CN110074256B

CN110074256B - Feed for improving milk fat rate of ruminant and preparation method thereof

Info

Publication number: CN110074256B
Application number: CN201910506851.6A
Authority: CN
Inventors: 梁云; 曹晟; 王身健
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-06-12
Filing date: 2019-06-12
Publication date: 2023-03-31
Anticipated expiration: 2039-06-12
Also published as: CN110074256A

Abstract

The invention relates to the technical field of livestock feed, and discloses feed for improving the milk fat rate and unsaturated fatty acid content in milk of ruminants, which comprises a core and a shell, wherein the core contains microbial thallus, and the shell contains a tumor-treating stomach protective agent; the microbial thallus is subjected to wall breaking treatment. The thallus feed of the invention can protect the grease and protein in the feed from being decomposed in the rumen of the ruminant, and improve the milk fat rate of the ruminant and the content of polyunsaturated fatty acid in the milk. The invention also provides a preparation method of the thallus feed, which comprises the following steps: the method comprises the following steps: 1) Performing wall breaking treatment on the microbial thallus to obtain wall-broken microbial thallus; 2) And coating the wall-broken microbial cells with a tumor-gastric protective agent. The method has the advantages of simple process, good rumen-protected effect, and high processing efficiency.

Description

Feed for improving milk fat rate of ruminant and preparation method thereof

Technical Field

The invention relates to the technical field of livestock feed, in particular to feed for improving the milk fat rate of ruminants and a preparation method of the feed.

Background

The milk produced by ruminant cattle and sheep contains rich mineral elements such as calcium, phosphorus, iron, zinc and the like, and the main components of the milk are water, protein, fat, phospholipid and lactose, and because of the proper calcium-phosphorus ratio and rich nutrition, the milk is increasingly accepted by the public; with the deep research of nutriology, the requirements on the quality of cow milk and goat milk are higher and higher, and the quality of cow milk and goat milk is highly related to the feeding condition and the quality of feed. Under the foundation, the feed technology for feeding cattle and sheep is promoted.

During the peak period of milk production, the insufficient energy intake of cows and goats, especially high-producing cows and goats, is easy to occur, and the energy supply can not meet the requirement, thus resulting in negative energy balance, and activating the energy supply by body tissues, especially body fat. Therefore, the weight reduction and the genetic potential exertion of the dairy cows and the dairy sheep are easily hindered, the emaciation of the dairy cows and the dairy sheep in the early lactation period and the reduction of the milk yield are caused, and the metabolic dysfunction of the dairy cows and the dairy sheep and the ketosis and other diseases can be caused in severe cases. Therefore, the high-yield cows and sheep need to be enriched and supplemented with two key nutrients, namely grease and protein in the feed. 65% of the fat in the feed fat will be used for milk formation.

Methods for supplementing proteins and fats in ruminant feed by adding oleaginous microbial cells such as microalgae whole cell powder to the feed have been known. The method for producing protein and fat by microbial transformation is a method which has low cost and is easy for large-scale high production. The oil-producing microorganism synthesizes oil and high-content protein at the same time. In addition, the content of unsaturated fatty acid in the synthesized grease in the oil-producing microorganism is far higher than that in the conventional vegetable oil, and most of the unsaturated fatty acid is functional unsaturated fatty acid. The microbial oil containing functional unsaturated fatty acid, which is industrially produced and commercially popularized at present, comprises DHA oil, ARA oil, EPA oil, DPA oil and the like. The milk produced by cattle and sheep fed with the feed has higher content of functional unsaturated fatty acid. However, since the oleaginous microbial cells contain cell walls, they are difficult to digest and absorb without being decomposed by microorganisms, which affects absorption and utilization of fats and proteins in the cells.

In the process of reinforcing and supplementing grease and protein in the feed, the stomach of the ruminant, which is the inherent characteristic of the digestive system of the ruminant, consists of rumen, reticulum, omasum and abomasum, and special requirements are brought to the supplementing process.

1. And (3) supplementing grease: after the oil supplemented in the feed enters the rumen, the oil is easily decomposed into glycerol and free fatty acid by microorganisms in the rumen, and unsaturated fatty acid in the oil is hydrogenated into saturated fatty acid, so that the supplementing effect of the oil, particularly the oil rich in unsaturated fatty acid, is influenced. Increasing the amount of added fat will affect the digestion of the roughage and affect the palatability of the feed. Therefore, a rumen-protected treatment of supplemented oil is required.

