阅读说明：本技术 一种高蛋白豆酸奶及其制备方法 (High-protein bean yoghourt and preparation method thereof ) 是由 王磊 莫蓓红 刘振民 徐致远 于 2020-11-19 设计创作，主要内容包括：本发明涉及乳制品加工领域,特别是涉及一种高蛋白豆酸奶及其制备方法。本发明提供一种高蛋白豆酸奶的制备方法,包括：1)超滤处理；2)杀菌处理；3)闪蒸脱气处理；4)发酵处理。本发明所提供的高蛋白豆酸奶的制备方法采用预先膜滤浓缩方法,精确调节浓缩比,采用低温过膜技术,最大程度降低了产品的脂肪哈败味道,同时也避免了由于后浓缩造成pH较低而无法利用副产物的情况。所得产品口感醇厚,细腻顺滑,豆香味足,同时由于高粘度的特性无需添加稳定剂,在保质期期间能够维持良好的稳定性,给予消费者全新的味蕾体验,具有良好的产业化前景。(The invention relates to the field of dairy product processing, in particular to high-protein bean yoghourt and a preparation method thereof. The invention provides a preparation method of high-protein bean yoghourt, which comprises the following steps: 1) performing ultrafiltration treatment; 2) sterilizing; 3) carrying out flash evaporation and degassing treatment; 4) and (5) fermentation treatment. The preparation method of the high-protein bean yoghourt adopts a pre-membrane filtration concentration method, accurately adjusts the concentration ratio, adopts a low-temperature membrane technology, reduces the fat rancidity taste of the product to the maximum extent, and simultaneously avoids the condition that the pH value is lower and the by-product cannot be utilized due to post-concentration. The obtained product has mellow taste, is fine and smooth, has sufficient bean fragrance, can maintain good stability during the shelf life due to the characteristic of high viscosity without adding a stabilizer, gives brand new taste bud experience to consumers, and has good industrialization prospect.)

1. A method for preparing high protein bean yoghourt comprises the following steps:

1) performing ultrafiltration treatment on the soybean milk base material to provide trapped fluid;

2) sterilizing the trapped fluid provided in the step 1) to provide a sterilized material;

3) carrying out flash evaporation degassing treatment on the material subjected to the sterilization treatment and provided by the step 2) to provide a flash evaporation degassing treated material;

4) fermenting the material subjected to flash evaporation and degassing treatment provided by the step 3) to provide a fermentation product, wherein the pH of the fermentation product is 4.6-4.8.

2. The method for preparing high-protein soy yogurt according to claim 1, wherein in the step 1), the protein content of the soy milk base is 2.5-4.5 wt%, preferably 2.9-3.5 wt%, more preferably 3.0-3.1 wt%, and the fat content of the soy milk base is 0.7-1.5 wt%, preferably 0.8-1.3 wt%, more preferably 0.9-1.1 wt%.

3. The method of preparing high protein soy yogurt according to claim 1, wherein the soy milk base material in step 1) comprises soy flour and water.

4. The method for preparing the high-protein bean yogurt according to claim 3, wherein in the step 1), the protein content of the bean flour is 35-45 wt%, preferably 40-45 wt%, more preferably 40-41 wt%, and the fat content of the bean flour is 10-15 wt%, preferably 10-13 wt%, more preferably 11.5-12.5 wt%.

5. The method for preparing the high-protein bean yoghourt according to claim 1, wherein in the step 1), the temperature of the ultrafiltration membrane is 20-30 ℃, the preferred temperature is 20-25 ℃, the more preferred temperature is 20-23 ℃, and the ultrafiltration pressure of the ultrafiltration membrane is 1-6 bar, the preferred pressure is 2-5 bar, and the more preferred pressure is 2-4 bar.

6. The method for preparing high-protein bean yogurt according to claim 1, wherein in the step 1), the filtration concentration ratio of the ultrafiltration treatment is 2.3-3.

