Fertilizer for preventing and treating citrus liberobacter asiaticum based on biological protein principle

Abstract

The invention relates to the technical field of fertilizers, and discloses a biological protein principle-based fertilizer for preventing and treating citrus liberobacter asiaticum, which is prepared from the following raw materials in parts by weight: 40 to 70 parts of fish protein peptide fermentation products, 5 to 15 parts of EM flora active liquid, 1 to 5 parts of chelated trace element solution and 10 to 20 parts of algal polysaccharide-polyglutamic acid compound. The fish protein peptide is fermented for 180 days or longer through EM bacteria. The EM flora active liquid contains lactic acid bacteria, photosynthetic bacteria, actinomycetes and saccharomycetes. The trace elements are at least two of boron, zinc, iron, manganese and molybdenum and are chelated by polyglutamic acid or sugar alcohol. The small peptide, the bacterial metabolite and the chelate element are in slow release synergy, so that rhizosphere microecology can be rebuilt, defensive enzymes can be induced, and the phenomena of huanglong, yellowing and red nose can be relieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fertilizers, in particular to a fertilizer for preventing and treating citrus Huanglongbing based on the principle of biological protein. BACKGROUND

[0002] Citrus Huanglongbing (Huanglongbing, HLB for short) is one of the most destructive diseases in the citrus industry, which is a bacterial disease. It is mainly transmitted through seedlings, scions, and psyllids. The leaves often have asymmetric yellow spots and are difficult to turn green. The fruit is easily deformed and inedible. The diseased tree usually dies from top to bottom within one to two years, and eventually the whole plant dies. In production practice, the spread is often controlled by cutting down the diseased trees, but this measure will cause significant economic losses and the risk of abandoning the orchard during the fruit-bearing period of the trees.

[0003] The existing prevention and control methods mainly focus on two ideas: one is chemical or antibiotic intervention, including using human / animal antibiotics as a tree trunk "hanging needle" injection treatment, hoping to inhibit the pathogen through the phloem. However, this method has drug compliance and food safety risks, and is high in operation intensity, which is not conducive to large-scale promotion. The second is nutrition and micro-ecological conditioning, such as the treatment method of combining small molecule peptide polyglutamic acid fertilizer, trace element fertilizer, and EM bacteria liquid, and implementing through foliar, trunk spraying, and root irrigation along the drip line, in order to improve soil activity and tree stress resistance.

[0004] However, methods such as trunk injection are time-consuming and labor-intensive, and are difficult to cover large areas of orchards. The Huanglongbing pathogen is limited to the phloem, and exogenous spraying or short-term flushing is difficult to achieve long-term, controlled release, and stable supply in the rhizosphere. SUMMARY

[0005] In view of this, the present application provides a fertilizer for preventing and treating citrus Huanglongbing based on the principle of biological protein, which aims to solve the problems existing in the above content.

[0006] On the one hand, the present application provides a fertilizer for preventing and treating citrus Huanglongbing based on the principle of biological protein, which comprises the following raw materials by weight:

[0007] 40-70 parts of fish protein peptide fermentation product;

[0008] 5-15 parts of EM bacteria group active liquid;

[0009] 1-5 parts of chelated trace element solution;

[0010] 10-20 parts of seaweed polysaccharide-polyglutamic acid complex;

[0011] Among them:

[0012] The fish protein peptide fermentation product is obtained by continuously fermenting fish body or fish viscera powder into 2-5 mm particles under anaerobic conditions for not less than 180 days, wherein the small molecule polypeptides with a molecular weight of less than 3000 Da account for not less than 60% of the total amount of proteins, the mass fraction of free amino acids is 10-20% based on the total nitrogen, and the mass concentration of organic acid is 8-15 g / L of lactic acid;

[0013] The EM microbial population active liquid is composed of lactic acid bacteria, photosynthetic bacteria, actinomycetes and yeast, and the total number of viable bacteria is not less than 1.0 x 10 7 CFU / mL, and the pH is 4.2-4.6;

[0014] The chelated trace element solution contains at least two of boron, zinc, iron, manganese and molybdenum, and the chelated trace elements are complexed with polyglutamic acid or sugar alcohol, and the molar ratio of metal ions to complexing groups is 1:(1.5-3.0);

[0015] The seaweed polysaccharide-polyglutamic acid complex is obtained by cross-linking seaweed polysaccharide and polyglutamic acid at a mass ratio of 2:1 at pH = 5.2-5.8, and the combined water content is 8-12%.

