阅读说明：本技术 一种红薯发酵风味酸牛奶及其制备方法 (Sweet potato fermented flavored yoghurt and preparation method thereof ) 是由 郑英明 盛海波 丁俊 丁琦越 丁麒宇 于 2021-08-10 设计创作，主要内容包括：本发明涉及一种风味酸牛奶及其制备方法,特别是添加一种植物红薯的风味酸牛奶,属于乳品技术领域。本发明所提供的红薯发酵奶,其组分及重量比例如下：牛奶850—900Kg、红薯粉30Kg、白砂糖30Kg、乳化稳定剂3Kg、红薯香精0.4Kg、酸奶香精0.2Kg、奶油香精0.2Kg、菌种X1(10UC)配料总量1000Kg。本发明将牛奶与红薯粉有机结合,同时添加益生元菌种,得到一种营养均衡,有利于保护心脏、防止动脉粥样硬化,以及具有美容、减肥功能的发酵风味酸牛奶。(The invention relates to flavored yoghurt and a preparation method thereof, in particular to flavored yoghurt added with a plant sweet potato, belonging to the technical field of dairy products. The sweet potato fermented milk provided by the invention comprises the following components in parts by weight: 850-900Kg of milk, 30Kg of sweet potato powder, 30Kg of white granulated sugar, 3Kg of emulsion stabilizer, 0.4Kg of sweet potato essence, 0.2Kg of yoghurt essence, 0.2Kg of cream essence, and 1000Kg of the total amount of the ingredients of strain X1(10 UC). According to the invention, milk and sweet potato powder are organically combined, and prebiotics strain is added, so that the fermented flavored yoghurt which is balanced in nutrition, beneficial to protecting the heart, preventing atherosclerosis, and has the functions of beautifying and losing weight is obtained.)

1. Sweet potato fermented flavored yoghurt is characterized by comprising the following components in parts by weight:

850 Kg of milk, 30Kg of sweet potato powder, 30Kg of white granulated sugar, 3Kg of emulsion stabilizer, 0.4Kg of sweet potato essence, 0.2Kg of yoghurt essence, 0.2Kg of cream essence and strain X1, wherein the milk is added with all the components and then the volume is fixed to 1000Kg with milk.

2. The fermented flavored yogurt of claim i, wherein the sweet potato is prepared by cleaning, peeling, shredding, color-protecting, drying and crushing sweet potato, and the moisture content is below 6%.

3. The fermented flavored yogurt of claim 1, wherein the emulsion stabilizer comprises glycerol monostearate, acetylated distarch phosphate, sodium tripolyphosphate, sodium alginate, gellan gum.

4. The fermented flavored yogurt of claim 1, characterized by: the essence comprises the following components in percentage by weight: 0.2kg of yoghourt essence, 0.4kg of sweet potato essence and 0.2kg of cream essence.

5. The method of preparing fermented flavored yogurt according to any of claims 1-4, characterized by the steps of: raw milk detection, raw milk standardization, batching, quantitative mixing, homogenizing sterilization, inoculation, fermentation, emulsion breaking, filling and secondary fermentation.

6. The method of preparing fermented flavored yogurt according to claim 5, wherein the batching step is: dissolving sweet potato powder in water, soaking, hydrolyzing with high temperature resistant alpha-amylase, saccharifying with saccharifying enzyme; wherein the addition amount of the high-temperature resistant alpha-amylase is 40U/g, the temperature is 95 ℃, and the time is 2.5 h; saccharification and enzymolysis conditions: pH5.0, enzyme adding amount of 424U/g, enzymolysis time of 4.1h, and enzymolysis temperature of 58 ℃.

7. The method of preparing fermented flavored yogurt according to claim 5, wherein the raw milk detection step is: the 72 DEG T alcohol protein is stable, the acidity is less than or equal to 18 DEG T, and the boiling is normal; detecting fat, protein, non-fat milk solids and antibiotic residues; the milk temperature is less than or equal to 4 ℃.