7. The method for preparing the high-protein bean yogurt according to claim 1, wherein in the step 1), the retentate obtained by the ultrafiltration treatment contains 5.75-13.5 wt% of protein and 1.6-4.5 wt% of fat.

8. The preparation method of the high-protein bean yogurt according to claim 1, wherein in the step 2), the sterilization treatment is ultra-high temperature sterilization treatment, the treatment temperature of the ultra-high temperature sterilization treatment is 135-145 ℃, preferably 135-140 ℃, more preferably 135-137 ℃, and the treatment time of the high temperature sterilization treatment is 0.1-1 s, preferably 0.1-0.5 s, more preferably 0.1-0.3 s;

and/or, in the step 3), the flash degassing treatment is carried out under the pressure condition of-0.3 to-0.8 bar, preferably under the pressure condition of-0.4 to-0.7 bar, and more preferably under the pressure condition of-0.6 to-0.7 bar.

9. The method for preparing the high-protein bean yoghourt according to the claim 1, wherein in the step 4), the strain used in the fermentation treatment is selected from one or more of streptococcus thermophilus and lactobacillus bulgaricus, and the fermentation temperature is 40-45 ℃;

and/or in the step 4), the pH value of the fermentation product is 4.7-4.8, preferably 4.75-4.8.

10. A high-protein bean yogurt, which is prepared by the preparation method of the high-protein bean yogurt as claimed in any one of claims 1 to 9.

Technical Field

The invention relates to the field of dairy product processing, in particular to high-protein bean yoghourt and a preparation method thereof.

Background

With the global dairy market becoming saturated, consumers are gradually pursuing more new flavors, new product categories. Meanwhile, consumers are more advocating natural, nutritional and environment-friendly products and pay attention to self health management. Dairy products processed from oat, coconut, soybean and other plant raw materials gradually come into the field of view of the public abroad. Statistically, the global vegetable protein market in 2019 is estimated to be 185 billion yuan, and is increased with a compound annual growth rate of 14%.

The soybean milk has the habit of drinking soybean products such as soybean milk and the like from ancient times in China, the flavor acceptance of soybeans is higher in various plant-based dairy raw materials, soybean isoflavone is rich in soybean protein, cholesterol is reduced, cardiovascular and cerebrovascular health is promoted, and dietary fiber can promote intestinal absorption. However, in the existing domestic and foreign markets, high-protein bean yogurt products are still fresh, and a small amount of existing high-protein bean yogurt products also have certain problems, for example, the traditional thermal separation method of high-protein products is easy to generate fat rancidity in a plant-based system, and the high-protein products are also easy to generate powder feeling and the like.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention aims to provide a high protein soy yogurt and a method for preparing the same, which solve the problems of the prior art.

In order to achieve the above and other related objects, the present invention provides, in one aspect, a method for preparing a high protein soy yogurt, comprising:

1) performing ultrafiltration treatment on the soybean milk base material to provide trapped fluid;

2) sterilizing the trapped fluid provided in the step 1) to provide a sterilized material;

3) carrying out flash evaporation degassing treatment on the material subjected to the sterilization treatment and provided by the step 2) to provide a flash evaporation degassing treated material;

4) fermenting the material subjected to flash evaporation and degassing treatment provided by the step 3) to provide a fermentation product, wherein the pH of the fermentation product is 4.6-4.8.

In some embodiments of the present invention, in the step 1), the protein content of the soybean milk base is 2.5 to 4.5 wt%, preferably 2.9 to 3.5 wt%, and more preferably 3.0 to 3.1 wt%, and the fat content of the soybean milk base is 0.7 to 1.5 wt%, preferably 0.8 to 1.3 wt%, and more preferably 0.9 to 1.1 wt%.

In some embodiments of the present invention, in the step 1), the raw materials of the soybean milk base include soybean flour and water.

In some embodiments of the present invention, in step 1), the protein content of the soybean flour is 35 to 45 wt%, preferably 40 to 45 wt%, more preferably 40 to 41 wt%, and the fat content of the soybean flour is 10 to 15 wt%, preferably 10 to 13 wt%, more preferably 11.5 to 12.5 wt%.

