阅读说明：本技术 一种合生元全豆豆腐的制备方法 (Preparation method of synbiotics whole bean curd ) 是由 邹强 刘雨蝶 赵江林 时小东 张驰松 于 2020-07-16 设计创作，主要内容包括：本发明提供一种合生元全豆豆腐的制备方法所述方法包括制备豆浆、制备益生菌包埋剂、包埋益生菌及将包埋好的益生菌加入到豆浆中制备得到合生元全豆豆腐的过程,该通过对益生菌进行微胶囊化保护处理,添加到豆腐中,开发得到一种高活性、高稳定性的合生元全豆豆腐,本发明还进一步提取豆渣中的可溶性膳食纤维用于豆腐制作,使得豆腐中含有可溶性纤维,更有利于身体健。(The invention provides a method for preparing synbiotics whole bean curd, which comprises the steps of preparing soybean milk, preparing a probiotic embedding agent, embedding probiotics and adding the embedded probiotics into the soybean milk to prepare the synbiotics whole bean curd.)

1. A preparation method of synbiotics whole bean curd is characterized by comprising the following steps: the method comprises the steps of preparing soybean milk, preparing a probiotic embedding agent, embedding probiotics and adding the embedded probiotics into the soybean milk to prepare the synbiotics whole-bean curd; the method comprises the following specific steps:

(1) preparing soybean milk: soaking and cleaning soybeans, adding water, performing pulping treatment by using a pulping machine, filtering supernatant after pulping, collecting filtrate and filter residues, wherein the filter residues are bean dregs, preserving the temperature of the collected filtrate at 70-80 ℃ for 20-30 minutes to obtain soybean milk, and refrigerating at 4 ℃; standby;

(2) preparing a probiotic embedding agent: adding sodium alginate powder into deionized water, and stirring to dissolve completely; then adding soluble dietary fiber and stirring to completely dissolve the soluble dietary fiber to obtain embedding agent solution for later use; wherein the soluble dietary fiber is prepared from the filter residue collected in the step (1);

(3) embedding probiotics: adding the concentrated probiotic suspension into an embedding agent solution, uniformly stirring, spraying into a CaCl2 solution, stirring and curing for 20-30 minutes, filtering by using filter paper to collect micelle, cleaning by using sterile water, and filtering for later use;

(4) preparing bean curd: heating the soybean milk prepared in the step (1) to 70-80 ℃, quickly adding the micelle prepared in the step (3), slowly adding a citric acid solution with the mass fraction of 1.2-1.8% into the soybean milk at 70-80 ℃, continuously stirring, stopping stirring when the pH of the soybean milk is 4.2-4.6, standing for 15-20 minutes, filtering, removing filtrate, and pressing and molding the intercepted milk mud in a mold to obtain the synbiotic whole bean curd.

2. The method for preparing synbiotics whole bean curd according to claim 1, wherein the method comprises the following steps: in step (1), soybeans are mixed according to a ratio of 1: 3-1: 4, soaking in water for 14-16 hours, then pouring out the soaking water, and washing the soaked soybeans with clean water for 2-3 times.

3. The method for preparing synbiotics whole bean curd according to claim 1, wherein the method comprises the following steps: the soluble dietary fiber in the step (2) is prepared by drying, crushing and sieving bean dregs, adding the bean dregs into clear water, adjusting the pH value to be 5.6-6.2 by using a hydrochloric acid solution, then putting the bean dregs into an autoclave, performing pressure pretreatment for 60-90 minutes at 120 ℃, then cooling to room temperature, adding a sodium carbonate solution, adjusting the pH value to be 11.8-12.5 by using a sodium hydroxide solution, filtering, precipitating the filtrate by using ethanol, filtering, and drying filter residues to obtain the soluble dietary fiber.

4. The method for preparing synbiotics whole bean curd according to claim 1, wherein the method comprises the following steps: in the step (2), the sodium alginate powder is prepared according to the weight ratio of 1: 50-1: 65 weight percent of the mixture is added into deionized water, and the mixture is fully stirred until the mixture is completely dissolved; then, mixing the components in a weight ratio of 1: 50-1: 65 adding soluble dietary fiber.

