阅读说明：本技术 一种高乳化性大豆蛋白的制备方法 (Preparation method of high-emulsibility soybean protein ) 是由 李杨 孙禹凡 张小影 孙远达 方琳 于 2019-10-22 设计创作，主要内容包括：本发明提供一种高乳化性大豆蛋白的制备方法,涉及蛋白粉加工技术领域。所述高乳化性大豆蛋白粉的生产方法,主要包括浸泡、研磨、浸提、震荡、酸沉、均质、酶解、糖基化、灭菌、冻干等步骤。本发明提高了大豆蛋白的乳化性、分散性及溶解性,使所得的大豆蛋白粉能被人体更高效的吸收,并且具有高稳定性,扩大了蛋白粉的应用范围,提升了经济效益。(The invention provides a preparation method of high-emulsibility soybean protein, and relates to the technical field of protein powder processing. The production method of the high-emulsibility soybean protein powder mainly comprises the steps of soaking, grinding, leaching, shaking, acid precipitation, homogenization, enzymolysis, glycosylation, sterilization, freeze-drying and the like. The invention improves the emulsibility, the dispersibility and the solubility of the soybean protein, ensures that the obtained soybean protein powder can be more efficiently absorbed by human bodies, has high stability, enlarges the application range of the protein powder and improves the economic benefit.)

1. A preparation method of high-emulsibility soybean protein is characterized by comprising the following steps:

(1) soaking soybeans in warm water for 3-4h, and grinding the soybeans in a grinder to obtain soybean slurry for later use;

(2) adjusting the pH value of the soybean slurry to 7.5-8.5, leaching for 40-50min, placing the slurry in an ultrasonic oscillator, and repeatedly extracting by ultrasonic oscillation to obtain oscillation liquid for later use;

(3) adding the shaking solution into a centrifuge, centrifuging at high speed for 10-15min to obtain supernatant, adjusting pH of the supernatant to 5.0, performing acid precipitation, adding into the centrifuge, and centrifuging to obtain precipitated protein;

(4) repeatedly washing the precipitated protein with deionized water for 3-4 times, adding 10 times by volume of deionized water into the precipitated protein, stirring uniformly, adjusting pH to be neutral, and homogenizing with a colloid mill for 2-3 times to obtain a homogeneous solution for later use;

(5) adding protease into the homogenized solution for enzymolysis at 50-55 deg.C for 3-4 hr to obtain enzymolysis solution;

(6) adding glucose into the enzymolysis solution, stirring, standing for 3-4 hr in sealed environment, sterilizing in an ultrasonic sterilizer, and freeze-drying the sterilized solution in a freeze-dryer to obtain high-emulsibility soybean protein powder.

2. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: the water temperature for soaking the soybeans in the step (1) is 30-35 ℃.

3. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: in the step (2), 0.8mol/L sodium hydroxide solution is adopted to adjust the pH value, the leaching temperature is 40-45 ℃, the oscillation frequency of the ultrasonic oscillator is 2-5 times, the ultrasonic power of each oscillation is 100-150W, the time is 10-15min, and the intermittent time of the oscillation is 20-25 min.

4. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: in the step (3), 0.5mol/L hydrochloric acid solution is adopted to adjust the pH value, the acid precipitation time is 20-30min, the high-speed centrifugation rotating speed is 4000r/min, and the centrifugation rotating speed after acid precipitation is 3200 r/min.

5. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: and (4) adjusting the pH value by adopting 0.2mol/L sodium hydroxide solution, wherein the clearance of the colloid mill is 0.1 mm.

6. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: the mass of the protease added in the step (5) is 5% of that of the protein precipitated in the step (3).

7. The method for preparing highly emulsifiable soybean protein as claimed in claim 1, wherein: the glucose added in the step (6) is 25 percent of the protein precipitated in the step (3), and the liquid needs to be kept at 65-70 ℃ when standing.

Technical Field

The invention relates to the technical field of protein powder processing, and particularly relates to a preparation method of high-emulsibility soybean protein.

Background

Protein is one of seven essential nutrients essential to human body. The human body takes in animal proteins as well as plant proteins through daily animal and plant foods. With the increasing health awareness and income level of people, the normal dietary approach can not meet the requirements on protein quality and can not meet the consumption requirements of people on healthy diet. Therefore, by processing animal food or plant food containing protein, high-purity protein raw material is extracted, and the protein raw material is widely used for production and processing in industries such as food, medicine, health care products and the like, and the protein is ingested in a healthier way through the product.

The emulsibility is the main functional characteristic of soybean protein, the protein has the characteristic structure of an emulsifier, namely an amphiphilic structure, and contains hydrophilic groups and lipophilic groups in protein molecules, so that the protein can be gathered on an oil-water interface, the interfacial tension is reduced, and the emulsion is formed. The soybean protein isolate can reduce the surface tension of water and oil, can reduce the surface tension of water and air, and is easy to form stable emulsion. After the emulsion is formed, the protein is aggregated on the surface of the oil drop to form a protective layer, which can effectively prevent aggregation of the oil drop and damage of the emulsified state and maintain the stability of the emulsion. However, the emulsifiability of soy protein products is different from that of sodium caseinate commonly used in industry, so it is necessary to modify soy protein to obtain soy protein products with high emulsifiability, and to expand the application range.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the preparation method of the high-emulsibility soybean protein, which improves the emulsibility, the dispersibility and the solubility of the soybean protein, enables the obtained soybean protein powder to be absorbed by human bodies more efficiently, has high stability, enlarges the application range and improves the economic benefit.