In some embodiments of the invention, in the step 1), the temperature of the ultrafiltration membrane is 20-30 ℃, preferably 20-25 ℃, and more preferably 20-23 ℃, and the ultrafiltration pressure of the ultrafiltration is 1-6 bar, preferably 2-5 bar, and more preferably 2-4 bar.

In some embodiments of the present invention, in the step 1), the filtration concentration ratio of the ultrafiltration treatment is 2.3 to 3.

In some embodiments of the invention, in the step 1), the retentate obtained by the ultrafiltration treatment contains 5.75-13.5 wt% of protein and 1.6-4.5 wt% of fat.

In some embodiments of the invention, in the step 2), the sterilization treatment is ultra-high temperature sterilization treatment, the treatment temperature of the ultra-high temperature sterilization treatment is 135-145 ℃, preferably 135-140 ℃, and more preferably 135-137 ℃, and the treatment time of the high temperature sterilization treatment is 0.1-1 s, preferably 0.1-0.5 s, and more preferably 0.1-0.3 s;

and/or, in the step 3), the flash degassing treatment is carried out under the pressure condition of-0.3 to-0.8 bar, preferably under the pressure condition of-0.4 to-0.7 bar, and more preferably under the pressure condition of-0.6 to-0.7 bar.

In some embodiments of the invention, in the step 4), the bacterial species used in the fermentation treatment is selected from one or more of streptococcus thermophilus and lactobacillus bulgaricus, and the fermentation temperature is 40-45 ℃;

and/or in the step 4), the pH value of the fermentation product is 4.7-4.8, preferably 4.75-4.8.

The invention also provides high-protein bean yoghourt which is prepared by the preparation method of the high-protein bean yoghourt.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments, and other advantages and effects of the present invention will be apparent to those skilled in the art from the disclosure of the present specification.

The inventor of the invention provides a preparation method of high-protein bean yoghourt, and the preparation method obtains the high-protein bean yoghourt by a method of membrane filtration concentration in advance through a large amount of practical research. The obtained product has good stability and good taste in the shelf life, and the invention is completed on the basis.

The invention provides a preparation method of high-protein bean yoghourt, which comprises the following steps:

1) performing ultrafiltration treatment on the soybean milk base material to provide trapped fluid;

2) sterilizing the trapped fluid provided in the step 1) to provide a sterilized material;

3) carrying out flash evaporation degassing treatment on the material subjected to the sterilization treatment and provided by the step 2) to provide a flash evaporation degassing treated material;

4) fermenting the material subjected to flash evaporation and degassing treatment provided by the step 3) to provide a fermentation product, wherein the pH of the fermentation product is 4.6-4.8.

The preparation method of the high-protein bean yoghourt provided by the invention can comprise the following steps: the soy milk base is subjected to ultrafiltration to provide a retentate. In this application, ultrafiltration is generally a membrane separation technique, which refers to a process of passing a material under pressure through the surface of a membrane, allowing a solvent (e.g., water) and small solutes smaller than the pores of the membrane to permeate the membrane to form a purified solution (filtrate), and trapping solutes larger than the pores of the membrane and discharging the solutes together with the material to form a concentrated solution (retentate). The soybean milk base material is ultrafiltered, the concentration ratio can be accurately adjusted, and no acidic soybean whey is produced.