8. The method of preparing fermented flavored yogurt according to claim 5, wherein the raw milk is standardized by the steps of: milk temperature 45-50 ℃ and cycle time 10 minutes, standardized protein, fat and milk solids not fat must meet the specified requirements: protein is more than or equal to 2.8%, fat: not less than 3.1%, milk solids not fat: not less than 8.1 percent.

9. The method of preparing fermented flavored yogurt according to claim 5, wherein the batching step is: heating appropriate amount of milk to 55-60 deg.C, slowly adding mixture of stabilizer and 5-6 times of white sugar while stirring, stirring under heat preservation to dissolve completely, adding the rest white sugar and other adjuvants, and stirring to dissolve completely.

10. The method of preparing fermented flavored yogurt according to claim 5, wherein the mixing and quantifying steps are: adding the rest milk and the sweet potato liquid after enzymolysis, and mixing to 1000 Kg.

11. The method of claim 5, wherein the homogenizing and sterilizing step comprises: homogenizing the materials at 18-20MPa/65-70 deg.C, and sterilizing at 95 deg.C/300 s.

12. The method for preparing fermented flavored yogurt according to claim 5, wherein the steps of inoculation, fermentation, demulsification, filling and secondary fermentation are as follows: sterilizing, cooling to 42-43 deg.C, adding lactic acid bacteria starter X1 into milk, stirring to disperse uniformly, and stopping stirring and fermenting to acidity of 70 ° T.

13. The method of preparing fermented flavored yogurt of claim 5, wherein the demulsification is cooled to 18-22 ℃; filling and transferring to a cold storage at 2-6 ℃ for secondary fermentation.

Technical Field

The invention relates to the technical field of dairy products, in particular to sweet potato fermented flavored yoghurt and a preparation method thereof.

Background

Sweet potatoes (Sweet Potato), also called Sweet potatoes, Sweet potatoes and the like, are health food which can be used as both medicine and food. The sweet potato has different nutrient components, and various nutrient components have health care effect.

Mingdi Li Shizhen called sweet potato in Ben Cao gang mu to tonify deficiency, benefit strength, strengthen spleen and stomach, strengthen kidney yin, ancient agricultural book Jinshu Erxian Lu has six beneficial discussions of sweet potato treating disease. The sweet potato is used for treating nyctalopia caused by vitamin A deficiency, constipation, cellulitis, blood deficiency and other symptoms.

Modern nutrition theory shows that: the sweet potato is rich in vitamin, mineral, dietary fiber and other nutritional factors.

(1) Sweet potato is rich in vitamin B1, B2, E and vitamin A source. The sweet potato contains 6 times of vitamins B1 and B2 and 2 times of flour. The B vitamins are cofactors of various enzymes in amino acid metabolism and sugar metabolism. Vitamin B1 is deficient, sugar metabolism is incomplete, and excitation, fatigue, muscular atrophy, paralysis, heart failure and the like easily occur in the neuromuscular system. Vitamin B2 deficiency, stomatitis, glossitis, visual deterioration, cataract, keratitis, scrotitis, and seborrheic dermatitis. Vitamin E, also known as tocopherol, is a potent antioxidant. Has antiaging and human reproductive function maintaining effects, and also has skeletal muscle, smooth muscle and cardiac muscle structure maintaining effects. The sweet potato is also rich in carotene which is a vitamin A source, and the content of the vitamin A can be as high as 40mg/100 g. Carotene can be converted into vitamin A after being absorbed by human body, and the vitamin A can maintain normal visual function.

(2) The sweet potato is rich in minerals such as calcium, phosphorus, ferrum, selenium, etc. Calcium and phosphorus are important components of bones, and phosphorus is a component of proteins. Iron is a characteristic component of hemoglobin. Selenium is an element having important influence on immunity, has the effects of stimulating the production of immune globulin and antibody, and has the effects of preventing cancer, preventing arteriosclerosis and resisting aging.

