Soybean feed and preparation method thereof

Abstract

The invention provides a soybean feed and a preparation method thereof. The fermented soybean feed is prepared from compound microbial preparations including plant lactic acid bacteria, bacillus subtilis and saccharomyces cerevisiae. The preparation process is simple, the product quality is excellent, the use of antibiotics is reduced, the digestibility and functional nutritional value of feed soybeans are improved, the utilization rate of livestock and poultry feed can be effectively improved, the slaughtering rate can be improved, and the feed conversion ratio can be reduced.

Description

Technical Field

[0001] The invention belongs to the field of biological fermentation feed, and particularly relates to soybean feed and a preparation method thereof. Background Art

[0002] Soybean is the most important plant protein source for livestock and poultry, especially young livestock and poultry. It has a high crude protein content and a relatively balanced amino acid composition. However, soybean contains a variety of anti-nutritional factors such as antitrypsin, soybean agglutinin, phytic acid, oligosaccharides, soybean globulin, etc., which seriously affect the digestion and absorption of nutrients, reduce the immunity of livestock and poultry, and increase feeding costs. Fermented feed uses beneficial microorganisms to ferment and eliminate anti-nutritional factors in feed and feed raw materials. A large number of beneficial microorganisms, organic acids and microbial metabolites will be produced during the fermentation process. Fermented feed is rich in amino acids, vitamins, proteases, lactic acid and beneficial microorganisms required by animals. Long-term feeding can increase feed intake, improve digestibility, enhance immunity and reduce feeding costs.

[0003] The existing technology of preparing fermented soybeans using biological fermentation technology has many defects, such as single fermentation bacteria, unstable content of beneficial bacteria in the finished product, and incomplete removal of anti-nutritional factors. Summary of the invention

[0004] In view of the above problems, the present invention provides a soybean feed and a method for preparing fermented soybeans using a composite microbial preparation.

[0005] To achieve the above object, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing a fermented soybean feed, comprising the following steps: (1) crushing the soybean raw material through a 20-40 mesh sieve, adding a certain proportion of auxiliary materials and mixing, filling the fermentation tank as a fermentation medium, autoclaving for 30 minutes, and cooling for use; (2) inoculating the composite microbial preparation into the fermentation tank of step (1) at a mass ratio of 3% to 5% of the fermentation medium in step (1), and sealing the fermentation tank to prevent moisture from escaping; (3) Fermenting the mixture at 30-35° C. for 2-15 days to obtain fermented soybeans.

[0006] The composite microbial preparation is composed of composite fermentation strains and fermentation regulators. The composite fermentation strains include plant lactic acid bacteria, Bacillus subtilis and Saccharomyces cerevisiae. The bacterial content of each fermentation strain is not less than 1×10 cfu / mL.

[0007] The composite fermentation bacteria and the fermentation regulator are mixed in a mass ratio of 1:(1-6); Preferably, the mass ratio of the composite fermentation bacteria to the starter is 1:3.

[0008] The composite fermentation bacteria are plant lactic acid bacteria, Bacillus subtilis, and Saccharomyces cerevisiae mixed in a ratio of (1-4): (2-6): (3-7), and the bacterial content is calculated in cfu / mL; Preferably, the mixing ratio of plant lactic acid bacteria, Bacillus subtilis and Saccharomyces cerevisiae is 2:6:4, calculated in terms of bacterial content cfu / mL.

[0009] Among them, the plant lactic acid bacteria, named plant lactic acid bacteria BFC1602, is deposited in the General Microbiological Center of China Microorganism Culture Collection Administration (CGMCC), with the deposit number CGMCC No.13132 and the deposit date October 21, 2016; Bacillus subtilis, named Bacillus subtilis BFC1601, deposited in China General Microbiological Culture Collection Center (CGMCC), with the deposit number CGMCC No.13131, and the deposit date was October 21, 2016; The cerevisiae yeast, named as cerevisiae BFC1603, was deposited in the General Microbiology Center of China Microorganism Culture Collection (CGMCC) with the deposit number CGMCC No.13133 and the deposit date on October 21, 2016.

[0010] The fermentation regulator includes KHPO, KHPO, NaCl, MgSO and HO in a mass ratio of: (1-7): (1-6): (2-8): (3-10): (1-4); the preferred mass ratio is 4:3:5:7:2.

[0011] The auxiliary materials include corn flour, ammonium sulfate, urea and water.