[0016] Further, the lactic acid bacteria in the EM microbial population active liquid are at least one of Lactobacillus plantarum or Lactococcus lactis, the photosynthetic bacteria are at least one of Rhodococcus photosynthetic bacteria or Rhodospirillum photosynthetic bacteria, the actinomycetes are at least one of Streptomyces griseus or Aureusmycin streptomyces, and the yeast is at least one of Saccharomyces cerevisiae or Pichia pastoris, and the initial viable count of each bacterium in the EM microbial population active liquid is not less than 1.0 x 10 6 , 1.0 x 10 5 , 1.0 x 10 5 , 1.0 x 10 6 CFU / mL, respectively.

[0017] In another aspect, the present application also provides a method for preparing the above-mentioned fertilizer based on biological protein principle for preventing and treating citrus Huanglongbing, comprising the following steps:

[0018] S1: The fish body or fish viscera is washed and crushed into 2-5 mm particles as raw material for standby, and is incubated at 60±2℃ for 20-30 min; the water content of the raw material is adjusted to 55-70%, the fat mass fraction is not higher than 12%, and the chloride mass fraction is not higher than 1.5%;

[0019] S2: The raw material is mixed with the compound microbial liquid at a ratio of 1 kg of raw material to (1.0-1.5) L of fermentation liquid; the initial pH is adjusted to 6.6-7.2, 3-5 times the volume of the container is replaced with nitrogen or carbon dioxide, the dissolved oxygen is controlled to be not higher than 0.5 mg / L, and the oxidation-reduction potential is-50 to-150 mV;

[0020] S3: sequentially performing I phase protein hydrolysis, II phase acidification and peptide enrichment, III phase maturation and IV phase stabilization in a closed corrosion-resistant container, and the cumulative fermentation time is greater than or equal to 180 days;

[0021] S4: standing and settling for 24-48 hours, performing 100-200 mesh filtration, and using vacuum concentration at 45-55 DEG C to concentrate the solid content to 30-40 wt.%;

[0022] S5: sequentially adding a chelated trace element solution and a seaweed polysaccharide-polyglutamic acid complex, stirring for 30-60 minutes at pH = 5.5-6.2, and obtaining the fertilizer.

[0023] Further, step S3 specifically comprises:

[0024] The first 0-30 days are I phase protein hydrolysis, the temperature is 35±2 DEG C, the stirring is performed once a day, each time for 10-20 minutes, and the stirring speed is 20-40 rpm;

[0025] The 31st-90th day is II phase acidification and peptide enrichment, the temperature is 32±2 DEG C, and the pH is 4.2-4.8;

[0026] The 91st-150th day is III phase maturation, the temperature is 30-34 DEG C, the stirring is performed once a week, each time for 10-15 minutes, and the lactic acid mass concentration is maintained at 8-15 g / L;

[0027] The 151st-180th day is IV phase stabilization, the temperature is 28-32 DEG C, and the photosynthetic bacteria and lactic acid bacteria are inoculated twice.

[0028] Further, in step S3, a closed fermentation container resistant to acid and corrosion is used, the proportion of gas in the fermentation container to the volume of the container is not higher than 10%, and nitrogen or carbon dioxide is replaced at the beginning of I phase and the beginning of II phase, so that the oxygen volume fraction after replacement is less than or equal to 0.5%.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] By continuously fermenting fish bodies or fish viscera under anaerobic conditions for not less than 180 days by a complex bacterial population, and under phased control, a fish protein peptide fermentation product mainly composed of small molecule polypeptides is obtained, so that small molecule polypeptides with a molecular weight of less than 3000 Da become the main component. Such small molecule polypeptides are more easily absorbed by roots and conducted along the phloem, and can directly participate in nitrogen assimilation and metabolic regulation, solving the problem of high proportion of macromolecules in conventional protein hydrolysates and unstable field absorption and utilization rate.

[0031] The fermentation process is carried out under low dissolved oxygen and controlled oxidation-reduction potential conditions, and the system pH is maintained in the acid window through lactic acid generation, thereby inhibiting the corruption metabolic pathway, reducing the formation of volatile nitrogen and biogenic amines and the like, and improving product safety and odor stability, and eliminating the hidden dangers of field adverse reactions caused by insufficient fermentation or improper end-point control.

