Vegetable protein peptide fermentation product as well as preparation method and application thereof

Abstract

The invention relates to the technical field of plant extraction, in particular to a plant protein peptide fermentation product and a preparation method and application thereof. The preparation method comprises the following steps: treating the plants; preparing vegetable protein nanoparticles; activating the strain; and preparing the vegetable protein peptide fermentation product. Glycyrrhiza uralensis, momordica grosvenori, purslane, wolfberry, citron, rose and reed rhizome are mixed and then crushed twice, the first crushing is to release saponin in the glycyrrhiza uralensis through physical extrusion, the saponin has the effect of a surfactant, then a NaCl solution is added, the saponin and the NaCl solution are combined, osmotic pressure inside and outside plant cell walls is firstly pressurized, the osmotic pressure inside and outside the plant cell walls is increased, the osmotic pressure inside and outside the plant cell walls is increased, and the osmotic pressure inside and outside the plant cell walls is increased; the plant cell wall toughness is reduced, the saponin can destroy the plant cell wall, and the combination of the plant cell wall toughness and the saponin improves the destructiveness on the plant cell wall, thereby promoting the release of protein in the plant cell, and improving the extraction efficiency of plant protein and the yield of the plant protein peptide fermentation product.

Description

Technical Field

[0001] The present invention relates to the technical field of plant extraction, and in particular to a plant protein peptide fermentation product and a preparation method and application thereof. Background Art

[0002] Plant protein fermentation is a product prepared by microbial fermentation technology. It can be used to produce functional foods, such as as a drug carrier to improve the targeting and efficacy of drugs and reduce side effects, or as a high-quality animal feed to improve the digestion, absorption and growth performance of animals. It can also be added to meal replacement powders, beverages, health foods, or added to skin care products to provide moisturizing, repair and anti-aging effects. Among them, soybeans, peanuts, peas and other plants are often used as animal feed and drug carriers. These plants have high protein content, are easy to extract, and have low irritation. However, relatively speaking, the extracted soybean protein and peanut protein have simple functions and are suitable for drug carriers, but when added to health foods or skin care products, they play a smaller role. Traditional Chinese medicine ingredients such as monk fruit, purslane, wolfberry, and reed root, as traditional Chinese medicinal materials, have antioxidant, immunity-enhancing and anti-inflammatory effects. The protein content in these plants is not as good as that in soybeans and peanuts, but the protein extracted from them has multiple functions. Therefore, it is necessary to extract the plant protein from these substances and prepare them into plant protein fermentation.

[0003] However, the prior art generally uses the method of extracting soy protein to extract these Chinese medicinal plants. Since the content of soy protein in soybeans is relatively high, even without treatment, it still has a good plant protein yield. However, for Chinese medicinal plants, the yield of protein extraction and preparation of fermentation products is not high. Therefore, the present invention provides a plant protein peptide fermentation product and a preparation method and application thereof to solve the above problems. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention aims to provide a plant protein peptide fermentation product and a preparation method and application thereof.

[0005] A method for preparing a plant protein peptide fermentation product comprises the following steps:

[0006] S1: Treating plants

[0007] Grind licorice, monk fruit, purslane, wolfberry, citron, rose and reed root in a grinder to obtain a mixed slurry, mix the mixed slurry with a NaCl solution to obtain a treated slurry, mix n-hexane with the treated slurry to obtain an intermediate product I, mix the intermediate product I with n-hexane, then heat and evaporate to remove the solvent, filter, and dry the filter residue to obtain a mixed treated powder;

[0008] S2: Preparation of plant protein nanoparticles

[0009] The mixed processed powder is mixed with distilled water, shaken and centrifuged to remove precipitates, the pH value is adjusted, and the precipitates are separated after standing to obtain extracted plant protein powder, the extracted plant protein powder is dispersed in distilled water to obtain a plant protein solution, an ultrasonic cell pulverizer titanium probe is inserted under the liquid surface of the plant protein solution, ultrasonically shaken, and the product is freeze-dried to obtain plant protein nanoparticles;

[0010] S3: Bacteria Activation

[0011] Prepare a potato glucose liquid culture medium, sterilize and cool it, and then use an inoculation needle to pick a loop from a test tube to inoculate Aspergillus oryzae for culture, so as to obtain activated Aspergillus oryzae in the culture medium, prepare a liquid culture medium, and use an inoculation needle to pick a loop from a test tube to inoculate Bifidobacterium bifidum for culture, so as to obtain activated Bifidobacterium bifidum;

[0012] S4: Preparation of plant protein peptide fermentation

[0013] After the activation of the strain is completed, the bran and distilled water are mixed and put into a culture bottle. After sterilization and cooling, the bacterial solution of activated Aspergillus oryzae is respectively drawn with a sterile pipette and added to the culture bottle for cultivation to obtain a primary fermentation product. The plant protein nanoparticles are weighed, distilled water is added, sterilized, and the primary fermentation product and activated Bifidobacterium bifidum bacterial solution are added for cultivation to obtain a plant protein peptide fermentation product.