In the above-mentioned preparation method, the soybean milk base is generally required to have a suitable protein content and/or fat content. The proper protein content can ensure that the protein content is not too high to generate powder feeling and astringent feeling after concentration, and the proper fat content can ensure that the finished product does not generate greasy feeling after concentration. For example, the protein content of the soybean milk base may be 2.5 to 4.5 wt%, 2.5 to 2.7 wt%, 2.7 to 2.9 wt%, 2.9 to 3 wt%, 3 to 3.1 wt%, 3.1 to 3.2 wt%, 3.2 to 3.3 wt%, 3.3 to 3.4 wt%, 3.4 to 3.5 wt%, 3.5 to 3.7 wt%, 3.7 to 4 wt%, or 4 to 4.5 wt%, preferably may be 2.9 to 3.5 wt%, more preferably may be 3.0 to 3.1 wt%. For another example, the fat content of the soy milk base may be 0.7 to 1.5 wt%, 0.7 to 0.8 wt%, 0.8 to 0.9 wt%, 0.9 to 1 wt%, 1 to 1.1 wt%, 1.1 to 1.2 wt%, 1.2 to 1.3 wt%, 1.3 to 1.4 wt%, or 1.4 to 1.5 wt%, preferably may be 0.8 to 1.3 wt%, more preferably may be 0.9 to 1.1 wt%.

Of the above preparation methods, suitable methods for providing a soy milk base should be known to those skilled in the art. For example, the soybean milk base may be prepared by mixing soybean powder (a powdery food obtained by baking and pulverizing soybeans) and water, and dissolving the soybean powder in an appropriate amount of water. For another example, the protein content of the soybean powder used may be 35 to 45 wt%, 35 to 37 wt%, 37 to 39 wt%, 39 to 40 wt%, 40 to 41 wt%, 41 to 42 wt%, 42 to 43 wt%, 43 to 44 wt%, or 44 to 45 wt%, preferably 40 to 45 wt%, and more preferably 40 to 41 wt%. For another example, the fat content of the soybean flour used may be 10 to 15 wt%, 10 to 11 wt%, 11 to 11.5 wt%, 11.5 to 12 wt%, 12 to 12.5 wt%, 12.5 to 13 wt%, 13 to 14 wt%, or 14 to 15 wt%, preferably 10 to 13 wt%, and more preferably 11.5 to 12.5 wt%.

In the preparation method, the filtration concentration ratio of the ultrafiltration treatment can be usually 2.3-3, 2.3-2.4, 2.4-2.5, 2.5-2.6, 2.6-2.7, 2.7-2.8, 2.8-2.9, or 2.9-3. The filtration concentration ratio is the ratio of the mass percent protein content in the retentate to the mass percent protein content in the feed (i.e., soy milk base). At this concentration ratio, the final product has a high protein content and no powdery or astringent feeling (e.g., no powdery or astringent feeling). For example, the retentate obtained by the ultrafiltration treatment may have a protein content of 5.75 to 13.5 wt%, 5.75 to 6 wt%, 6 to 7 wt%, 7 to 8 wt%, 8 to 9 wt%, 9 to 10 wt%, 10 to 11 wt%, 11 to 12 wt%, 12 to 13 wt%, or 13 to 13.5 wt%. For another example, the retentate obtained from the ultrafiltration treatment may have a fat content of 1.6 to 4.5 wt%, 1.6 to 2 wt%, 2 to 2.5 wt%, 2.5 to 3 wt%, 3 to 3.5 wt%, 3.5 to 4 wt%, or 4 to 4.5 wt%. In general, the treatment conditions of the ultrafiltration treatment can be appropriately adjusted by those skilled in the art according to the filtration concentration ratio required for the ultrafiltration treatment. For example, the ultrafiltration pressure of the ultrafiltration treatment may be 1 to 6bar, 1 to 2bar, 2 to 3bar, 3 to 4bar, 4 to 5bar, or 5 to 6bar, preferably 2 to 5bar, and more preferably 2 to 4 bar. For another example, in the ultrafiltration treatment, the cut-off molecular weight of the ultrafiltration membrane used may be 3000 to 10000, 3000 to 4000, 4000 to 5000, 5000 to 6000, 6000 to 7000, 7000 to 8000, 8000 to 9000, or 9000 to 10000, preferably 5000 to 8000, more preferably 5000 to 7000.