[0012] The ratio of soybeans and auxiliary materials in the fermentation medium is: the mass ratio of soybeans, corn flour, ammonium sulfate, urea and water is (500-1200): (10-80): (1-10): (1-8): (1000-1800), for example, it can be 500:20:2:1:1200, 600:15:5:3:1100, 1000:50:8:7:1500; Preferably, the mass ratio of soybean, corn flour, ammonium sulfate, urea and water in the fermentation medium is 940:50:6:4:1500.

[0013] The fermentation time in step (3) is preferably 4 days.

[0014] The fermented soybean feed obtained in step (3) can be processed by the following steps: The fermented soybeans in step (3) are dried at 65° C. to a moisture content of 10-13%; and then crushed to keep the particles at 0.5-2 mm to obtain a dried fermented soybean product.

[0015] In a second aspect, the present invention provides soybean feed prepared by the fermentation method described in the first aspect.

[0016] According to the present invention, oligosaccharides such as stachyose, raffinose and sucrose in the soybean feed are completely removed, anti-nutritional factors are degraded by ≥95%; large molecular weight proteins above 43KD are completely degraded, and the content of small peptides below 20KD is ≥98%; the pH of the fermented soybeans is 4-5, and the sour aroma is obvious.

[0017] According to the present invention, after the fermented soybeans are dried, the content of plant lactic acid bacteria is not less than 3×10 cfu / g, the content of Bacillus subtilis is not less than 5×10 cfu / g, and the content of Saccharomyces cerevisiae is not less than 1×10 cfu / g.

[0018] Compared with the prior art, the present invention has the following advantages: (1) The soybeans are fermented with composite fermentation bacteria, which are diversified and have stable content; (2) The oligosaccharides in soybeans are completely degraded, effectively removing 95% of the anti-nutritional factors in soybeans; (3) The macromolecular proteins in soybeans can be decomposed into small molecular peptides, thereby improving the utilization rate of soybean protein; (4) The process of the present invention is simple to operate, has good stability, and is convenient for large-scale production. DETAILED DESCRIPTION

[0019] To further explain the technical means and effects of the present invention, the technical solution of the present invention is further described below in conjunction with the preferred embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without any creative work are within the scope of protection of the present invention. Example

[0020] (1) Preparation of fermentation medium: The soybean raw material was crushed through a 20-mesh sieve, and corn flour, ammonium sulfate, urea and water were added and mixed, wherein the mass ratio of soybean to corn flour, ammonium sulfate, urea and water was 940:50:6:4:1500; (2) Preparation of composite microbial preparations: Plant lactic acid bacteria BFC1602, Bacillus subtilis BFC1601 and Saccharomyces cerevisiae BFC1603 were selected as fermentation strains, and mixed in a ratio of 2:4:6, and the bacterial content was calculated in cfu / mL to form a composite fermentation strain; wherein the bacterial content of each strain was not less than 1×10 cfu / mL; KHPO, KHPO, NaCl, MgSO and HO are mixed in a mass ratio of 4:3:5:7:2 to form a fermentation regulator; the composite fermentation strain and the fermentation regulator are mixed in a mass ratio of 1:3 to form a composite microbial preparation; (3) Fill the fermentation medium into the fermentation tank, sterilize it by high pressure for 30 minutes, and cool it for later use; (4) inoculating the composite microbial preparation into a fermentation tank at a ratio of 5% by mass of the fermentation medium, and sealing the tank to prevent moisture from escaping; (5) Fermenting at 30-35°C for 4 days to obtain fermented soybean feed, which can be directly packaged and marketed; (6) Drying the fermented soybeans at 65° C. until the moisture content is 10-13%; then crushing the soybeans so that the product particles are kept between 0.5 and 2 mm to obtain a dried fermented soybean product, which is packaged and marketed.

[0021] Example 2: Macromolecular protein content in fermented soybean feed This example uses polyacrylamide gel electrophoresis (SDS-PAGE) to analyze the degradation of macromolecular proteins before and after soybean fermentation. SDS-PAGE is an economical, rapid and repeatable method for quantifying, comparing and characterizing proteins. The steps are as follows: (1) preparing separation gel: preparing 30% acrylamide stock solution, 10% sodium dodecyl sulfate (SDS), electrophoresis buffer, Coomassie brilliant blue staining solution, methanol decolorizing solution and other reagents; after preparing the separation gel, further preparing a concentrated gel and placing it in a gel tank; (2) Weigh 1 g of fermented soybeans and add 20 mL of 0.03 mol / L trichloroacetic acid. Shake once every 20 min, soak and extract at room temperature for 1 h, centrifuge at 10,000 rpm for 10 min, and obtain the supernatant for spotting; (3) Take 80 μL of the supernatant and add 20 μL of buffer solution, and place in a boiling water bath for 3 min to obtain a sample solution; (4) Take 10 μL of the sample solution and add it to the gel tank of the protein electrophoresis instrument. Turn on the switch to perform vertical electrophoresis. End the electrophoresis when the blue band of the sample buffer migrates to the bottom of the gel. (5) Remove the gel, stain it, then destain it, and finally take a photo and save it.