[0014] Furthermore, step S1 processes the plants, including the following steps:

[0015] S1.1: 40-80 parts by weight of licorice, 20-50 parts by weight of monk fruit, 15-30 parts by weight of purslane, 10-30 parts by weight of wolfberry, 12-18 parts by weight of citron, 15-30 parts by weight of rose and 20-25 parts by weight of reed root are put into a grinder and crushed for 5-10 minutes to obtain a mixed slurry, and then the mixed slurry is mixed with NaCl solution at a solid-liquid ratio of 1: (8-10) g / L, and finely crushed and beaten for 30-50 minutes to obtain a treated slurry;

[0016] S1.2: n-hexane and the treated slurry are mixed at a solid-liquid ratio of 1:(5-8) g / L, and placed in a 65-85°C water bath oscillator at a speed of 150-200 r / min for 10-20 min to obtain intermediate product I. The intermediate product I is mixed with n-hexane at a solid-liquid ratio of 1:(2-3) g / L, and then oscillated in a 40-55°C water bath for 5-10 min, then heated to 70-75°C and maintained for 5-10 min to evaporate the solvent, filtered, and the filter residue is dried in an oven at 60-80°C for 3-4 h to obtain a mixed treated powder.

[0017] Furthermore, step S2 of preparing plant protein nanoparticles comprises the following steps:

[0018] S2.1: Take the mixed processed powder and mix it evenly with 6-8 times volume of distilled water, adjust the pH to 10-11 with 1-2 mol / L NaOH solution, place it in a 50-60℃ water bath oscillator at 100-150r / min for 20-30min, centrifuge to remove the precipitate, add HCl solution to adjust the pH value of the supernatant to 4-4.5, let it stand for 20-25min, separate the precipitate, wash the precipitate with water 2-3 times and air-dry it to obtain the extracted plant protein powder;

[0019] S2.2: Disperse the extracted plant protein powder in distilled water at a solid-liquid ratio of 1:(5-10) g / mL, adjust the pH to 8-8.5 to obtain a plant protein solution, insert the titanium probe of an ultrasonic cell crusher 1-2 cm below the liquid surface of the plant protein solution, control the temperature to 0-4°C in an ice bath, perform ultrasonic oscillation for 20-30 minutes, and freeze-dry the product to obtain plant protein nanoparticles.

[0020] Furthermore, in step S2.2, the ultrasonic oscillation power is 400-500W.

[0021] Furthermore, step S3, bacterial activation, comprises the following steps:

[0022] S3.1: Prepare 100-200 mL of potato glucose liquid medium with 200-220 g / L of potato powder and 20-25 g / L of glucose, sterilize and cool, inoculate Aspergillus oryzae with an inoculation needle from a test tube, and culture on a shaker at 30-34°C and 160-180 r / min for 72-76 h to obtain activated Aspergillus oryzae in the medium;

[0023] S3.2: Prepare 100-200 mL of liquid culture medium with 5-10 g / L broth, 3-5 g / L yeast powder, 5-10 g / L glucose, 1-3 g / L starch, 3-5 g / L sodium acetate and 0.5-0.8 g / L L-cysteine ​​hydrochloride. In a sterile operating table, use an inoculation needle to pick a loop from a test tube to inoculate Bifidobacterium bifidum. Incubate at 36-37° C. in a constant temperature incubator for 24-26 hours to obtain activated Bifidobacterium bifidum.

[0024] Furthermore, the Bifidobacterium bifidum in step S3.2 is specifically Bifidobacterium bifidum TMC3115.

[0025] Furthermore, step S4 prepares the plant protein peptide fermentation product, comprising the following steps:

[0026] S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1: (2-3), and 30-40 mL is taken and put into a culture bottle. After sterilization and cooling, 2-3 mL of the activated Aspergillus oryzae bacterial solution is respectively taken with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly, and then cultured in a constant temperature incubator at 36-37° C. for 24-26 hours to obtain a primary fermentation product;

[0027] S4.2: Weigh 1-1.5 parts by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 121-125°C for 15-20 min, let stand and cool to 24-26°C, then add 3-4 parts by mass of primary fermentation product and 2-3mL of activated Bifidobacterium bifidum culture solution, seal with cotton plug, and culture on a shaker at 30-34°C, 160-180r / min for 72-76h to obtain plant protein peptide fermentation product.