In the above preparation method, the ultrafiltration treatment is usually carried out at a relatively low temperature to reduce the heat load on the fat in the system and prevent rancidity of the fat. For example, the temperature of the ultrafiltration membrane may be 20 to 30 ℃, 20 to 21 ℃, 21 to 22 ℃, 22 to 23 ℃, 23 to 24 ℃, 24 to 25 ℃, 25 to 26 ℃, 26 to 27 ℃, 27 to 28 ℃, 28 to 29 ℃, or 29 to 30 ℃, preferably 20 to 25 ℃, and more preferably 20 to 23 ℃.

The preparation method of the high-protein bean yoghourt provided by the invention can also comprise the following steps: sterilizing the trapped fluid provided in the step 1) to provide a sterilized material. In this application, sterilization generally refers to a treatment process for heat-treating a material at a suitable temperature and duration to kill germs in the material. Before fermentation treatment, materials are generally required to be sterilized, so that the influence of microorganisms in the raw materials on subsequent fermentation and other steps is avoided.

In the above preparation method, the sterilization treatment may be usually ultra-high temperature sterilization treatment. Suitable ultra-high temperature sterilization treatment conditions should be known to those skilled in the art. For example, steam immersion sterilization or steam injection sterilization may be employed. For another example, the treatment temperature of the ultra-high temperature sterilization treatment may be 135 to 145 ℃, preferably 135 to 140 ℃, and more preferably 135 to 137 ℃. For another example, the treatment time of the ultra-high temperature sterilization treatment may be 0.1 to 1 second, preferably 0.1 to 0.5 second, and more preferably 0.1 to 0.3 second.

In the preparation method, before the trapped fluid provided in the step 1) is subjected to sterilization treatment, the trapped fluid provided in the step 1) can be preheated, so that the aim of preheating is to ensure that the temperature of the material can be raised to the required sterilization temperature, and avoid coking caused by instant rise of the temperature to influence the heat transfer efficiency. For example, the trapped fluid provided in step 1) may be preheated to 75-95 ℃, 75-80 ℃, 80-85 ℃, 85-90 ℃, or 90-95 ℃ before the trapped fluid provided in step 1) is sterilized.

The preparation method of the high-protein bean yoghourt provided by the invention can also comprise the following steps: carrying out flash evaporation degassing treatment on the material subjected to the sterilization treatment and provided by the step 2) to provide a flash evaporation degassing treated material. In this application, flash degassing generally refers to a process in which a fluid (e.g., a liquid) in a relatively high-pressure environment is introduced into a relatively low-pressure environment, and then the fluid is rapidly vaporized due to a sudden drop in pressure, thereby performing gas-liquid separation. Flash evaporation degassing can mainly remove peculiar smell in the system and evaporate more water generated by ultra-high temperature sterilization.

In the above-mentioned production method, the conditions of the flash degassing treatment can be suitably adjusted by those skilled in the art. For example, the flash degassing treatment may be carried out under a pressure condition of-0.3 to-0.8 bar, -0.3 to-0.4 bar, -0.4 to-0.5 bar, -0.5 to-0.6 bar, -0.6 to-0.7 bar, or-0.7 to-0.8 bar, preferably under a pressure condition of-0.4 to-0.7 bar, and more preferably under a pressure condition of-0.6 to-0.7 bar. For another example, the inlet temperature of the flash degassing treatment is usually matched with the treatment temperature of the ultra-high temperature sterilization treatment, and may be 135-145 ℃, 135-140 ℃, or 140-145 ℃. For another example, the outlet temperature of the flash degassing treatment may be 55 to 70 ℃, 55 to 60 ℃, 60 to 65 ℃, or 65 to 70 ℃. And (3) pre-cooling the flash-evaporated and degassed material at a proper outlet temperature for flash evaporation and degassing treatment, wherein the pre-cooling aims to cool the sterilized material to a temperature required for homogenization.