5. The method for preparing synbiotics whole bean curd according to claim 1, wherein in the step (3), the viable bacteria content of the concentrated probiotic suspension is 1 × 10¹⁰CFU/mL～1×10¹¹CFU/mL, as 1: 50-1: a volume ratio of 60 was taken into the embedding agent solution.

6. The method for preparing synbiotics whole bean curd according to claim 5, wherein the method comprises the following steps: and adding probiotic live bacteria to obtain embedding agent solution, conveying the embedding agent solution to an atomizer by using a peristaltic pump, and spraying the embedding agent solution into 1-1.5 mass percent CaCl2 solution under the pressure of 50-60 MPa.

7. The method for preparing synbiotics whole bean curd according to claim 1, wherein the method comprises the following steps: in the step (4) of preparing bean curd, the soybean milk prepared in the step (1) is heated to 70-80 ℃, and the soybean milk is prepared by mixing the soybean milk with the soybean milk according to the proportion of 1: 50-1: 60, quickly adding the micelle prepared in the step (3), slowly adding 1.2-1.8 mass percent of citric acid solution into the soybean milk at 70-80 ℃, continuously stirring at a stirring speed of 30-60 rpm, stopping adding the citric acid solution when the pH of the soybean milk is 4.2-4.6, completely curdling the soybean milk, stopping stirring, standing at 20-30 ℃ for 15-20 minutes, filtering by using double-layer Mazilin cotton cloth to remove filtrate, pressing and molding the intercepted milk mud in a mold, taking out the bean curd, placing the bean curd in cold water at 4-8 ℃, standing for 20-30 minutes, taking out the bean curd, removing surface water, and finishing to obtain the synbiotic whole bean curd.

8. The method for preparing synbiotics whole bean curd according to claim 3, wherein the method comprises the following steps: the soluble dietary fiber is prepared by drying bean dregs in a constant-temperature air-blast drying oven, drying for 30-40 hours at 50-55 ℃, crushing and sieving with a 20-mesh sieve, and then mixing the crushed dried bean dregs powder according to the weight ratio of 1: 8-1: 12, regulating the pH value to 5.6-6.2 by using a hydrochloric acid solution, pressurizing and pretreating in an autoclave at 120 ℃ for 60-90 minutes, cooling to room temperature, adding a sodium carbonate solution with the volume fraction of 4% -5% by 2-3 times, regulating the pH value to 11.8-12.5 by using a 1mol/L sodium hydroxide solution, carrying out constant temperature treatment at 80-90 ℃ for 80-90 minutes, cooling to room temperature, filtering, precipitating the filtrate by using ethanol with the volume of 4-5 times, filtering, drying the filter residue at 80-90 ℃ for 60-90 minutes, and collecting the dried soluble dietary fiber.

Technical Field

The invention belongs to the technical field of bean curd products, and particularly relates to a preparation method of synbiotics whole bean curd.

Background

The bean curd is a home-made dish and is popular among the elder people, and the probiotics are added into the bean curd, so that on one hand, the daily supplement of the probiotics can be realized, and the application range of the probiotics is expanded, on the other hand, the bean curd and the yoghourt are similar, and the bean curd is food which is mainly protein and stored at low temperature and can be used as a potential carrier of the probiotics. However, in the current invention, most probiotics are simply added into the bean curd, and the adverse environments of the bean curd during the production process (such as high temperature), the storage process (such as high humidity) and the eating process (such as gastric acid) are not considered, so that the probiotics are easily killed in quantity, and the efficacy of the probiotics is lost.