[0028] A plant protein peptide fermentation product is prepared by the above-mentioned method for preparing a plant protein peptide fermentation product.

[0029] An application of a plant protein peptide fermentation product, and an application of the plant protein peptide fermentation product prepared by the above-mentioned method for preparing a plant protein peptide fermentation product in health food.

[0030] Compared with the prior art, the present invention has at least the following beneficial effects:

[0031] 1. The present invention mixes licorice, momordica grosvenori, purslane, wolfberry, citron, rose and reed root and then performs two crushing treatments. The first crushing is to release saponin in the licorice by physical extrusion. Saponin has the function of a surfactant. Then, a NaCl solution is added. The saponin is combined with the NaCl solution. First, the osmotic pressure inside and outside the plant cell wall is pressurized, so that the toughness of the plant cell wall decreases. The saponin can destroy the plant cell wall. The combination of the two increases the destructiveness of the plant cell wall, thereby promoting the release of protein in the plant cells, thereby improving the extraction efficiency of plant protein and the yield of plant protein peptide fermentation products.

[0032] 2. The present invention ferments the extracted plant protein nanoparticles through asynchronous fermentation, and the fermentation of Aspergillus oryzae and the fermentation of Bifidobacterium bifidum are carried out step by step. Aspergillus oryzae can decompose anti-nutritional factors such as phytic acid, tannin and trypsin inhibitor in plant protein, and converts complex macromolecules in plant protein into smaller peptides and amino acids during the fermentation process. In addition, Aspergillus oryzae also produces polysaccharide substances that are beneficial to the reproduction of Bifidobacterium bifidum during the fermentation process. After the fermentation of Aspergillus oryzae, the small molecule peptides and amino acids are further metabolized and converted into short-chain fatty acids through the fermentation of Bifidobacterium bifidum, thereby improving the bioavailability of plant protein, greatly enriching the nutritional components of plant protein fermentation products, and improving the nutritional value.

[0033] 3. The present invention prepares plant protein nanoparticles from plant protein powder. The nanoparticles have a larger specific surface area and can provide more reaction sites, thereby accelerating the fermentation process. In addition, the nanoparticles have better dispersibility in the solution and can be more evenly distributed in the fermentation medium. After combining with bran, the nanoparticles can be evenly distributed on the surface of the bran. The bran serves as a substrate for the implantation and reproduction of microorganisms. The plant protein nanoparticles evenly distributed on the surface stimulate the microorganisms to reproduce in large quantities and convert the plant protein, thereby improving the substrate utilization, thereby improving the fermentation efficiency and the yield of the fermentation product. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0035] Figure 1 The present invention is a flow chart of a method for preparing a plant protein peptide fermentation product used in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0037] Embodiment 1:

[0038] A method for preparing a plant protein peptide fermentation product, such as Figure 1 As shown, the following steps are included:

[0039] S1: Treating plants

[0040] S1.1: 40 parts by weight of licorice, 20 parts by weight of monk fruit, 15 parts by weight of purslane, 10 parts by weight of wolfberry, 12 parts by weight of citron, 15 parts by weight of rose and 20 parts by weight of reed root were put into a grinder and crushed for 5 minutes to obtain a mixed slurry, and then the mixed slurry was mixed with NaCl solution at a solid-liquid ratio of 1:10 g / L, and finely crushed and beaten for 30 minutes to obtain a treated slurry;

[0041] S1.2: n-hexane and the treated slurry were mixed at a solid-liquid ratio of 1:5 g / L, and placed in an 85°C water bath oscillator at a speed of 200 r / min for 20 min to obtain intermediate product I. The intermediate product I was mixed with n-hexane at a solid-liquid ratio of 1:2 g / L, and then oscillated in a 55°C water bath for 10 min, then heated to 75°C and maintained for 5 min to evaporate the solvent, filtered, and the filter residue was dried in an oven at 80°C for 4 h to obtain a mixed treated powder.

[0042] S2: Preparation of plant protein nanoparticles

[0043] S2.1: Take the mixed processed powder and mix it evenly with 6 times the volume of distilled water, adjust the pH to 11 with 1 mol / L NaOH solution, place it in a 50℃ water bath oscillator at 150r / min for 30min, centrifuge to remove the precipitate, add HCl solution to adjust the pH value of the supernatant to 4.5, let it stand for 25min, separate the precipitate, wash the precipitate with water 3 times and air-dry it to obtain the extracted plant protein powder;

[0044] S2.2: Disperse the extracted plant protein powder in distilled water at a solid-liquid ratio of 1:5 g / mL, adjust the pH to 8 to obtain a plant protein solution, insert the titanium probe of an ultrasonic cell crusher into the plant protein solution 1 cm below the liquid surface, control the temperature to 4°C in an ice bath, perform ultrasonic oscillation for 20 minutes, and the ultrasonic oscillation power is 400 W. After freeze-drying the product, plant protein nanoparticles are obtained.