2. Protein supplementation: after entering the rumen, the protein in the feed is decomposed into amino acid by microorganisms in the rumen, and part of the amino acid is further decomposed into ammonia and is discharged and lost. In order to increase the utilization rate of protein in the feed, the supplemented protein needs to be subjected to rumen-bypass protection treatment.

At present, the rumen-bypass protection treatment of ruminant feed is mainly carried out by the following technical methods:

(1) formaldehyde treatment method: the method is widely adopted in the world at present, has a good effect of protecting rumen of fat and protein in the feed, but the negative effect of the method is more and more emphasized because of the influence of problems such as formaldehyde residue and the like.

(2) Hydrogenation treatment method: vegetable oils such as rapeseed oil, cottonseed oil, sunflower seed oil, peanut oil and the like are commonly used as additive oils for feed-fortified oil, and compared with palm oil, the contents of unsaturated oils in the oils are high; the vegetable oil is hydrogenated to improve the saturation of the oil, so that the problem of low utilization rate caused by rumen decomposition when the vegetable oil is added into feed for feeding is avoided. However, the hydrogenation process generates a certain amount of trans-fatty acids, which can migrate into cow milk or goat milk, and has a food safety risk problem, so the method has a certain limitation.

(3) Embedding blood fat powder: animal blood powder is used for embedding, so that the decomposition of grease in rumen is avoided, and the utilization rate of grease and protein in feed is improved, but animal blood has high cost, is easy to introduce infectious diseases and other risks, and is not widely applied.

(4) Fatty acid calcium method: the fat is hydrolyzed and is changed into the fatty acid calcium salt by a chemical conversion method, so that the utilization rate of the feed fat is improved, but the fatty acid calcium salt has the palatability problem and has certain limitation.

The conventional rumen-protected treatment technology has certain defects. Especially, the microbial thallus feed is not decomposed by microorganisms in the rumen after rumen bypass protection, and is difficult to digest and absorb.

Disclosure of Invention

The invention aims to overcome the problem of poor digestion and absorption of microbial thallus feed after rumen protection in the prior art, and provides the feed for improving the milk fat rate of the ruminant, which has the advantages of high oil and protein content, good rumen-bypass protection effect, small nutrient loss and easy digestion and absorption, and can effectively improve the milk fat rate of the ruminant. And the preparation method of the feed has the advantages of simple process, high processing efficiency and good rumen protection effect.

In order to achieve the above objects, the present invention provides, in one aspect, a feed for increasing the milk fat ratio of a ruminant, comprising a core containing microbial cells and a shell containing a peristomal stomach protectant; the microbial thallus is subjected to wall breaking treatment.

Preferably, the core further comprises an embedding wall material, and the embedding wall material comprises a film forming agent, an antioxidant and a filling agent. The film forming agent can enable the microbial thallus with oil after wall breaking treatment to be uniformly dispersed, and oil-containing particles can be better wrapped. The antioxidant is capable of protecting unsaturated fatty acids in the microbial cells from oxidation. The filler enables the core to form a uniform particle.

Preferably, the film forming agent is at least one of sodium caseinate, whey protein powder, modified starch, gum arabic, gelatin, monoglyceride and diglyceride fatty acid ester or citric acid fatty glyceride; further preferably, the film forming agent is at least one of sodium caseinate, whey protein powder, modified starch, acacia, gelatin or mono-diglycerol fatty acid ester; further, the film forming agent is sodium caseinate. The filler is at least one of solid corn syrup, maltodextrin, glucose syrup, glucose monohydrate or lactose; further preferably, the filler is at least one of solid corn syrup, maltodextrin or glucose syrup; further, the bulking agent is maltodextrin. Preferably, the antioxidant is at least one of ascorbyl palmitate, vitamin E, phospholipid, ascorbic acid, sodium ascorbate or potassium ascorbate; further preferably, the antioxidant is at least one of vitamin E, ascorbyl palmitate, sodium ascorbate or potassium ascorbate; further, the antioxidant is vitamin E and ascorbyl palmitate.

Preferably, the feed comprises the following components in parts by weight: 100 parts of microbial thallus, 0.5-10 parts of antioxidant, 1-25 parts of filler, 1-18 parts of film-forming agent and 0.5-20 parts of tumor-treating stomach protective agent.

