Preparation method of fermented soybean milk with strong gel property

Abstract

The invention discloses a preparation method of fermented soybean milk with strong gel property, and belongs to the technical field of food fermentation. In order to effectively improve the gel strength of the fermented soybean milk, the invention provides a preparation method of the fermented soybean milk, which mainly comprises the following steps: cleaning soybeans, peeling, degerming and soaking; treating by a jet cavitation machine, separating slurry and slag, and performing flash evaporation; soybean milk is taken, dissolved, blended, subjected to ultrasonic treatment, homogenized, sterilized and cooled; and fermenting the lactobacillus casei fermenting agent and the prebiotics mixture, refrigerating and performing after-ripening. The fermented soybean milk obtained by the invention is fermented by whole plants, has no beany flavor, bitterness and unpleasant odor, is fine and smooth in mouth feel and strong in gel property, and has rich fermented soybean fragrance; the product is rich in nutrition, free of animal raw materials, low in production cost and good in flavor.

Description

Technical Field

[0001] The invention belongs to the technical field of food fermentation, and in particular relates to a method for preparing strong gel fermented soybean milk. Background Art

[0002] Ultrasound is a motion that consists of mechanical sound waves from molecules and oscillates in a propagation medium. Ultrasound has a very high frequency, about 20kHz, and is divided into two categories (i.e., low-intensity and high-intensity waves). Ultrasound reduces the time required for cheese ripening by releasing intracellular enzymes, accelerating the decomposition of protein structures, and enhancing texture, sensory properties, and nutritional properties. It has been observed that the application of high-intensity ultrasound can reduce the size of fat globules in yogurt production, increase viscosity, reduce syneresis, increase gel strength, and accelerate fermentation. It also helps to form a firmer yogurt through the denaturation of whey proteins, the splitting of casein micelles, and the reorganization of protein parts. However, the application of ultrasound technology in the field of fermented soy milk is not mature enough. Soy milk is a high-quality plant protein beverage with soybeans as the main raw materials. It is widely popular among the public because it contains proteins and unsaturated fatty acids that are easily absorbed by the human body, and it is rich in mineral salts and does not contain cholesterol. With the continuous improvement of the public's demand for healthy consumption, protein drinks fermented by plant sources and probiotics are becoming more and more popular. However, the problems of severe whey precipitation, poor gelation, and unstable state during the fermentation of soy milk have always hindered the development of the fermented soy milk industry. Summary of the invention

[0003] The purpose of the present invention is to effectively improve the gel property of fermented soybean milk. In order to solve the above technical problems, the present invention provides a preparation method of fermented soybean milk with strong gel property. The fermented soybean milk is obtained after inoculating a mixture of a lactobacillus casei fermentation agent and prebiotics in soybean milk for fermentation, and is obtained after fermentation after ultrasonic treatment, wherein the ultrasonic condition is 20KHz, the ultrasonic power is 400-600W, and the ultrasonic time is 15-20min.

[0004] The present invention also provides a method for preparing the fermented soymilk, and the preparation method is as follows:

[0005] (1) taking 100 g of soybeans, cleaning the soybeans, peeling and removing the embryos, then adding 0.01% to 0.03% by mass of calcium chloride to 800 ml of water at a temperature of 65° C. to mix well, and then soaking the peeled and embryo-free soybeans in the water for 10 to 20 minutes;

[0006] (2) treating the soybeans soaked in water obtained in step (1) by using a jet cavitation machine, separating the pulp and residue, flash evaporating the soybean milk, and adding 3.5% to 4.0% by mass of sucrose to the soybean milk;

[0007] (3) soy milk is ultrasonicated, homogenized, sterilized and cooled to obtain a soy milk mixture;

[0008] (4) adding a mixture of 2.6%-3.5% by mass of a Lactobacillus casei fermentation agent and 1.8%-2.4% by mass of a prebiotic to the soymilk mixture, with a fermentation temperature of 33° C.-37° C., a fermentation time of 8 h-12 h, and a fermentation termination acidity of 42-45° T.

[0009] It is further defined that the dehulling in step (1) means that the soybean hull content is ≤ 1% of the total soybean hull volume fraction, and the degermination means that the volume of the soybean embryo is ≤ 0.2% of the total soybean volume fraction.