[0045] S3: Bacteria Activation

[0046] S3.1: Prepare 100 mL of potato glucose liquid medium with 200 g / L potato powder and 20 g / L glucose, sterilize and cool, inoculate Aspergillus oryzae with a needle from a test tube, and culture on a shaker at 30°C and 160 r / min for 72 h to obtain activated Aspergillus oryzae in the medium;

[0047] S3.2: Prepare 100 mL of liquid culture medium with 5 g / L broth, 3 g / L yeast powder, 5 g / L glucose, 1 g / L starch, 3 g / L sodium acetate and 0.5 g / L L-cysteine ​​hydrochloride. Use an inoculation needle to pick a loop from the test tube and inoculate Bifidobacterium bifidum TMC3115 on a sterile operating table. Incubate the mixture at 36°C in a constant temperature incubator for 24 hours to obtain activated Bifidobacterium bifidum.

[0048] S4: Preparation of plant protein peptide fermentation

[0049] S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1:2, and 30 mL is taken and put into a culture bottle. After sterilization and cooling, 2 mL of the activated Aspergillus oryzae bacterial solution is respectively taken with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly, and then cultured at 36°C in a constant temperature incubator for 24 hours to obtain a primary fermentation product;

[0050] S4.2: Weigh 1 part by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 121°C for 15 min, let stand and cool to 24°C, then add 3 parts by mass of primary fermentation product and 2 mL of activated Bifidobacterium bifidum bacterial solution, seal with cotton plug, and culture on a shaker at 30°C and 160 r / min for 72 h to obtain plant protein peptide fermentation product.

[0051] Embodiment 2:

[0052] A method for preparing a plant protein peptide fermentation product, such as Figure 1 As shown, the following steps are included:

[0053] S1: Treating plants

[0054] S1.1: 80 parts by weight of licorice, 50 parts by weight of monk fruit, 30 parts by weight of purslane, 30 parts by weight of wolfberry, 18 parts by weight of citron, 30 parts by weight of rose and 25 parts by weight of reed root were put into a grinder and crushed for 5 minutes to obtain a mixed slurry, and then the mixed slurry was mixed with NaCl solution at a solid-liquid ratio of 1:8 g / L, and finely crushed and beaten for 30 minutes to obtain a treated slurry;

[0055] S1.2: n-hexane and the treated slurry were mixed at a solid-liquid ratio of 1:8 g / L, and placed in an 85°C water bath oscillator at a speed of 200 r / min for 20 min to obtain intermediate product I. The intermediate product I was mixed with n-hexane at a solid-liquid ratio of 1:3 g / L, and then oscillated in a 55°C water bath for 10 min, then heated to 75°C and maintained for 5 min to evaporate the solvent, filtered, and the filter residue was dried in an oven at 80°C for 4 h to obtain a mixed treated powder.

[0056] S2: Preparation of plant protein nanoparticles

[0057] S2.1: Take the mixed processed powder and mix it evenly with 8 times the volume of distilled water, adjust the pH to 11 with 1 mol / L NaOH solution, place it in a 50°C water bath oscillator and oscillate at 150 r / min for 30 min, centrifuge to remove the precipitate, then add HCl solution to adjust the pH value of the supernatant to 4.5, let it stand for 25 min, separate the precipitate, wash the precipitate with water 3 times and air-dry it to obtain the extracted plant protein powder;

[0058] S2.2: Disperse the extracted plant protein powder in distilled water at a solid-liquid ratio of 1:10 g / mL, adjust the pH to 8 to obtain a plant protein solution, insert the titanium probe of an ultrasonic cell crusher into the plant protein solution 1 cm below the liquid surface, control the temperature to 4°C in an ice bath, perform ultrasonic oscillation for 20 minutes, and the ultrasonic oscillation power is 400 W. After freeze-drying the product, plant protein nanoparticles are obtained.