The preparation method of the high-protein bean yoghourt provided by the invention can also comprise the following steps: subjecting the material subjected to flash degassing provided in step 3) to a fermentation treatment to provide a fermentation product. In the present application, a fermentation process generally refers to a process of preparing a microbial cell itself, or a direct metabolite or a secondary metabolite, by virtue of the living activity of a microorganism under aerobic or anaerobic conditions. After the materials are subjected to proper fermentation treatment, the high-protein bean yoghourt can be provided.

In the above production method, the fermentation treatment may generally include: inoculating, fermenting and the like. In fermentation processes it is often necessary to inoculate the material with suitable bacterial species. For example, the applicable bacterial species may be one or a combination of more of Streptococcus thermophilus (Streptococcus thermophilus), Lactobacillus bulgaricus (Lactobacillus bulgaricus), and the like. As another example, the inoculum size of the bacterial species in the material may be 1X 10⁶～8×10⁶cfu/mL、1×10⁶～2×10⁶cfu/mL、2×10⁶～4×10⁶cfu/mL、4×10⁶～6×10⁶cfu/mL, or 6X 10⁶～8×10⁶cfu/mL, the inoculation ratio of the streptococcus thermophilus to the lactobacillus bulgaricus can be 1-3: 1, 1-1.2: 1, 1.2-1.4: 1, 1.4-1.6: 1, 1.6-1.8: 1, 1.8-2: 1, 2-2.2: 1, 2.2-2.4: 1, 2.4-2.6: 1, 2.6-2.8: 1, or 2.8-3: 1. After the materials are inoculated, the fermentation system can be fermented, and the specific fermentation temperature can be 40-45 ℃, 40-41 ℃, 41-42 ℃, 42-43 ℃, 43-44 ℃ or 44-45 ℃. In the fermentation process, the fermentation focus can be determined according to the pH value of the fermentation system, for example, when the pH of the fermentation system is 4.6 to 4.8, 4.6 to 4.65, 4.65 to 4.7, 4.7 to 4.75, or 4.75 to 4.8, preferably 4.7 to 4.8, more preferably 4.75 to 4.8, the fermentation can be terminated, and the fermentation system can be cooled (for example, the fermentation system can be cooled)Cooling the cylinder to 20-25 ℃, smoothing by a smoothing pump when the cylinder is turned, wherein the opening degree of the smoothing pump is 10-30%, preferably 20-30%, more preferably 25-30%).

The second aspect of the invention provides high-protein bean yoghourt which is prepared by the preparation method of the high-protein bean yoghourt provided by the first aspect of the invention.

The preparation method of the high-protein bean yoghourt adopts a pre-membrane filtration concentration method, accurately adjusts the concentration ratio, adopts a low-temperature membrane technology, reduces the fat rancidity taste of the product to the maximum extent, and simultaneously avoids the condition that the pH value is lower and the by-product cannot be utilized due to post-concentration. The obtained product has mellow taste, is fine and smooth, has sufficient bean fragrance, can maintain good stability during the shelf life due to the characteristic of high viscosity without adding a stabilizer, gives brand new taste bud experience to consumers, and has good industrialization prospect.

The invention of the present application is further illustrated by the following examples, which are not intended to limit the scope of the present application.

The specific information of the materials used in the examples is as follows:

bean flour: purchased from shanghai Xin melt food materials, ltd;

strain: purchased from dupont china ltd.

Example 1

(1) 100g of bean flour with the protein content of 40% and the fat content of 12.5% is taken, 1250mL of water is added to ensure that the protein content of the soybean milk base material is 3.0% and the fat content is 0.9%, and the materials are mixed for 30min at the temperature of 40 ℃;

(2) concentrating the soybean milk base material at 4bar and 20 deg.C with a cut-off molecular weight of 5000, and passing through ultrafiltration membrane to obtain a cut-off solution with a concentration ratio of 2.5, wherein the cut-off solution has a protein content of 7.3% and a fat content of 2.3%;

(3) preheating the trapped material to 80 deg.C, sterilizing at 137 deg.C for 0.1s, flash evaporating at-0.6 bar, degassing, cooling to 60 deg.C, aseptically homogenizing at 40MPa, and cooling to 42 deg.C;