(3) Sweet potatoes are also rich in dietary fiber (called seventh nutrient). The dietary fiber contained in the sweet potato is 10 times of that of rice flour, has fine texture, does not hurt intestines and stomach, can accelerate the peristalsis of the digestive tract, is beneficial to defecation, clears the digestive tract, shortens the detention time of toxic substances in food in the intestinal tract, reduces the self-poisoning of the human body caused by constipation, reduces the concentration of intestinal carcinogens, and prevents hemorrhoids and colorectal cancer. At the same time, cellulose can absorb a part of glucose, so that the sugar content in blood is reduced, and the preparation is helpful for preventing diabetes.

Yoghurt (Yoghurt) is a milk-like product obtained by inoculating Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus in milk and fermenting, and the finished product contains a large amount of corresponding viable bacteria. It is appreciated by consumers with its unique flavor and high nutritional value and health care function.

(1) The carbohydrate, fat and protein in the yoghourt are easy to digest and metabolize. The carbohydrate in the milk is lactose which is the main ingredient and accounts for about 4.5 percent, and 20 to 30 percent of the carbohydrate in the milk is changed into lactic acid and other organic acids such as benzoic acid, citric acid, acetic acid, butyric acid and the like after being prepared into the yoghurt. The generated sour substances not only can supply energy to the organism, but also have the nutrition and physiological functions. Due to the fermentation effect of the lactic acid bacteria, the lactose content in the yoghourt is greatly reduced, the yoghourt can be taken by people lack of lactase in vivo, and the so-called lactose intolerance symptoms such as diarrhea, nausea and the like which are caused when the people drink the milk can not occur. The yoghourt contains about 3% of fat, and the fat balls are small and easy to digest; the low-grade fatty acid is high in content and easy to metabolize; the content of essential fatty acid is high; in addition, the lipid in the yoghourt is acted by the lactobacillus lipase, so that not only is a small amount of free fatty acid generated, but also the structure of the fat is changed, and the yoghourt is easy to digest and absorb. The protein in the milk is fermented by lactic acid bacteria, and can be changed into fine coagulum, so that the milk is easier to digest. Free amino acids are increased by 4 times compared with milk, and polypeptides are increased, so that the milk is easily affected by digestive enzymes and is easy to absorb.

(2) The yoghourt contains rich fat-soluble vitamin A, D, E, beta-carotene and the like; due to the fermentation effect of lactobacillus, a large amount of B vitamins such as vitamin B1, B2, B5 and the like can be synthesized; the mineral elements have high K and P contents and slightly low Fe and I contents.

(3) The yogurt has strong antibacterial activity, and can inhibit growth of harmful bacteria, so that beneficial bacteria such as Bacillus acidophilus and Bacillus bifidus are dominant. The acidophilic bacillus can produce organic acid and antibiotic substance, and the bifidobacteria has the functions of preventing constipation, preventing and treating bacterial diarrhea, maintaining the balance of intestinal flora, synthesizing vitamin B group, etc.

(4) The yogurt can reduce cholesterol content in blood serum, and prevent cardiovascular diseases. Research proves that the edible yoghourt can reduce the cholesterol content in serum, and the absorption and the propagation of the lactic acid bacteria in the intestinal tract are interfered, so that the absorption of the small intestinal wall to the cholesterol is interfered.

(5) The yogurt has anti-tumor effect. Indole, nitrous acid, nitrosamine, azo compounds and the like generated by harmful bacteria in intestinal tracts have strong carcinogenicity. And through the action of lactic acid bacteria, intestinal flora can be adjusted, the excessive generation of harmful bacteria is inhibited, the concentration of various harmful substances (carcinogenic mutagens) is reduced, and the tumor incidence is reduced. Moreover, experiments also prove that after the yoghourt is eaten, the lactobacillus in the yoghourt has an activating effect on macrophages in the body and enhances the immunity of the organism, so the yoghourt has the effect of inhibiting cancer lesions.