[0010] It is further defined that the treatment conditions using a jet cavitation machine in step (2) are a cavitation pressure of 180 MPa-250 MPa and a treatment time of 20 min-30 min.

[0011] It is further defined that the ultrasonic conditions in step (3) are 20 KHz, ultrasonic power is 400-600 W, ultrasonic time is 15-20 min, homogenization pressure is 40 MPa-50 MPa, and homogenization time is 3 min-5 min.

[0012] It is further defined that the sterilization in step (3) is steam direct injection dry heat sterilization, the steam is dry heat saturated steam, the sterilization temperature is 145°C-147°C, and the time is 5s-7s.

[0013] It is further defined that the prebiotic in step (4) is inulin.

[0014] Beneficial effects: The fermented soybean milk provided by the present invention is fermented by whole plants, has no beany smell, bitter taste and bad smell, has strong gelling property, high viscosity, delicate taste and strong fermented bean fragrance; it is rich in nutrition, has no animal raw materials, has low production cost and good flavor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the process diagram of strong gel fermented soy milk. Specific embodiments

[0016] Lactobacillus casei starter culture was purchased commercially from Shandong Zhongke Jiayi Biotechnology Co., Ltd.

[0017] The soybeans selected in the present invention are Longken soybeans, which are purchased commercially.

[0018] Example 1.

[0019] A method for preparing strong gel fermented soybean milk, the specific steps are as follows:

[0020] (1) taking 100 g of soybeans, cleaning the soybeans, peeling and removing the embryos, then adding 0.02% by mass of calcium chloride to 800 ml of water at a temperature of 65° C. and mixing, and then soaking the peeled and embryo-free soybeans in water for 15 minutes, wherein peeling means that the soybean peel content is ≤ 1% of the total soybean peel volume fraction, and the embryo-free means that the volume of the soybean embryo is ≤ 0.2% of the total soybean volume fraction;

[0021] (2) treating the soybeans soaked in water obtained in step (1) by a jet cavitation machine, wherein the treatment conditions of the jet cavitation machine are a cavitation pressure of 200 MPa and a treatment time of 25 min, and then separating the pulp and residue, flash evaporating the soybean milk, and adding 3.5% by mass of sucrose to the soybean milk;

[0022] (3) The soy milk is subjected to ultrasound, homogenization, sterilization and cooling to obtain a soy milk mixture, the ultrasound condition is 20 kHz, the ultrasound power is 500 W, the ultrasound time is 15 min, the homogenization pressure is 40 MPa, the homogenization time is 5 min, the sterilization is steam direct injection dry heat sterilization, the steam is dry heat saturated steam, the sterilization temperature is 145° C., and the time is 7 s;

[0023] (4) adding a mixture of 3.0% by mass of Lactobacillus casei fermentation agent and 2.0% by mass of prebiotics to the soymilk mixture, wherein the prebiotics are inulin, the fermentation temperature is 35° C., the fermentation time is 10 h, and the fermentation termination acidity is 42° T.

[0024] Example 2.

[0025] A method for preparing strong gel fermented soybean milk, the specific steps are as follows:

[0026] (1) 100 g of soybeans are taken, the soybeans are cleaned, the hulls are peeled and the embryos are removed, and then 0.03% by mass of calcium chloride is added to 800 ml of water at a temperature of 70° C. and mixed evenly, and the peeled and embryo-free soybeans are placed in the water and soaked for 17 minutes, wherein the peeling means that the soybean hull content is ≤ 1% of the total soybean hull volume fraction, and the embryo removal means that the volume of the soybean embryo is ≤ 0.2% of the total soybean volume fraction;

[0027] (2) treating the soybeans soaked in water obtained in step (1) by a jet cavitation machine, wherein the treatment conditions of the jet cavitation machine are a cavitation pressure of 250 MPa and a treatment time of 20 min, and then separating the pulp and residue, flash evaporating the soybean milk, and adding 4.0% by mass of sucrose to the soybean milk;

[0028] (3) The soy milk is subjected to ultrasound, homogenization, sterilization and cooling to obtain a soy milk mixture, the ultrasound condition is 20 kHz, the ultrasound power is 600 W, the ultrasound time is 15 min, the homogenization pressure is 50 MPa, the homogenization time is 3 min, the sterilization is steam direct injection dry heat sterilization, the steam is dry heat saturated steam, the sterilization temperature is 147° C., and the time is 5 s;

[0029] (4) adding a mixture of 3.5% by mass of Lactobacillus casei fermentation agent and 2.4% by mass of prebiotics to the soymilk mixture, wherein the prebiotics are inulin, the fermentation temperature is 37° C., the fermentation time is 8 h, and the fermentation termination acidity is 45° T.