(4) the above materials were inoculated and fermented (using DuPont vege series Streptococcus thermophilus and Lactobacillus bulgaricus,the ratio is 2:1, the inoculation amount is 1 × 10⁶cfu/mL, fermentation temperature 42 ℃), turning over the cylinder, smoothing by a smoothing pump when the fermentation is carried out until the pH is 4.6 (opening degree of the smoothing pump is 10%), cooling to 20 ℃, and ending the fermentation;

(5) filling the above materials at 20 deg.C, and refrigerating to obtain the product.

Example 2

(1) 100g of soybean powder with 41 percent of protein content and 11.5 percent of fat content is taken, 950mL of water is added to ensure that the protein content of the soybean milk base material is 3.9 percent and the fat content is 1.1 percent, and the materials are mixed for 15min at the temperature of 60 ℃;

(2) subjecting the above materials to ultrafiltration membrane at 25 deg.C and 2.4 bar to obtain retentate with molecular weight of 5000 and protein content of 9.4% and fat content of 2.6%;

(3) preheating the trapped material to 85 deg.C, sterilizing at 135 deg.C for 0.3s, flash evaporating at-0.3 bar, degassing, cooling to 65 deg.C, sterilizing at 60MPa, homogenizing, and cooling to 44 deg.C;

(4) inoculating the above materials to ferment (using DuPont vege series Streptococcus thermophilus and Lactobacillus bulgaricus at ratio of 2:1, and inoculating amount of 8 × 10⁶cfu/mL, fermentation temperature 44 ℃), turning over the cylinder, smoothing by a smoothing pump when the fermentation is carried out until the pH is 4.7 (opening degree of the smoothing pump is 20%), cooling to 25 ℃, and ending the fermentation;

(5) filling the above materials at 25 deg.C, and refrigerating to obtain the product.

Example 3

(1) Mixing 100g of bean flour with 35% of protein content and 10% of fat content with 1300mL of water to make the protein content of the soybean milk base material 2.5% and the fat content 0.71%, and mixing for 20min at 50 ℃;

(2) subjecting the above materials to ultrafiltration membrane at 23 deg.C and 1bar to cut-off molecular weight of 5000, concentrating to obtain cut-off solution with concentration ratio of 2.3, protein content of 5.75% and fat content of 1.63%;

(3) preheating the trapped material to 90 deg.C, sterilizing at 140 deg.C for 1s, flash-evaporating at-0.7 bar, degassing, cooling to 65 deg.C, aseptically homogenizing at 80MPa, and cooling to 43 deg.C;

(4) inoculating the above materials to ferment (using DuPont vege series Streptococcus thermophilus and Bulgaria)Lactobacillus in the ratio of 2:1, the inoculation amount of 2 × 10⁶cfu/mL, fermentation temperature 43 ℃), turning over the cylinder when fermentation is carried out until pH is 4.75, smoothing by a smoothing pump (opening of the smoothing pump is 25%), cooling to 23 ℃, and ending fermentation;

(5) filling the above materials at 23 deg.C, and refrigerating to obtain the product.

Example 4

(1) 100g of bean flour with 45 percent of protein content and 15 percent of fat content is taken, 900mL of water is added to ensure that the protein content of the soybean milk base material is 4.5 percent and the fat content is 1.5 percent, and the materials are mixed for 25min at the temperature of 45 ℃;

(2) subjecting the above materials to ultrafiltration membrane at 30 deg.C and 6bar to cut-off molecular weight of 10000 to obtain cut-off solution with concentration ratio of 3, protein content of the cut-off solution 13.5% and fat content of 4.5%;

(3) preheating the trapped material to 90 deg.C, sterilizing at 145 deg.C for 0.1s, flash-evaporating at-0.8 bar, degassing, cooling to 65 deg.C, aseptically homogenizing at 100MPa, and cooling to 44 deg.C;

(4) inoculating the above materials to ferment (using DuPont vege series Streptococcus thermophilus and Lactobacillus bulgaricus at ratio of 2:1, and inoculating amount of 3 × 10⁶cfu/mL, fermentation temperature 44 ℃), turning over the jar when the fermentation is carried out until the pH is 4.8, smoothing by a smoothing pump (opening degree of the smoothing pump is 30%), cooling to 25 ℃, and finishing the fermentation;

(5) filling the above materials at 25 deg.C, and refrigerating to obtain the product.