[0059] S3: Bacteria Activation

[0060] S3.1: Prepare 100 mL of potato glucose liquid medium with 220 g / L potato powder and 25 g / L glucose, sterilize and cool, inoculate Aspergillus oryzae with an inoculation needle from a test tube, and culture on a shaker at 30°C and 160 r / min for 72 h to obtain activated Aspergillus oryzae in the medium;

[0061] S3.2: Prepare 100 mL of liquid culture medium with 10 g / L broth, 5 g / L yeast powder, 10 g / L glucose, 3 g / L starch, 5 g / L sodium acetate and 0.8 g / L L-cysteine ​​hydrochloride. Use an inoculation needle to pick a loop from the test tube and inoculate Bifidobacterium bifidum TMC3115 on a sterile operating table. Incubate the mixture at 36°C in a constant temperature incubator for 24 hours to obtain activated Bifidobacterium bifidum.

[0062] S4: Preparation of plant protein peptide fermentation

[0063] S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1:3, and 30 mL is taken and put into a culture bottle. After sterilization and cooling, 2 mL of the activated Aspergillus oryzae bacterial solution is respectively taken with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly, and then cultured at 36°C in a constant temperature incubator for 24 hours to obtain a primary fermentation product;

[0064] S4.2: Weigh 1.5 parts by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 121°C for 15 minutes, let stand and cool to 24°C, then add 4 parts by mass of primary fermentation product and 2 mL of activated Bifidobacterium bifidum bacterial solution, seal with cotton plug, and culture on a shaker at 30°C and 160 r / min for 72 hours to obtain plant protein peptide fermentation product.

[0065] Embodiment 3:

[0066] A method for preparing a plant protein peptide fermentation product, such as Figure 1 As shown, the following steps are included:

[0067] S1: Treating plants

[0068] S1.1: 40 parts by weight of licorice, 20 parts by weight of monk fruit, 15 parts by weight of purslane, 10 parts by weight of wolfberry, 12 parts by weight of citron, 15 parts by weight of rose and 20 parts by weight of reed root were put into a grinder and crushed for 10 minutes to obtain a mixed slurry, and then the mixed slurry was mixed with NaCl solution at a solid-liquid ratio of 1:10 g / L, and finely crushed and beaten for 50 minutes to obtain a treated slurry;

[0069] S1.2: n-hexane and the treated slurry were mixed at a solid-liquid ratio of 1:5 g / L, and placed in an 85°C water bath oscillator at a speed of 200 r / min for 20 min to obtain intermediate product I. Intermediate product I was mixed with n-hexane at a solid-liquid ratio of 1:2 g / L, and then oscillated in a 40°C water bath for 5 min, then heated to 70°C and maintained for 10 min to evaporate the solvent, filtered, and the filter residue was dried in an oven at 60°C for 3 h to obtain a mixed treated powder.

[0070] S2: Preparation of plant protein nanoparticles

[0071] S2.1: Take the mixed processed powder and mix it evenly with 6 times the volume of distilled water, adjust the pH to 11 with 1 mol / L NaOH solution, place it in a 50°C water bath oscillator at 100 r / min for 20 minutes, centrifuge to remove the precipitate, then add HCl solution to adjust the pH value of the supernatant to 4, let it stand for 20 minutes, separate the precipitate, wash the precipitate with water twice and air-dry it to obtain the extracted plant protein powder;

[0072] S2.2: Disperse the extracted plant protein powder in distilled water at a solid-liquid ratio of 1:5 g / mL, adjust the pH to 8 to obtain a plant protein solution, insert the titanium probe of an ultrasonic cell crusher into the plant protein solution 1 cm below the liquid surface, control the temperature to 0°C in an ice bath, perform ultrasonic oscillation for 30 minutes, and the ultrasonic oscillation power is 450 W. After freeze-drying the product, plant protein nanoparticles are obtained.

[0073] S3: Bacteria Activation

[0074] S3.1: Prepare 100 mL of potato glucose liquid medium with 200 g / L potato powder and 20 g / L glucose, sterilize and cool, and inoculate Aspergillus oryzae with a needle from a test tube in a sterile operating table, and culture at 34°C, 180 r / min for 76 h in a shaking incubator to obtain activated Aspergillus oryzae in the medium;

[0075] S3.2: Prepare 100 mL of liquid culture medium with 5 g / L broth, 3 g / L yeast powder, 5 g / L glucose, 1 g / L starch, 3 g / L sodium acetate and 0.5 g / L L-cysteine ​​hydrochloride. Use an inoculation needle to pick a loop from the test tube and inoculate Bifidobacterium bifidum TMC3115 on a sterile operating table. Incubate the mixture at 37°C in a constant temperature incubator for 26 hours to obtain activated Bifidobacterium bifidum.