The sweet potato is added into the yoghourt for fermentation, the advantages of the sweet potato and the yoghourt are integrated, and the dietary therapy value of the yoghourt is improved, so that the sweet potato yoghourt has a very wide development prospect. Meanwhile, the sweet potato yoghourt also combines the nutritional characteristics of animal food and plant food, realizes the nutritional balance of diet, and better meets the nutritional requirements of consumers. The development and production of the yoghourt enriches the varieties of the yoghourt in the market and maintains the health of people.

Disclosure of Invention

Based on the above, the sweet potato fermented flavored yoghurt and the preparation method thereof are needed, the milk and the sweet potato powder are organically combined, protein in the milk has a complementary effect on essential amino acid in grains, and simultaneously, the deficiency of carbohydrate in the milk is supplemented, so that the functional characteristics of the sweet potatoes are reflected in the fermented milk, and the flavored yoghurt with balanced nutrition and beneficial to heart protection is obtained.

In order to achieve the technical purpose, the invention provides the following technical scheme:

sweet potato fermented flavored yoghurt comprises the following components in parts by weight:

850 Kg of milk, 30Kg of sweet potato powder, 30Kg of white granulated sugar, 3Kg of emulsion stabilizer, 0.4Kg of sweet potato essence, 0.2Kg of yoghurt essence, 0.2Kg of cream essence and strain X1(10UC), wherein the milk is added with all the components and then the volume is fixed to 1000Kg with milk. Wherein the strain X1(10UC) is lactic acid bacteria starter produced by Hansen of Denmark.

In one embodiment, the sweet potato is prepared by cleaning sweet potato, peeling, shredding into pieces, protecting color, drying, and pulverizing, and has water content below 6%.

In one embodiment, the emulsion stabilizer comprises glycerol monostearate, acetylated distarch phosphate, sodium tripolyphosphate, sodium alginate and gellan gum.

In one embodiment, the essence comprises the following components in parts by weight: 0.2kg of yoghourt essence, 0.4kg of sweet potato essence and 0.2kg of cream essence.

The invention also provides a preparation method of the fermented flavored yoghourt, which comprises the following steps: raw milk detection, raw milk standardization, batching, quantitative mixing, homogenizing sterilization, inoculation, fermentation, emulsion breaking, filling and secondary fermentation.

In one embodiment, the burdening step is: dissolving sweet potato powder in water, soaking, hydrolyzing with high temperature resistant alpha-amylase, saccharifying with saccharifying enzyme; wherein the addition amount of the high-temperature resistant alpha-amylase is 40U/g, the temperature is 95 ℃, and the time is 2.5 h; saccharification and enzymolysis conditions: pH5.0, enzyme adding amount of 424U/g, enzymolysis time of 4.1h, and enzymolysis temperature of 58 ℃.

In one embodiment, the raw milk detection step is: the 72 DEG T alcohol protein is stable, the acidity is less than or equal to 18 DEG T, and the boiling is normal; detecting fat, protein, non-fat milk solids and antibiotic residues; the milk temperature is less than or equal to 4 ℃.

In one embodiment, the raw milk standardization step is: milk temperature 45-50 ℃ and cycle time 10 minutes, standardized protein, fat and milk solids not fat must meet the specified requirements: protein is more than or equal to 2.8%, fat: not less than 3.1%, milk solids not fat: not less than 8.1 percent.

In one embodiment, the burdening step is: heating appropriate amount of milk to 55-60 deg.C, slowly adding mixture of stabilizer and 5-6 times of white sugar while stirring, stirring under heat preservation to dissolve completely, adding the rest white sugar and other adjuvants, and stirring to dissolve completely.

In one embodiment, the mixing and quantifying steps are: adding the rest milk and the sweet potato liquid after enzymolysis, and mixing to 1000 Kg.