[0032] After concentration and drying, EM microbial population active liquid composed of lactic acid bacteria, photosynthetic bacteria, actinomycetes and yeast is added according to the total number of viable bacteria and pH, taking into account product stability and field colonization ability. The combination not only provides organic acids, vitamins and antagonistic metabolites, but also forms a mutual promotion relationship with small molecule polypeptides, thereby improving tree nutrient absorption and stress resistance response from the rhizosphere microecological level.

[0033] The seaweed polysaccharide and polyglutamic acid are cross-linked in an acid condition to form a three-dimensional network in a mass ratio of 2:1, and the combined state water content is controlled, so that the fish protein peptide fermentation product and the chelated trace elements realize the dynamic balance of "adsorption-release-adsorption" in the rhizosphere, avoid short-term high peak impact, maintain sustained supply for a long period, and adapt to regular drip irrigation / flushing management in large-area orchards.

[0034] At least two of boron, zinc, iron, manganese and molybdenum are complexed with polyglutamic acid or sugar alcohol, so that the metal ions exist in a stable complex state, significantly reducing chemical fixation and antagonism in the soil-rhizosphere system, and improving the mobility and bioavailability in the roots and phloem, and synergistically improving chlorophyll maintenance and reproductive growth stability with small molecule polypeptides.

[0035] The product can be directly implemented by root application, drip irrigation / flushing and foliar spraying, without the need for tree trunk injection to achieve the prevention and control effect; it not only reduces the operation trauma and labor intensity, but also avoids the compliance and food safety risks of antibiotic medication in agricultural scenarios. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0037] Embodiment 1

[0038] The fertilizer 80 kg (moisture content about 6%, particle size 2-4 mm) is prepared in this embodiment. The formula is converted according to weight parts: fish protein peptide fermentation product 60 parts, EM microbial population active liquid 10 parts, chelated trace element solution 3 parts, seaweed polysaccharide-polyglutamic acid complex 15 parts (1 part

[0039] = 1 kg).

[0040] The fish protein peptide fermentation product is obtained by processing marine fish. In this embodiment, anchovy is used. It should be noted that angora fish or salmon can also be used.

[0041] Seaweed polysaccharide-polyglutamic acid complex

[0042] The specific dosages are as follows: spray-dried fish protein peptide fermentation product 60.0 kg (<3000 Da small peptides ≥ 60%, of which 500-1000 Da accounts for 20-30%, VBN ≤ 30 mg / 100 g, and histamine ≤ 50 mg / kg), EM microbial population active liquid 10.0 kg (combination of lactic acid bacteria, photosynthetic bacteria, actinomycetes, and yeast bacteria; total number of viable bacteria ≥ 1.0 × 10^8 CFU / mL, and pH is 4.3), chelated trace element solution 3.0 kg (Zn 2+ Fe 3+ Each 120 g of metal ions, metal: complexing group

[0043] = 1:2.0, the complexing agent is a mixture of amino acids, and the solid content of the solution is approximately 20%), seaweed polysaccharide-polyglutamic acid complex 15.0 kg (seaweed polysaccharide: polyglutamic acid = 2:1, crosslinking pH is 5.5, and the solid content of the complex is approximately 20%).

[0044] The preparation method is as follows: seaweed polysaccharide-polyglutamic acid complex 15.0 kg and pure water 8.0 kg are stirred at 300 rpm for 15 min in a stainless steel jacketed tank to make them uniform, and the pH is adjusted to 5.6;

[0045] Chelated trace element solution 3.0 kg is added, and stirring is performed at 400 rpm for 10 min to make the average particle size D50 about 1-2 μm;

[0046] EM microbial population active liquid 10.0 kg is slowly added dropwise (≤ 1 kg / min), and stirring is performed at 200 rpm for another 10 min;

[0047] The spray powder 60.0 kg is slowly added and atomized and sprayed into the above water phase (total water phase is about 28 kg) in a plowshare mixer, and the total mixing is performed for 10 min to make the moisture content of the material about 18%.

[0048] The finished product is retested: small peptides (<3000 Da) / total protein = 65.0%, of which 500-1000 Da is 25.1%; 1:10 water immersion liquid pH 4.5, lactic acid 10.5 g / L; 10 times rehydration count viable bacteria 3.0 × 10 7 CFU / mL; Zn in the product = 0.30% (w / w), Fe = 0.30% (w / w); T80 of small peptides and metal ions released in water medium at 25°C ≈ 31 days.