[0076] S4: Preparation of plant protein peptide fermentation

[0077] S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1:2, and 30 mL is taken and put into a culture bottle. After sterilization and cooling, 2 mL of the activated Aspergillus oryzae bacterial solution is respectively taken with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly, and then cultured at 36°C in a constant temperature incubator for 24 hours to obtain a primary fermentation product;

[0078] S4.2: Weigh 1 part by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 125°C for 20 minutes, let stand and cool to 26°C, then add 3 parts by mass of primary fermentation product and 2mL of activated Bifidobacterium bifidum bacterial solution, seal with cotton plug, and culture on a shaker at 34°C, 180 r / min for 76 hours to obtain plant protein peptide fermentation product.

[0079] Comparative Example 1:

[0080] Compared with Example 1, the difference of Comparative Example 1 is that licorice is not added in step S1.1, specifically, "S1: treating the plants

[0081] S1.1: 20 parts by weight of Momordica grosvenori, 15 parts by weight of Purslane, 10 parts by weight of Lycium barbarum, 12 parts by weight of Citron, 15 parts by weight of Rose and 20 parts by weight of Phragmites australis were put into a grinder and crushed for 5 minutes to obtain a mixed slurry, and then the mixed slurry was mixed with NaCl solution at a solid-liquid ratio of 1:10 g / L, and finely crushed and beaten for 30 minutes to obtain a treated slurry;

[0082] S1.2: n-hexane and the treated slurry were mixed at a solid-liquid ratio of 1:5 g / L, and the mixture was placed in an 85°C water bath oscillator and oscillated at a speed of 200 r / min for 20 min to obtain an intermediate product I. The intermediate product I was mixed with n-hexane at a solid-liquid ratio of 1:2 g / L, and then oscillated in a 55°C water bath for 10 min, then heated to 75°C for 5 min to evaporate the solvent, filtered, and the residue was dried in an oven at 80°C for 4 h to obtain a mixed treated powder. The prepared plant protein peptide fermentation product was recorded as Comparative Example 1.

[0083] Comparative Example 2:

[0084] Compared with Example 1, the difference of Comparative Example 2 is that no NaCl solution is added in step S1.1, specifically: "S1: Treating the plants

[0085] S1.1: 40 parts by weight of licorice, 20 parts by weight of monk fruit, 15 parts by weight of purslane, 10 parts by weight of wolfberry, 12 parts by weight of citron, 15 parts by weight of rose and 20 parts by weight of reed root were put into a grinder and crushed for 5 minutes to obtain a mixed slurry, and then the mixed slurry was finely crushed and beaten for 30 minutes to obtain a treated slurry;

[0086] S1.2: n-hexane and the treated slurry were mixed at a solid-liquid ratio of 1:5 g / L, and the mixture was placed in an 85°C water bath oscillator and oscillated at a speed of 200 r / min for 20 min to obtain an intermediate product I. The intermediate product I was mixed with n-hexane at a solid-liquid ratio of 1:2 g / L, and then oscillated in a 55°C water bath for 10 min, then heated to 75°C for 5 min to evaporate the solvent, filtered, and the residue was dried in an oven at 80°C for 4 h to obtain a mixed treated powder. The prepared plant protein peptide fermentation product was recorded as Comparative Example 2.

[0087] Comparative Example 3:

[0088] Compared with Example 1, the difference of Comparative Example 3 is that step S4.1 is not performed, step S4.2 is performed directly and the primary fermentation product is replaced with plant protein nanoparticles, specifically: "S4: Preparation of plant protein peptide fermentation product

[0089] S4.1: Weigh 1 part by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 121°C for 15 min, let stand and cool to 24°C, then add 3 parts by mass of plant protein nanoparticles and 2 mL of activated Bifidobacterium bifidum bacterial solution, seal with cotton plugs, and culture on a shaker at 30°C and 160 r / min for 72 h to obtain a plant protein peptide fermentation product. The prepared plant protein peptide fermentation product is recorded as Comparative Example 3.

[0090] Comparative Example 4:

[0091] Compared with Example 1, the difference of Comparative Example 4 is that step S4.2 is not performed, and the primary fermentation product is directly used as the plant protein peptide fermentation product, specifically: "S4: Preparation of plant protein peptide fermentation product

[0092] S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1:2, and 30 mL is taken into a culture bottle. After sterilization and cooling, 2 mL of the activated Aspergillus oryzae bacterial solution is respectively drawn with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly. The mixture is statically cultured at 36°C in a constant temperature incubator for 24 hours to obtain a plant protein peptide fermentation product. The prepared plant protein peptide fermentation product is recorded as Comparative Example 4.