In one embodiment, the homogenizing and sterilizing step comprises: homogenizing the materials at 18-20MPa/65-70 deg.C, and sterilizing at 95 deg.C/300 s.

In one embodiment, the steps of inoculation, fermentation, demulsification, filling and secondary fermentation are as follows: sterilizing, cooling to 42-43 deg.C, adding lactic acid bacteria starter X1(10UC), stirring to disperse uniformly, and stopping stirring and fermenting to acidity of 70 ° T.

In one embodiment, the demulsification temperature is reduced to 18-22 ℃; filling and transferring to a cold storage at 2-6 ℃ for secondary fermentation.

In summary, the preparation process flow of the sweet potato fermented flavored yoghurt comprises the following steps:

1. detecting the raw milk, wherein the 72 DEG T alcohol protein is stable, the acidity is less than or equal to 18 DEG T, and the boiling is normal; detecting fat, protein, non-fat milk solid and antibiotic residue, wherein the milk temperature is less than or equal to 4 ℃;

2. standardizing raw milk, wherein the milk temperature is 45-50 ℃ and the circulation time is 10 minutes when the raw milk is standardized, and the standardized fat and non-fat milk solids must meet the specified requirements: protein is more than or equal to 2.8 percent, fat is more than or equal to 3.1 percent, and non-fat milk solid is more than or equal to 8.1 percent;

3. preparing sweet potato liquid, dissolving sweet potato powder in boiling water, soaking, hydrolyzing with amylase, saccharifying with saccharifying enzyme, wherein the addition amount of high temperature resistant alpha-amylase is 40U/g, the temperature is 95 ℃, and the time is 2.5 h; saccharification and enzymolysis conditions: pH5.0, enzyme adding amount of 424U/g, time of 4.1h and enzymolysis temperature of 58 ℃;

4. dissolving a stabilizer, heating a proper amount of milk to 55-60 ℃, slowly adding a mixture of the stabilizer and 5-6 times of white granulated sugar while stirring, keeping the temperature and stirring until the mixture is fully dissolved, adding the rest white granulated sugar and other auxiliary materials, and stirring until the mixture is fully dissolved;

5. mixing and quantifying, adding the rest milk and the hydrolyzed and enzymolyzed sweet potato liquid phase, and quantifying to 1000 Kg;

6. homogenizing and sterilizing, homogenizing the materials at 18-20MPa/65-70 deg.C, and sterilizing at 95 deg.C/300 s;

7. inoculating, fermenting, demulsifying, bottling and performing secondary fermentation, adding starter lactobacillus strain X1(10UC) into the sterilized milk cooled to 42-43 deg.C, stirring until the mixture is uniformly dispersed, stopping stirring and fermenting until the acidity is 70 ° T, and demulsifying and cooling to 18-22 deg.C; filling and transferring to a cold storage at 2-6 ℃ for secondary fermentation.

The invention has the beneficial effects that:

the invention relates to a flavored yoghurt which is prepared by taking fresh milk as a main raw material, simultaneously adding sweet potato powder, mixing quantitatively, homogenizing and sterilizing, inoculating, fermenting, demulsifying, filling and carrying out secondary fermentation.

The protein content of the product is more than or equal to 2.5 percent, the fat content is more than or equal to 2.7 percent, and the non-fat milk solid is more than or equal to 8.1 percent.

The characteristics of the contents of the final product of the invention are as follows:

(1) local characteristic resources are fully utilized, the advantages of the nutrition and the functional characteristics of the milk and the sweet potatoes are complemented, and efficient utilization is developed. The high-quality sweet potatoes which are local characteristic resources are developed as raw materials, milk protein has a complementary effect on essential amino acid in grains, insufficient milk carbohydrate is supplemented, and the functional characteristics of the sweet potatoes are reflected in the fermented milk. The invention utilizes modern nutriology, medicine and diet health theory, combines modern biotechnology and the like, and develops a novel dairy product which has nutrition, good taste and color and simultaneously endows the product with good functional characteristics.