Application number CN201110435691 discloses a bean curd preparation method, which comprises the following steps: heating the soybean milk, adding probiotic liquid, stirring, standing for a certain time, and then performing compression molding to complete the preparation of the bean curd. The bean curd preparation method adopts the specific probiotics to replace bittern to prepare bean curd, and utilizes the characteristic that beneficial bacteria in the probiotics grow in the specific acidity environment to directly provide the environment for protein coagulation so as to replace the existing bittern with the protein gelling function. The production and the preparation of the bean curd are more efficient and the bean curd is safer to eat. In the patent with the application number of CN201110152690.9, a novel ecological bean curd and a preparation method thereof are provided, wherein the ecological bean curd is prepared by taking probiotic fermentation liquor as a coagulating point preparation and preparing soybean milk. The probiotic fermentation liquor is prepared by adding probiotic raw powder into soybean milk and fermenting. The novel ecological bean curd provided by the invention is milky in color, strong in elasticity, pure in bean flavor and good in taste, is rich in various essential trace elements of human bodies such as high-quality protein, iron, calcium, phosphorus, magnesium and the like, does not use substances such as gypsum, brine and the like, and is a pure natural, safer and healthier popular green nutritional food. In the technical scheme, the probiotic bean curd is prepared by directly adding probiotic bacteria for fermentation or by using a probiotic liquid method, and the operation inevitably leads to massive inactivation of the probiotic bacteria, so that the significance of the probiotic bean curd is lost.

Disclosure of Invention

The invention aims to solve the problems in the process of preparing bean curd containing probiotics in the prior art, and provides a preparation method of synbiotics whole bean curd.

In order to solve the technical problems, the invention is realized by the following technical scheme:

a method for preparing synbiotics whole bean curd comprises the steps of preparing soybean milk, preparing a probiotic embedding agent, embedding probiotics and adding the embedded probiotics into the soybean milk to prepare the synbiotics whole bean curd; the method comprises the following specific steps:

(1) preparing soybean milk: soaking and cleaning soybeans, adding water, performing pulping treatment by using a pulping machine, filtering supernatant after pulping, collecting filtrate and filter residues, wherein the filter residues are bean dregs, preserving the temperature of the collected filtrate at 70-80 ℃ for 20-30 minutes to obtain soybean milk, and refrigerating at 4 ℃; standby;

(2) preparing a probiotic embedding agent: adding sodium alginate powder into deionized water, and stirring to dissolve completely; then adding soluble dietary fiber and stirring to completely dissolve the soluble dietary fiber to obtain embedding agent solution for later use; wherein the soluble dietary fiber is prepared from the filter residue collected in the step (1);

(3) embedding probiotics: adding the concentrated probiotic suspension into an embedding agent solution, uniformly stirring, spraying into a CaCl2 solution, stirring and curing for 20-30 minutes, filtering by using filter paper to collect micelle, cleaning by using sterile water, and filtering for later use;

(4) preparing bean curd: heating the soybean milk prepared in the step (1) to 70-80 ℃, quickly adding the micelle prepared in the step (3), slowly adding a citric acid solution with the mass fraction of 1.2-1.8% into the soybean milk at 70-80 ℃, continuously stirring, stopping stirring when the pH of the soybean milk is 4.2-4.6, standing for 15-20 minutes, filtering, removing filtrate, and pressing and molding the intercepted milk mud in a mold to obtain the synbiotic whole bean curd.

Further, the present invention provides a process for treating soybeans, wherein in the step (1), soybeans are treated according to a ratio of 1: 3-1: 4, soaking in water for 14-16 hours, then pouring out the soaking water, and washing the soaked soybeans with clean water for 2-3 times.