[0093] The yield and hydrolysis degree of the plant protein peptide fermentation products of Examples 1-3 and Comparative Examples 1-4 were statistically analyzed.

[0094] Table 1

[0095] Yield (%) Degree of hydrolysis (%) Example 1 60.5 45.9 Example 2 57.3 44.5 Example 3 58.6 45.3 Comparative Example 1 42.1 37.2 Comparative Example 2 45.9 36.6 Comparative Example 3 53.7 32.4 Comparative Example 4 52.5 30.8

[0096] The yields of Examples 1-3 are above 57.3%, and can reach up to 60.5%. The hydrolysis degrees of the plant protein peptide fermentations are 45.9%, 44.5% and 45.3%, respectively. The hydrolysis degree can reflect the content of small molecule proteins. Both of the examples are higher than the comparative examples. It can be seen that both the yield of the protein product and the hydrolysis degree of the fermentation product are better in the examples.

[0097] The yield of comparative example 1 is 42.1%, and the degree of hydrolysis is 37.2%. The yield of comparative example 2 is 45.9%, and the degree of hydrolysis is 36.6%. It can be seen that the addition of licorice and NaCl solution can increase the amount of protein precipitation, thereby increasing the yield of plant protein peptide fermentation products, while the increase in hydrolysis degree is relatively limited. This is because the conversion into small molecule proteins mainly requires a fermentation step. When the fermentation steps are the same, the change in hydrolysis degree is small.

[0098] The yield of Comparative Example 3 is 53.7%, the yield of Comparative Example 4 is 52.5%, and the hydrolysis degrees are 32.4% and 30.8%, respectively. The yields of Comparative Examples 3 and 4 are slightly different from those of the embodiment, while the hydrolysis degrees are greatly reduced, indicating that the content of small molecule proteins has decreased. It can be seen that the asynchronous fermentation interaction between Aspergillus oryzae and Bifidobacterium bifidum can better decompose plant proteins, thereby increasing the content of small molecule proteins and making the plant protein peptide fermentation easier to absorb.

[0099] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for preparing a plant protein peptide fermentation product, characterized in that: The steps include: S1: Treating plants Grind licorice, monk fruit, purslane, wolfberry, citron, rose and reed root in a grinder to obtain a mixed slurry, mix the mixed slurry with a NaCl solution to obtain a treated slurry, mix n-hexane with the treated slurry to obtain an intermediate product I, mix the intermediate product I with n-hexane, then heat and evaporate to remove the solvent, filter, and dry the filter residue to obtain a mixed treated powder; S2: Preparation of plant protein nanoparticles The mixed processed powder is mixed with distilled water, shaken and centrifuged to remove precipitates, the pH value is adjusted, and the precipitates are separated after standing to obtain extracted plant protein powder, the extracted plant protein powder is dispersed in distilled water to obtain a plant protein solution, an ultrasonic cell pulverizer titanium probe is inserted under the liquid surface of the plant protein solution, ultrasonically shaken, and the product is freeze-dried to obtain plant protein nanoparticles; S3: Bacteria Activation Prepare a potato glucose liquid culture medium, sterilize and cool it, and then use an inoculation needle to pick a loop from a test tube to inoculate Aspergillus oryzae for culture, so as to obtain activated Aspergillus oryzae in the culture medium, prepare a liquid culture medium, and use an inoculation needle to pick a loop from a test tube to inoculate Bifidobacterium bifidum for culture, so as to obtain activated Bifidobacterium bifidum; S4: Preparation of plant protein peptide fermentation After the activation of the strain is completed, the bran and distilled water are mixed and put into a culture bottle. After sterilization and cooling, the bacterial solution of activated Aspergillus oryzae is respectively drawn with a sterile pipette and added to the culture bottle for cultivation to obtain a primary fermentation product. The plant protein nanoparticles are weighed, distilled water is added, sterilized, and the primary fermentation product and activated Bifidobacterium bifidum bacterial solution are added for cultivation to obtain a plant protein peptide fermentation product.

2. The method for preparing a plant protein peptide fermentation product according to claim 1, characterized in that: Step S1 processes the plants, including the following steps: S1.1: 40-80 parts by weight of licorice, 20-50 parts by weight of monk fruit, 15-30 parts by weight of purslane, 10-30 parts by weight of wolfberry, 12-18 parts by weight of citron, 15-30 parts by weight of rose and 20-25 parts by weight of reed root are put into a grinder and crushed for 5-10 minutes to obtain a mixed slurry, and then the mixed slurry is mixed with NaCl solution at a solid-liquid ratio of 1: (8-10) g / L, and finely crushed and beaten for 30-50 minutes to obtain a treated slurry; S1.2: n-hexane and the treated slurry are mixed at a solid-liquid ratio of 1:(5-8) g / L, and placed in a 65-85°C water bath oscillator at a speed of 150-200 r / min for 10-20 min to obtain intermediate product I. The intermediate product I is mixed with n-hexane at a solid-liquid ratio of 1:(2-3) g / L, and then oscillated in a 40-55°C water bath for 5-10 min, then heated to 70-75°C and maintained for 5-10 min to evaporate the solvent, filtered, and the filter residue is dried in an oven at 60-80°C for 3-4 h to obtain a mixed treated powder.