(2) On the basis of enzymolysis, a functional dairy product is developed by utilizing the fermentation of a patent strain X1(10 UC).

The invention properly degrades starch in sweet potato, improves sweetness, reduces the addition of cane sugar, releases a plurality of functional active ingredients, and then combines the functional active ingredients with the functional active ingredients generated by probiotic fermentation to play respective advantages and complementary action.

(3) Improve the gel strength of the fermented milk and replace part of emulsion stabilizer.

The invention improves the gel strength of the fermented milk by gelatinizing starch in sweet potatoes and crosslinking protein, thereby replacing part of emulsion stabilizer and developing a natural and green novel fermented milk product.

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more readily understand the advantages and features of the present invention, and to clearly and unequivocally define the scope of the present invention.

Example 1

(1) Dissolving: mixing 2Kg stabilizer with 8Kg white sugar, dissolving with 300Kg milk solution at 65 deg.C, stirring for 20min, and mixing with the prepared sweet potato liquid for use. The stabilizer comprises the following components: glycerin monostearate, acetylated distarch phosphate, sodium tripolyphosphate, sodium alginate and gellan gum.

(2) Mixing and quantifying: mixing the rest milk with the solution dissolved in step (1), quantifying to 1000Kg, and cooling to below 10 deg.C before sterilization.

(3) Homogenizing and sterilizing: homogenizing at 18-20Mpa/65-70 deg.C, and sterilizing at 95 deg.C/300 s.

(4) Inoculation, fermentation, demulsification, filling and secondary fermentation: adding lactobacillus leaven X1(10UC) into the milk after sterilizing and cooling to 42-43 deg.C. Stirring until the mixture is uniformly dispersed, and stopping stirring and fermenting until the acidity is 70 DEG T. Then demulsifying and cooling to 18-22 ℃; filling and transferring to a cold storage at 2-6 ℃ for secondary fermentation.

Example 2

(1) Dissolving: mixing 3Kg stabilizer with 15Kg white sugar, dissolving with 300Kg milk solution at 65 deg.C, stirring for 20min, and mixing with the prepared sweet potato liquid for use. The stabilizer comprises the following components: glycerin monostearate, acetylated distarch phosphate, sodium tripolyphosphate, sodium alginate and gellan gum.

(2) Mixing and quantifying: mixing the rest milk with the solution dissolved in step (1), quantifying to 1000Kg, and cooling to below 10 deg.C before sterilization.

(3) Homogenizing and sterilizing: homogenizing at 18-20Mpa/65-70 deg.C, and sterilizing at 95 deg.C/300 s.

(4) Inoculation, fermentation, demulsification, filling and secondary fermentation: adding starter lactobacillus strain X1(10UC) into milk after sterilizing and cooling to 42-43 deg.C. Stirring until the mixture is uniformly dispersed, and stopping stirring and fermenting until the acidity is 70 DEG T. Then demulsifying and cooling to 18-22 ℃; filling and transferring to a cold storage at 2-6 ℃ for secondary fermentation.

Taste testing

The test purpose is as follows: and the organization professional quality personnel judge various sensory indexes of the product, so that the formula of the product is convenient to adjust.

And (3) test design: the overall feeling, milk flavor, consistency, freshness, sweetness, smoothness, refreshing, aftertaste, etc. of the product were evaluated separately.

Tasting mode: the method is carried out in a way of unregistering and scoring. 7 indexes of milk fragrance, thin consistency, sweetness, smoothness, tasty degree, aftertaste and overall feeling are tested. The full score is 10 points, and the higher the score is, the better the effect is. Statistical analysis of the tasting results, example 2 reflects well, with the following results:

1	milk flavor	9.6
			2	Consistency of thin	8.8
3	Sweetness level	8.2
			4	Degree of slipperiness of young children	8.9
5	Degree of refreshing	8.8
			6	Aftertaste	8.7
7	Feeling of unity	9.2

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.