[0022] Through the observation and analysis of electrophoresis bands, the content of large molecular weight proteins above 20kD in soybeans was very high before fermentation. After fermentation, all large molecular weight proteins above 43KD in soybeans were degraded, and the content of small peptides below 20KD was ≥98%.

[0023] Example 3: Antibacterial effect of the fermentation broth of the composite microbial preparation The inhibition zone measurement is a classic method of microbial analysis. The inhibition zone measurement method is used to determine the antibacterial effect of the fermentation broth of the composite microbial preparation by using the antibacterial substance to diffuse in a spherical three-dimensional shape in the agar medium coated with specific test bacteria, inhibiting the reproduction of the test bacteria and forming a transparent circle around the antibacterial substance, i.e., the inhibition zone. This embodiment uses the inhibition zone measurement method to determine the antibacterial effect of the fermentation broth of the composite microbial preparation.

[0024] Pour 10mL of plain agar into the plate. After solidification, gently immerse the Oxford cup into the plain agar. Dilute the Escherichia coli to 10. Take 15mL of LB medium and pour it evenly on the plate. After solidification, remove the Oxford cup and add 100uL of blank control solution and compound microbial preparation fermentation liquid into the hole with a pipette. Diffuse it in a 4℃ refrigerator for 1h, then culture it in a 37℃ incubator for 12h. Observe and measure the diameter of the inhibition zone with a vernier caliper.

[0025] The diameter of the inhibition zone of the blank control group measured with a vernier caliper was 0, while the diameter of the inhibition zone of the fermentation broth of the composite microbial preparation was 23.8 mm.

[0026] The present invention illustrates the detailed method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed method, that is, it does not mean that the present invention must rely on the above-mentioned detailed method to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing soybean feed, It is characterized in that The following steps are involved: (1) Grind the soybean raw material through a 20-40 mesh sieve, add a certain proportion of auxiliary materials and mix well, fill it into a fermentation tank as a fermentation medium, sterilize it under high pressure for 30 minutes, and cool it for use; (2) inoculating the composite microbial preparation into the fermentation tank of step (1) at a mass ratio of 3% to 5% of the fermentation medium in step (1), and sealing the tank to prevent moisture from escaping; (3) Fermenting at 30-35°C for 2-15 days to obtain fermented soybean feed.

2. The method according to claim 1, It is characterized in that The composite microbial preparation consists of composite fermentation strains and a fermentation regulator. The composite fermentation strains include plant lactic acid bacteria, Bacillus subtilis and Saccharomyces cerevisiae. The bacterial content of each fermentation strain is not less than 1×10 cfu / mL.

3. The method according to claim 2, It is characterized in that The composite fermentation bacteria and the fermentation regulator in the composite microbial preparation are mixed in a mass ratio of 1:(1-6); more preferably, the mass ratio of the composite fermentation bacteria and the fermentation regulator is 1:

3.

4. The method according to claim 2 or 3, It is characterized in that The ratio of plant lactic acid bacteria, Bacillus subtilis and Saccharomyces cerevisiae in the composite fermentation strain is (1-4): (2-6): (3-7).

5. The method according to any one of claims 2 to 4, It is characterized in that The auxiliary materials include corn flour, ammonium sulfate, urea and water; the ratio of soybeans to auxiliary materials in the fermentation medium is: the mass ratio of soybeans, corn flour, ammonium sulfate, urea and water is (500-1200): (10-80): (1-10): (1-8): (1000-1800).

6. The method according to any one of claims 2 to 5, It is characterized in that The fermentation time in step (3) is 4 days.

7. The soybean feed prepared by the method according to any one of claims 1 to 6, It is characterized in that The anti-nutritional factors in the fermented soybeans are degraded by more than 95%, the content of small peptides below 20KD is 98%, and the pH value of the fermented soybeans is 4-5.

8. The soybean feed according to claim 7, It is characterized in that After the soybean feed is dried, the plant lactic acid bacteria content is not less than 3×10 cfu / g, the Bacillus subtilis content is not less than 5×10 cfu / g, and the brewer's yeast content is not less than 1×10 cfu / g.