3. The method for preparing a plant protein peptide fermentation product according to claim 2, characterized in that: Step S2 is preparing plant protein nanoparticles, comprising the following steps: S2.1: Take the mixed processed powder and mix it evenly with 6-8 times volume of distilled water, adjust the pH to 10-11 with 1-2 mol / L NaOH solution, place it in a 50-60℃ water bath oscillator at 100-150r / min for 20-30min, centrifuge to remove the precipitate, add HCl solution to adjust the pH value of the supernatant to 4-4.5, let it stand for 20-25min, separate the precipitate, wash the precipitate with water 2-3 times and air-dry it to obtain the extracted plant protein powder; S2.2: Disperse the extracted plant protein powder in distilled water at a solid-liquid ratio of 1:(5-10) g / mL, adjust the pH to 8-8.5 to obtain a plant protein solution, insert the titanium probe of an ultrasonic cell crusher 1-2 cm below the liquid surface of the plant protein solution, control the temperature to 0-4°C in an ice bath, perform ultrasonic oscillation for 20-30 minutes, and freeze-dry the product to obtain plant protein nanoparticles.

4. The method for preparing a plant protein peptide fermentation product according to claim 3, characterized in that: In step S2.2, the ultrasonic oscillation power is 400-500W.

5. The method for preparing a plant protein peptide fermentation product according to claim 1, characterized in that: Step S3: bacterial activation, comprising the following steps: S3.1: Prepare 100-200 mL of potato glucose liquid medium with 200-220 g / L of potato powder and 20-25 g / L of glucose, sterilize and cool, inoculate Aspergillus oryzae with an inoculation needle from a test tube, and culture on a shaker at 30-34°C and 160-180 r / min for 72-76 h to obtain activated Aspergillus oryzae in the medium; S3.2: Prepare 100-200 mL of liquid culture medium with 5-10 g / L broth, 3-5 g / L yeast powder, 5-10 g / L glucose, 1-3 g / L starch, 3-5 g / L sodium acetate and 0.5-0.8 g / L L-cysteine ​​hydrochloride. In a sterile operating table, use an inoculation needle to pick a loop from a test tube to inoculate Bifidobacterium bifidum. Incubate at 36-37° C. in a constant temperature incubator for 24-26 hours to obtain activated Bifidobacterium bifidum.

6. The method for preparing a plant protein peptide fermentation product according to claim 5, characterized in that: The Bifidobacterium bifidum in step S3.2 is specifically Bifidobacterium bifidum TMC3115.

7. The method for preparing a plant protein peptide fermentation product according to claim 1, characterized in that: Step S4 is preparing a plant protein peptide fermentation product, comprising the following steps: S4.1: After the activation of the strain is completed, bran and distilled water are mixed in a mass ratio of 1: (2-3), and 30-40 mL is taken and put into a culture bottle. After sterilization and cooling, 2-3 mL of the activated Aspergillus oryzae bacterial solution is respectively taken with a sterile pipette and added to the culture bottle, and the bacterial solution and bran are stirred with a sterile glass rod to mix evenly, and then cultured in a constant temperature incubator at 36-37° C. for 24-26 hours to obtain a primary fermentation product; S4.2: Weigh 1-1.5 parts by mass of plant protein nanoparticles, add distilled water to a moisture content of 40%, sterilize at 121-125°C for 15-20 min, let stand and cool to 24-26°C, then add 3-4 parts by mass of primary fermentation product and 2-3mL of activated Bifidobacterium bifidum culture solution, seal with cotton plug, and culture on a shaker at 30-34°C, 160-180r / min for 72-76h to obtain plant protein peptide fermentation product.

8. A plant protein peptide fermentation product, which is prepared by the method for preparing a plant protein peptide fermentation product according to any one of claims 1 to 7.

9. Use of a plant protein peptide fermentation product, wherein the plant protein peptide fermentation product prepared by the method for preparing a plant protein peptide fermentation product according to any one of claims 1 to 7 is added to health food.

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