[0049] Example 2

[0050] This embodiment yielded 80 kg of functional fertilizer granules. The formula consisted of: 55 parts fish protein peptide fermentation product, 8 parts EM (Effective Microorganisms) active liquid, 3 parts chelated trace element solution, and 18 parts seaweed polysaccharide-polyglutamic acid complex. Specific feed amounts were: 55.0 kg of spray powder; 8.0 kg of EM active liquid (≥1.0 × 10⁻⁶). 8 CFU / mL, pH 4.3); 3.0 kg of chelated trace element solution (120 g each of B and Zn, metal:complex group = 1:1.8); 18.0 kg of seaweed polysaccharide-polyglutamic acid complex (crosslinking pH 5.4, solids ≈ 20%); 10 kg of granulation wetting water.

[0051] The process steps are the same as in Example 1.

[0052] Finished product specifications: Small peptides (<3000Da) 63.2%, 500–1000Da 23.0%; Rehydrated live bacteria 2.6 × 10⁻⁶ 7 CFU / mL; B = 0.12%, Zn = 0.30%; sustained-release T80 ≈ 33 days.

[0053] Example 3

[0054] In this embodiment, 1,000 L of liquid was prepared (approximately 1,180 kg, solids content 35% ± 0.5%, viscosity < 120 mPa·s at 25°C). The formula consisted of 40 parts fish protein peptide fermentation product, 12 parts EM bacterial activity solution, 3 parts chelated trace element solution, and 15 parts seaweed polysaccharide-polyglutamic acid complex. The calculated feed amounts were: 472 kg of concentrated fish protein peptide fermentation product (solids ≈ 35%), and 354 kg of EM bacterial activity solution (≥ 1.0 × 10⁻⁶ mPa·s). 8 CFU / mL), 88.5 kg of chelated trace element solution (total metals approximately 7.1 kg, metal: complexing group)

[0055] =1:2.0), 265.5 kg of seaweed polysaccharide-polyglutamic acid complex (solids ≈20%), then added pure water to a total mass of 1,180 kg. Preparation sequence: First, form an aqueous phase with seaweed polysaccharide-polyglutamic acid complex and pure water, add chelation solution and stir evenly, add EM bacterial activity solution, and add fish protein peptide concentrate in a separate container. Homogenize online at 3000 rpm × 3 min, short-time shear at 6000 rpm × 1 min, degas at -0.06 MPa vacuum for 5 min, and then filter through a 0.45 μm security filter without sterilization and fill into the final product. Finished product: solids 35.2%, small peptides (<3000 Da) 61.8%, live bacteria 1.1 × 10⁻⁶ 8 CFU / mL, no metal precipitation or flocculation was observed at room temperature for 30 days.

[0056] Comparative Example 1

[0057] Short cycle fermentation 60 days, only I+II phase, same S1-S2 starting conditions as example 1, but only I phase and II phase in S3, total fermentation 60 days; the rest S4, S5 same as example one and keep the same charge. Semi-finished product: small peptides (<3000 Da) 41%, of which 500-1000 Da 11%, lactic acid 4.2 g / L, VBN 58 mg / 100 g, group

[0058] Amine > 60 mg / kg. Finished product granules rehydrated viable bacteria 1.1 x 10 7 CFU / mL.

[0059] Comparative Example 2

[0060] The difference between this comparative example and example 1 is that the fucoidan-polyglutamic acid complex is removed.

[0061] Based on example 1, delete fucoidan-polyglutamic acid complex, increase wet water to 15-18 kg, the rest unchanged.

[0062] Comparative Example 3

[0063] Based on example 1, replace 3.0 kg of chelated trace element solution with an aqueous solution of ZnSO4·7H2O 0.66 kg and FeSO4·7H2O 0.48 kg of equal metal amount, without adding complexing agent; the rest unchanged. Product 1:10 extract appears visible precipitate in 24-48 h, individual leaf appears local chlorosis after spraying.

[0064] Test examples 1-3 and comparative examples 1-3 are tested, and the test items and test methods are as follows:

[0065] 1) Molecular weight distribution (small peptide spectrum): sampling (1.0 g of solid conversion), water dissolution, 0.22 μm filtration; GPC-HPLC (volume exclusion), external standard with 500, 1000, 3000 Da standard peptides; integral <3000 Da and 500-1000 Da proportion.