The soluble dietary fiber in the step (2) is prepared by drying, crushing and sieving bean dregs, adding the bean dregs into clear water, adjusting the pH value to be 5.6-6.2 by using a hydrochloric acid solution, then putting the bean dregs into an autoclave, performing pressure pretreatment for 60-90 minutes at 120 ℃, then cooling to room temperature, adding a sodium carbonate solution, adjusting the pH value to be 11.8-12.5 by using a sodium hydroxide solution, filtering, precipitating the filtrate by using ethanol, filtering, and drying filter residues to obtain the soluble dietary fiber. Specifically, the soluble dietary fiber is prepared by drying bean dregs in a constant-temperature air-blast drying oven, drying for 30-40 hours at 50-55 ℃, crushing and sieving with a 20-mesh sieve, and then mixing the crushed dried bean dregs powder according to the weight ratio of 1: 8-1: 12, regulating the pH value to 5.6-6.2 by using a hydrochloric acid solution, pressurizing and pretreating in an autoclave at 120 ℃ for 60-90 minutes, cooling to room temperature, adding a sodium carbonate solution with the volume fraction of 4% -5% by 2-3 times, regulating the pH value to 11.8-12.5 by using a 1mol/L sodium hydroxide solution, carrying out constant temperature treatment for 80-90 minutes at 80-90 ℃, cooling to room temperature, filtering, precipitating the filtrate by using ethanol with the volume of 4-5 times, filtering, drying the filter residue at 80-90 ℃ for 60-90 minutes at constant temperature, and collecting the dried soluble dietary fiber.

In the step (2), the sodium alginate powder is prepared according to the weight ratio of 1: 50-1: 65 weight percent of the mixture is added into deionized water, and the mixture is fully stirred until the mixture is completely dissolved; then, mixing the components in a weight ratio of 1: 50-1: 65 adding soluble dietary fiber.

In the step (3), the viable bacteria content of the concentrated probiotic suspension is 1 × 10¹⁰CFU/mL～1×10¹¹CFU/mL, as 1: 50-1: a volume ratio of 60 was taken into the embedding agent solution. And adding probiotic live bacteria to obtain embedding agent solution, conveying the embedding agent solution to an atomizer by using a peristaltic pump, and spraying the embedding agent solution into 1-1.5 mass percent CaCl2 solution under the pressure of 50-60 MPa.

In the step (4) of preparing bean curd, the soybean milk prepared in the step (1) is heated to 70-80 ℃, and the soybean milk is prepared by mixing the soybean milk with the soybean milk according to the proportion of 1: 50-1: 60, quickly adding the micelle prepared in the step (3), slowly adding 1.2-1.8 mass percent of citric acid solution into the soybean milk at 70-80 ℃, continuously stirring at a stirring speed of 30-60 rpm, stopping adding the citric acid solution when the pH of the soybean milk is 4.2-4.6, completely curdling the soybean milk, stopping stirring, standing at 20-30 ℃ for 15-20 minutes, filtering by using double-layer Mazilin cotton cloth to remove filtrate, pressing and molding the intercepted milk mud in a mold, taking out the bean curd, placing the bean curd in cold water at 4-8 ℃, standing for 20-30 minutes, taking out the bean curd, removing surface water, and finishing to obtain the synbiotic whole bean curd.

The invention has the following beneficial effects:

1. in the curdling process of the bean curd, high-temperature treatment is involved, and high temperature can cause the death of lactobacillus casei, the invention utilizes microcapsule technology to embed the lactobacillus casei in sodium alginate microcapsules, and can resist the destructive effect of high temperature on the lactobacillus casei; the survival rate of probiotics added into the bean curd is improved, and the survival rate of lactobacillus casei embedded by the sodium alginate is higher in the low-temperature storage process of the bean curd.

2. According to the invention, the bean dregs after pulping are comprehensively utilized for the first time, and the soluble dietary fiber in the bean dregs is extracted, but the method of the invention adopts crushing, hydrochloric acid extraction and alkali liquor dissolution, and then the fiber powder precipitated by ethanol is soluble dietary fiber, which is a prebiotic used in probiotic embedding, and the survival rate under the physical or chemical loss in the bean curd preparation process at the later stage is further ensured under the action of the prebiotic and the soluble dietary fiber; in gastric juice of a human body, the survival rate of lactobacillus casei is largely dead under a high-acid environment, and sodium alginate has higher stability under the acid environment, can effectively resist the damage of acid liquor to lactobacillus casei, and can also play a synergistic protection role with soluble dietary fibers.

3. The invention adopts the bean dregs as the raw material for extracting the dietary fiber, realizes the comprehensive utilization of the by-product bean dregs and prepares the whole bean curd.

Detailed Description