[0030] The following experiment was used to verify the experimental effect: Example 2 was used to verify the experimental effect:

[0031] 1. The indicators are determined as follows:

[0032] 1. Sensory evaluation

[0033] Ten people anonymously test the wine under bright light, looking straight ahead and evaluating the wine in terms of color, flavor, and texture. The total score of the three indicators is 100. The higher the score, the better the effect. The tasting results are statistically analyzed.

[0034] 2. Gel strength and water holding capacity

[0035] The obtained fermented soy milk was cooled to 4°C and allowed to stand for 8 hours, then the fermented sour soy milk was taken out and its gel strength and water holding capacity were measured.

[0036] 2. Results Analysis

[0037] 1. Sensory evaluation

[0038] Table 1 Sensory evaluation results

[0039]

[0040] 2. Gel strength and water holding capacity

[0041] Table 2 Gel strength and water holding capacity test results

[0042]

[0043] As shown in Table 2, the gel strength and water holding capacity of fermented soy milk can be significantly improved by jet cavitation and ultrasonic treatment of fermented soy milk.

Claims

1. A method for preparing highly gelatinous fermented soybean milk, It is characterized in that The fermented soymilk is obtained by inoculating a mixture of Lactobacillus casei and prebiotics into soymilk for fermentation.

2. The fermented soymilk according to claim 1 is obtained by fermentation after ultrasonic treatment, the ultrasonic conditions are 20KHz, the ultrasonic power is 400-600W, and the ultrasonic time is 15-20min.

3. The method for preparing the fermented soybean milk according to claim 1, It is characterized in that The preparation method is as follows: (1) taking 100 g of soybeans, cleaning the soybeans, peeling and removing the embryos, then adding 0.01% to 0.03% by mass of calcium chloride to 800 ml of water at a temperature of 65° C. to mix well, and then soaking the peeled and embryo-free soybeans in the water for 10 to 20 minutes; (2) treating the soybeans soaked in water obtained in step (1) by using a jet cavitation machine, separating the pulp and residue, flash evaporating the soybean milk, and adding 3.5% to 4.0% by mass of sucrose to the soybean milk; (3) soy milk is ultrasonicated, homogenized, sterilized and cooled to obtain a soy milk mixture; (4) adding a mixture of 2.6%-3.5% by mass of a Lactobacillus casei fermentation agent and 1.8%-2.4% by mass of a prebiotic to the soymilk mixture, with a fermentation temperature of 33° C.-37° C., a fermentation time of 8 h-12 h, and a fermentation termination acidity of 42-45° T.

4. The preparation method according to claim 3, It is characterized in that The dehulling in step (1) means that the soybean hull content is ≤ 1% of the total soybean hull volume fraction, and the degermination means that the volume of the soybean embryo is ≤ 0.2% of the total soybean volume fraction.

5. The preparation method according to claim 3, It is characterized in that The treatment conditions of the jet cavitation machine in step (2) are as follows: the cavitation pressure is 180MPa-250MPa, and the treatment time is 20min-30min.

6. The preparation method according to claim 3, It is characterized in that The ultrasonic conditions in step (3) are 20KHz, ultrasonic power is 400-600W, ultrasonic time is 15-20min, homogenization pressure is 40MPa-50MPa, and homogenization time is 3min-5min.

7. The preparation method according to claim 3, It is characterized in that The sterilization in step (3) is steam direct spray dry heat sterilization, the steam is dry heat saturated steam, the sterilization temperature is 145°C-147°C, and the time is 5s-7s.

8. The preparation method according to claim 3, It is characterized in that The prebiotic in step (4) is inulin.

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