[0066] 2) Lactic acid: HPLC (C18, isocratic mobile phase water: acetonitrile containing 0.1% phosphoric acid), external standard quantitative method.

[0067] 3) Histamine: HPLC-UV (or fluorescence derivation) external standard method.

[0068] 4) Trace elements and heavy metals: sample nitric acid digestion ICP-MS (Zn, Fe, B, Pb, As, etc.).

[0069] 5) Total number of viable bacteria: plate count method (suitable selective medium, 37°C for 48 h), 10 times the preparation rehydration.

[0070] 6) Chelate stability (challenge test): equal metal amount samples in pH 6.0, 0.01 mol / L CaCl2, 25 °C, shaking for 24 h; 0.22 pm filtration, then measure supernatant soluble metal ratio (ICP-MS), and record turbidity (NTU) at the same time.

[0071] 7) Slow release performance: granules in dialysis bag (cut-off 3 kDa), in deionized water (25 °C), measure supernatant small peptide and metal concentration at regular time; fit T80 (time required for 80% release).

[0072] 8) Storage stability: 25 °C, light-avoiding for 30 d, measure viable bacteria retention rate, metal precipitation (soluble metal ratio change).

[0073] 9) Field index determination:

[0074] a. SPAD: SPAD-502, average of 20 leaves per plant at fixed site;

[0075] b. Root activity: TTC reduction method (pg·g -1 ·h -1 );

[0076] c. Disease index DI: 0-9 grade grading formula conversion %;

[0077] d. Defense enzyme activity: POD, PAL, PPO (kit method, U·g -1 fresh weight);

[0078] e. Yield and commodity fruit rate: conventional weighing and grading.

[0079] The test results are shown in Tables 1-6, wherein Examples 1-3 correspond to T1-T3 respectively, and Comparative Examples 1-3 correspond to C1-C3 respectively.

[0080] Table 1 Physicochemical and microbial indexes

[0081]

[0082] Table 2 Metals and heavy metals, solids / ingredients

[0083]

[0084] Note: C3 is non-chelated salt, see stability difference.

[0085] Table 3 Chelate stability and turbidity (pH 6.0, 0.01 mol / L CaCl2, 25 °C x 24 h)

[0086] Sample Soluble metal fraction (%) Turbidity (NTU) T1 ≥92 ≤1.5 T2 ≥92 ≤1.5 T3 ≥92 ≤1.5 C1 ≥90 ≤2.0 C2 ≥92 ≤1.8 C3 63–68 >10

[0087] Table 4 Release and storage stability

[0088] Sample Slow release T80 30 day viable bacteria retention (%) T1 ≈ 31 days ≥80 T2 ≈ 33 days ≥80 T3 Equivalent ≈ 30 days ≥85 C1 ≈ 9 days ≈60 C2 8-12 hours ≈75 C3 ≈ 12 days ≈75

[0089] Table 5 Physiological and disease parameters at 60 days in the field (mean ± SD; n = 5 plots)

[0090]

[0091] Table 6 Yield at 120 days in the field

[0092] Sample Fruit drop (%) Yield per plant (kg) T1 12.3±1.8 28.6±2.1 T2 13.5±2.0 27.9±2.0 T3 12.7±1.9 28.2±2.0 C1 18.9±2.5 23.1±1.8 C2 19.6±2.7 22.4±1.9 C3 20.3±2.8 21.8±1.7

[0093] Finally, it should be noted that the above examples are merely intended to illustrate the technical solutions of the present application and not to limit the same. Although the present application has been described in detail with reference to the above examples, those of ordinary skill in the art should understand that the specific embodiments of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application, and any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered within the protection scope of the claims of the present application.