Example 5

(1) Taking 100g of bean flour with 40% of protein content and 13% of fat content, adding 1200mL of water to ensure that the protein content of the soybean milk base material is 3% and the fat content is 1%, and mixing for 30min at 55 ℃;

(2) subjecting the above materials to ultrafiltration membrane at a cut-off molecular weight of 10000 at 5bar and 20 deg.C to obtain a cut-off solution with a concentration ratio of 2.8, wherein the cut-off solution contains 8.4% of protein and 2.8% of fat;

(3) preheating the trapped material to 80 deg.C, sterilizing at 140 deg.C for 0.5s, flash-evaporating at-0.4 bar, degassing, cooling to 65 deg.C, aseptically homogenizing at 50MPa, and cooling to 44 deg.C;

(4) inoculating the above materials to ferment (using DuPont vege series Streptococcus thermophilus andlactobacillus bulgaricus at a ratio of 2:1 and an inoculum size of 4 × 10⁶cfu/mL, fermentation temperature 44 ℃), turning over the jar when the fermentation is carried out until the pH is 4.7, smoothing by a smoothing pump (opening degree of the smoothing pump is 15%), cooling to 25 ℃, and finishing the fermentation;

(5) filling the above materials at 25 deg.C, and refrigerating to obtain the product.

Example 6

(1) Taking 100g of bean flour with 35% of protein content and 13% of fat content, adding 900mL of water to ensure that the protein content of the soybean milk base material is 3.5% and the fat content is 1.3%, and mixing for 15min at 40 ℃;

(2) subjecting the above materials to ultrafiltration membrane at a cut-off molecular weight of 8000 and 4bar and 22 deg.C to obtain a cut-off solution with a concentration ratio of 2.5, protein content of the cut-off solution of 8.6% and fat content of 3.3%;

(3) preheating the trapped material to 80 deg.C, sterilizing at 137 deg.C for 0.5s, flash-evaporating at-0.8 bar, degassing, cooling to 65 deg.C, aseptically homogenizing at 100MPa, and cooling to 43 deg.C;

(4) inoculating the above materials to ferment (using DuPont vege series Streptococcus thermophilus and Lactobacillus bulgaricus at ratio of 2:1, and inoculating amount of 5 × 10⁶cfu/mL), when the fermentation is carried out until the pH value is 4.8, turning over the cylinder, smoothing by a smoothing pump (the opening degree of the smoothing pump is 30 percent), and cooling to 23 ℃ to finish the fermentation;

(5) filling the above materials at 23 deg.C, and refrigerating to obtain the product.

Comparative example 1

The method is the same as the embodiment 1, except that the concentration method is changed into fermentation and then concentration is carried out by a centrifugal machine, the centrifugal temperature is 42-44 ℃, heavy phase is taken after centrifugation, and then the heavy phase is cooled to 20-25 ℃.

20 sensory evaluators (10 men and women, and both industry research and development experts) are selected to taste the soybean milk sample, and sensory evaluation is carried out on three aspects of smell, taste and mouthfeel, the evaluation table referred to by the sensory evaluation refers to table 1, and the specific results of the sensory evaluation refer to table 2.

TABLE 1 sensory evaluation chart

TABLE 2 scoring results

As can be seen from the results in table 2, in comparative example 1, the fat is easily degraded during the thermal concentration process to generate rancid taste due to the high content of unsaturated fatty acids in the raw material, which affects the taste.

In conclusion, the present invention effectively overcomes various disadvantages of the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.