In order to achieve the above purpose, the technical scheme of the invention is realized by the following technical scheme:

a preparation method of high-emulsibility soybean protein comprises the following steps:

(1) soaking soybeans in warm water for 3-4h, and grinding the soybeans in a grinder to obtain soybean slurry for later use;

(2) adjusting the pH value of the soybean slurry to 7.5-8.5, leaching for 40-50min, placing the slurry in an ultrasonic oscillator, and repeatedly extracting by ultrasonic oscillation to obtain oscillation liquid for later use;

(3) adding the shaking solution into a centrifuge, centrifuging at high speed for 10-15min to obtain supernatant, adjusting pH of the supernatant to 5.0, performing acid precipitation, adding into the centrifuge, and centrifuging to obtain precipitated protein;

(4) repeatedly washing the precipitated protein with deionized water for 3-4 times, adding 10 times by volume of deionized water into the precipitated protein, stirring uniformly, adjusting pH to be neutral, and homogenizing with a colloid mill for 2-3 times to obtain a homogeneous solution for later use;

(5) adding protease into the homogenized solution for enzymolysis at 50-55 deg.C for 3-4 hr to obtain enzymolysis solution;

(6) adding glucose into the enzymolysis solution, stirring, standing for 3-4 hr in sealed environment, sterilizing in an ultrasonic sterilizer, and freeze-drying the sterilized solution in a freeze-dryer to obtain high-emulsibility soybean protein powder.

Preferably, the water temperature for soaking the soybeans in the step (1) is 30-35 ℃.

Preferably, in the step (2), 0.8mol/L sodium hydroxide solution is used to adjust the pH value, the leaching temperature is 40-45 ℃, the oscillation frequency of the ultrasonic oscillator is 2-5 times, the ultrasonic power of each oscillation is 100-150W, the time is 10-15min, and the oscillation intermission time is 20-25 min.

Preferably, in the step (3), 0.5mol/L hydrochloric acid solution is adopted to adjust the pH value, the acid precipitation time is 20-30min, the high-speed centrifugation rotating speed is 4000r/min, and the centrifugation rotating speed after acid precipitation is 3200 r/min.

Preferably, step (4) uses 0.2mol/L NaOH solution to adjust the pH value, and the gap of the colloid mill is 0.1 mm.

Preferably, the amount of protease added in step (5) is 5% of the amount of protein precipitated in step (3).

Preferably, the glucose added in step (6) is 25% of the protein precipitated in step (3), and the liquid is kept at 65-70 ℃ while standing.

The invention provides a preparation method of high-emulsibility soybean protein, which has the advantages that:

(1) the soybean is soaked in warm water at the temperature of 30-35 ℃, so that the soybean can be effectively soaked, the soybean milk yield is improved during grinding, and the beneficial components of the soybean are kept to the maximum extent.

(2) According to the invention, the soybean is soaked firstly and then repeatedly vibrated by the ultrasonic vibrator during leaching, so that the components such as protein in the soybean can be effectively separated, the content of the effective components in the supernatant obtained by later centrifugation is high, the utilization rate of the soybean is improved, and the protein molecules can be effectively and uniformly diffused by repeated vibration, so that the emulsibility and the solubility of the soybean protein in the later period are improved.

(3) According to the invention, after the soybean protein is subjected to enzymolysis, glucose is added to carry out glycosylation reaction, so that the emulsibility of the soybean protein powder obtained by the invention is further improved, and the absorption rate of a human body to the protein powder prepared by the invention is improved.

(4) The invention adopts a freeze-drying method to dry the protein to obtain the protein powder, can effectively improve the stability of the protein powder and enhance the solubility of the obtained protein powder.

Example 1:

a preparation method of high-emulsibility soybean protein comprises the following steps:

(1) soaking soybeans in warm water for 4h, and then adding the soybeans into a grinder for grinding to obtain soybean slurry for later use;

(2) adjusting the pH value of the soybean slurry to 7.5, leaching for 50min, placing the slurry in an ultrasonic oscillator, and repeatedly performing ultrasonic oscillation extraction to obtain oscillation liquid for later use;

(3) adding the shaking solution into a centrifuge, centrifuging at high speed for 10min to obtain supernatant, adjusting the pH of the supernatant to 5.0, performing acid precipitation, adding into the centrifuge, and centrifuging to obtain precipitated protein;

(4) repeatedly washing the precipitated protein with deionized water for 3 times, adding 10 volume parts of deionized water into the precipitated protein, stirring uniformly, adjusting the pH to be neutral, and homogenizing for 3 times by using a colloid mill to obtain a homogeneous solution for later use;

(5) adding protease into the homogenized solution for enzymolysis at 50-55 deg.C for 3-4 hr to obtain enzymolysis solution;

(6) adding glucose into the enzymolysis solution, stirring, standing for 3-4 hr in sealed environment, sterilizing in an ultrasonic sterilizer, and freeze-drying the sterilized solution in a freeze-dryer to obtain high-emulsibility soybean protein powder.

The water temperature for soaking the soybeans in the step (1) is 30-35 ℃; in the step (2), 0.8mol/L sodium hydroxide solution is adopted to adjust the pH value, the leaching temperature is 40-45 ℃, the oscillation frequency of an ultrasonic oscillator is 2 times, the ultrasonic power of each oscillation is 150W, the time is 10min, and the oscillation intermittence time is 20 min; in the step (3), 0.5mol/L hydrochloric acid solution is adopted to adjust the pH value, the acid precipitation time is 20-30min, the high-speed centrifugation rotating speed is 4000r/min, and the centrifugation rotating speed after acid precipitation is 3200 r/min; step (4) adjusting the pH value by adopting 0.2mol/L sodium hydroxide solution, wherein the clearance of the colloid mill is 0.1 mm; the mass of the protease added in the step (5) is 5% of that of the protein precipitated in the step (3); the glucose added in the step (6) is 25 percent of the protein precipitated in the step (3), and the liquid needs to be kept at 65-70 ℃ when standing.