Claims

1. A fertilizer based on the principle of biological proteins for the prevention and control of Huanglongbing (HLB) in citrus fruits, characterized in that, The ingredients include the following parts by weight: 40-70 parts of fish protein peptide fermentation product; 5-15 portions of EM bacterial culture active solution; 1-5 parts of chelated trace element solution; 10-20 parts of seaweed polysaccharide-polyglutamic acid complex; in: Fish protein peptide fermentation products are obtained by crushing fish bodies or fish viscera into 2-5 mm particles and then continuously fermenting them with EM bacteria under anaerobic conditions for no less than 180 days. The fish protein peptide fermentation products contain small molecule polypeptides with a molecular weight of less than 3000 Da, accounting for no less than 60% of the total protein, free amino acids with a mass fraction of 10-20% based on total nitrogen, and organic acids with a mass concentration of 8-15 g / L based on lactic acid. The EM microbial activity solution consists of lactic acid bacteria, photosynthetic bacteria, actinomycetes, and yeast, with a total viable count of no less than 1.0 × 10⁻⁶. 7 CFU / mL, pH 4.2-4.6; The chelated trace element solution contains at least two of the elements boron, zinc, iron, manganese and molybdenum, wherein the chelated trace elements are complexed with polyglutamic acid or sugar alcohol, and the molar ratio of metal ions to complexing groups is 1:(1.5-3.0). The seaweed polysaccharide-polyglutamic acid complex is formed by cross-linking seaweed polysaccharide and polyglutamic acid at a mass ratio of 2:1 under conditions of pH 5.2-5.8, with a bound water content of 8-12%.

2. The fertilizer for controlling Huanglongbing in citrus fruits based on the principle of biological proteins according to claim 1, characterized in that, The EM bacterial culture active solution contains *Lactobacillus plantarum* or *Lactococcus lactis*, photosynthetic bacteria *Rhodococcus* or *Rhodospirillum*, actinomycetes *Streptomyces griseus* or *Streptomyces chlortetracycline*, and yeast *Saccharomyces cerevisiae* or *Pichia pastoris*, with each bacterium having an initial viable count of no less than 1.0 × 10⁻⁶ cells / day in the EM bacterial culture active solution. 6 1.0×10 5 1.0×10 5 With 1.0×10 6 CFU / mL.

3. A method for preparing the fertilizer based on the principle of biological proteins for the prevention and control of Huanglongbing (HLB) in citrus fruits, as described in any one of claims 1-2, characterized in that, Includes the following steps: S1: After cleaning the fish body or internal organs, crush them into 2-5mm particles and set them aside as raw materials. Keep them at 60±2℃ for 20-30 minutes. Adjust the moisture content of the raw materials to 55-70%, the fat mass fraction to no more than 12%, and the chloride mass fraction to no more than 1.5%. S2: Mix raw materials and compound bacterial solution at a ratio of 1 kg raw material: (1.0-1.5) L fermentation broth; adjust the initial pH to 6.6-7.2; replace 3-5 times the container volume with nitrogen or carbon dioxide; control dissolved oxygen not to exceed 0.5 mg / L; and maintain the oxidation-reduction potential at -50 to -150 mV. S3: The fermentation process is carried out sequentially in a sealed, corrosion-resistant container, including Phase I protein hydrolysis, Phase II acidification and peptide enrichment, Phase III maturation and Phase IV stabilization, with a cumulative fermentation time of ≥180 days. S4: Let stand and settle for 24-48 hours, filter with 100-200 mesh, and concentrate under vacuum at 45-55℃ until the mass fraction of solids is 30-40%. S5: Add chelated trace element solution and seaweed polysaccharide-polyglutamic acid complex sequentially, and stir for 30-60 minutes at pH 5.5-6.2 to obtain fertilizer.

4. The method according to claim 3, characterized in that, Step S3 specifically includes: Days 0-30 are Phase I protein hydrolysis, at a temperature of 35±2℃, with stirring once a day for 10-20 minutes at 20-40 rpm. Days 31-90 are Phase II acidification and peptide enrichment, at a temperature of 32±2℃ and a pH of 4.2-4.

8. Days 91-150 are the third stage of maturation, with a temperature of 30-34℃, stirring once a week for 10-15 minutes, and maintaining a lactic acid concentration of 8-15 g / L. Days 151-180 are the stable period of stage IV, with a temperature of 28-32℃, followed by a second inoculation with photosynthetic bacteria and lactic acid bacteria.

5. The method according to claim 3, characterized in that, In step S3, an acid- and corrosion-resistant sealed fermentation container is used. The proportion of gas in the fermentation container to the container volume is no more than 10%. Nitrogen or carbon dioxide is replaced at the beginning of stage I and stage II, respectively, so that the oxygen volume fraction after replacement is ≤0.5%.

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