and refrigerated for 12 hours.

[0031] Example 3 The preparation method of high-protein low-allergy flavored fermented milk comprises the following steps: 1) After the raw milk is subjected to standardization treatment, it is subjected to double-effect vacuum concentration, with the first-effect concentration temperature being 58°C, the first-effect concentration vacuum degree being 0.08Mpa, and the second-effect concentration temperature being 47°C, and the second-effect concentration vacuum degree being 0.095Mpa, to obtain concentrated milk; 2) Preheat 92 kg of concentrated milk to 55° C. and stir with 0.8 kg of fruit and vegetable juice (the fruit and vegetable juice includes apple juice, red date juice and turmeric juice in a mass ratio of 2:3:4) for 8 min to obtain liquid A; 3) The liquid A obtained in step 2) was sterilized at 95°C for 5 min, cooled to 40°C, and then 1000U of starter (the starter included human fermentation lactobacillus grx07, plant lactobacillus YDKY001, thermophilic streptococcus, acidophilus lactobacillus, and bifidobacterium in a ratio of 2:1:4:5:4) was added, and 25g of lactase was added, and the fermentation was terminated until the end point acidity was 75°T; 4) Demulsifying the product fermented to the end point in step 3), adding 10 g of glucose oxidase, stirring and then filling; 5) The finished product filled in step 4) is transferred to a 4℃ cold storage and refrigerated for 10 hours.

[0032] Comparative Example 1 Other conditions are the same as those in Example 3, except that fresh milk is used instead of concentrated milk.

[0033] Comparative Example 2 Other conditions were the same as those in Example 3, except that apple juice was not present.

[0034] Comparative Example 3 Other conditions are the same as those in Example 3, except that no red date juice is present.

[0035] Comparative Example 4 Other conditions were the same as those in Example 3, except that there was no turmeric juice.

[0036] Comparative Example 5 The other conditions were the same as those in Example 3, except that lactase was not present.

[0037] Comparative Example 6 Other conditions were the same as those in Example 3, except that glucose oxidase was not present.

[0038] Comparative Example 7 Other conditions were the same as those in Example 3, except that the leavening agent ratio was changed to 1:1:1:1:1.

[0039] Comparative Example 8 Other conditions were the same as those in Example 3, except that the fruit and vegetable juice was replaced with a stabilizer: a compound thickener S-031A (Shanghai Haoyue Food Technology Co., Ltd.).

[0040] Performance Testing Coagulation time, sensory evaluation: GB 19302; protein: GB 5009.5; methylpyrazine content: gas chromatography; yogurt lactic acid bacteria content: GB 4789.35. The results are shown in Table 1.

[0041] Table 1 Performance test results

[0042] From Table 1 we can see that: (1) The fermented milk prepared in Examples 1-3 has the advantages of mellow taste, high protein content, high characteristic flavor substances, high number of viable bacteria, and long storage period; (2) As can be seen from Comparative Example 1, the prepared yogurt has a thinner taste and lower flavor substances. This is mainly because the low protein content in the raw milk affects the taste of the final product, and the flavor characteristics are not obvious without the concentration process; (3) From Comparative Examples 2-4, it can be seen that fruit and vegetable juice plays an important role in the yogurt system. It is easy to have a granular feel. The type and ratio of fruit and vegetable juice have an impact on the coagulation time, viable bacteria count and storage period of fermented milk. (4) From Comparative Example 5, it can be seen that without adding sweetener, the product tastes bitter under the same fermentation process conditions; (5) Comparative Example 6 shows that due to the increase in various nutrients in high-protein fermented milk, it is easily affected by the concentration of ambient oxygen, etc., and the absence of glucose oxidase leads to a decrease in the storage period of the product; (6) From Comparative Example 7, it can be seen that the ratio of the starter has an impact on the coagulation time, characteristic flavor substances and lactic acid bacteria content; (7) From Comparative Example 8, it can be seen that the use of fruit and vegetable juice and compound stabilizer has better stabilization effect and a longer storage period, but fruit and vegetable juice can effectively shorten the fermentation time and increase the number of viable bacteria in the final product compared with the compound stabilizer.

[0043] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0044] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0045] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A high-protein, low-allergy flavored fermented milk, characterized in that: The invention is prepared from the following raw materials, measured by weight: 90-95 parts of concentrated milk, 5-10 parts of fruit and vegetable juice, 0.02-0.5 parts of lactase, 0.01-0.2 parts of glucose oxidase, and a starter, wherein the amount of the starter is 5U-20U per 100 parts of concentrated milk and fruit and vegetable juice, and the fruit and vegetable juice comprises apple juice, red date juice and turmeric juice in a weight ratio of (1-3):(2-5):(2-5).

2. The high-protein, low-allergy flavored fermented milk according to claim 1, characterized in that: The A2-β casein content in the concentrated milk is 35-40 g / L, the specific gravity of the concentrated milk is 1.10-1.15 g / mL, the protein content is 10-12 g / 100 mL, and the fat content is 4-8 g / 100 mL.

3. The high-protein, low-allergy flavored fermented milk according to claim 1, characterized in that: The concentrated milk is prepared by concentrating fresh milk rich in A2-β casein, wherein the content of A2-β casein in the fresh milk is ≥9.0 g / L.

4. The high-protein, low-allergy flavored fermented milk according to claim 1, characterized in that: The fermentation agent includes human fermentation lactobacillus grx07, plant lactobacillus YDKY001, thermophilic streptococcus, acidophilus lactobacillus, and bifidobacterium in a ratio of (1-2): (1-2): (3-5): (4-6): (3-6).

5. The high-protein, low-allergy flavored fermented milk according to claim 1, characterized in that: The fruit and vegetable juice comprises apple juice, red date juice and turmeric juice in a mass ratio of 2:3:

4.

6. The method for preparing high-protein, low-allergy flavored fermented milk according to any one of claims 1 to 5, characterized in that: The steps include: 1) Preheat the concentrated milk to 50-60°C and stir with the fruit and vegetable juice for 5-10 minutes to obtain liquid A; 2) sterilizing the liquid A obtained in step 1), cooling it to 40°C, adding a starter, and adding lactase, fermenting until the end point acidity is 70-80°T, and then ending the fermentation; 3) Demulsifying the product fermented to the end point in step 2), adding glucose oxidase, stirring and then filling; 4) The finished product filled in step 3) is transferred to a cold storage at 2-6℃ and refrigerated for 8-12 hours.

7. The preparation method according to claim 6, characterized in that: The preparation method of the concentrated milk comprises the following steps: subjecting raw milk to a milk purification standardization process, and then subjecting the raw milk to double-effect vacuum concentration to obtain the concentrated milk.

8. The preparation method according to claim 7, characterized in that: The conditions for the double-effect vacuum concentration are: sterilization temperature 80-88°C, first-effect concentration temperature 55-60°C, first-effect concentration vacuum degree 0.08-0.085Mpa, second-effect concentration temperature 45-50°C, second-effect concentration vacuum degree 0.09-0.095Mpa.

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