Preferably, the microbial cells are at least one of Mortierella (Mortierella), ulkenia (Ulkenia), schizochytrium (Schizochytrium), thraustochytriales (Thraustochytriales), and Crypthecodinium cells. The strains are high-yield oil strains, the content of oil in the strains is high, the fat required by the ruminant can be well provided, and the milk yield and the milk fat rate of the ruminant are improved. Meanwhile, the fat synthesized by Mortierella is rich in ARA (arachidonic acid), and the fat synthesized by Ukessella, schizochytrium, thraustochytriales and Crypthecodinium is rich in DHA (docosahexaenoic acid), so that the content of ARA and/or DHA in the milk fat of the ruminant can be correspondingly increased.

Preferably, the cancer-treating agent is shellac, acrylic resin II, acrylic resin III, polyvinyl alcohol acetate phthalate, hydroxypropyl methylcellulose phthalate, opadry or Geum rhinacanthum.

The invention provides a preparation method of a feed for improving the milk fat rate of ruminants in a second aspect, which comprises the following steps: 1) Performing wall breaking treatment on microbial thallus to obtain wall-broken microbial thallus which is used as a nucleus of the feed; 2) And coating the core with a tumor-resistant stomach protectant as a shell to obtain the feed.

Preferably, in the step 1), the microbial cells are at least one of cells of Mortierella, ukenella, schizochytrium, thraustochytriales and Crypthecodinium; the wall breaking treatment is carried out by grinding the microbial thallus to the particle size of 1-10 μm by a sand mill or a homogenizer. The sand mill or homogenizer can destroy the cell wall of the outer layer of the microbial thallus, so that the fat and protein in the thallus can be better digested and absorbed without the participation of microorganisms in the rumen.

Preferably, before the step 2), the crushed microbial cells are added into a solution containing a film-forming agent, an antioxidant and a filler, and the solution is sheared to obtain a microbial liquid, and the microbial liquid is dried to obtain bacterial powder as the core. The film forming agent is at least one of sodium caseinate, whey protein powder, modified starch, acacia, gelatin, monoglyceride and diglycerol fatty acid ester or citric acid fatty glyceride; preferably at least one of sodium caseinate, whey protein powder, modified starch, acacia, gelatin or mono-diglycerol fatty acid ester; more preferably sodium caseinate. The filler is at least one of solid corn syrup, maltodextrin, glucose syrup or dextrose monohydrate; preferably at least one of solid corn syrup, maltodextrin or glucose syrup; further preferably glucose syrup. The antioxidant is at least one of ascorbyl palmitate, vitamin E, phospholipid, ascorbic acid, sodium ascorbate or potassium ascorbate; preferably at least one of vitamin E, ascorbyl palmitate, sodium ascorbate, and potassium ascorbate, and more preferably vitamin E and ascorbyl palmitate. The core comprises the following components in parts by weight: 100 parts of microbial thallus, 0.5-10 parts of antioxidant, 1-25 parts of filler and 1-18 parts of film-forming agent.

Preferably, the rumen protective agent is coated by a fluidized bed or a coating tower, and the dosage of the rumen protective agent is 0.5-20 parts by weight relative to 100 parts by weight of the microbial cells; the tumor-treating and stomach-protecting agent is shellac, acrylic resin II, acrylic resin III, polyvinyl alcohol acetate phthalate, hydroxypropyl methylcellulose phthalate, opadry or Geum rhinacanthum. Compared with the traditional coating method of the tumor-treating stomach protective agent, the tumor-treating stomach protective agent is coated outside the microbial cells by using a fluidized bed or a coating tower, the required temperature condition is low, and the oxidation of oil in the cells, especially unsaturated fatty acid oil in the cells, can be prevented under the high-temperature condition. Meanwhile, the thallus feed formed by coating the tumor-resistant stomach protective agent by using a fluidized bed or a coating tower has more uniform granularity and better coating effect.

Through the technical scheme, the feed for improving the milk fat rate of the ruminant can protect fat and protein in the feed from being damaged by microorganisms in rumen, enables nutrient components in the feed to be easily absorbed, and can effectively improve the milk fat rate of the ruminant. The preparation method of the feed can better produce the feed for improving the milk fat rate of the ruminant, and has the advantages of simple preparation process, high processing efficiency and less loss of nutrient components in the feed.

Detailed Description

The following detailed description of the present invention is provided to illustrate and explain the present invention, and it should be understood that the present invention is not limited to the following detailed description.

Several examples of the preparation method of the feed for increasing the milk fat percentage of ruminants are given below, and the technical effects of the feed for increasing the milk fat percentage of ruminants are verified by performing a cow feeding experiment using the feed for increasing the milk fat percentage of ruminants prepared in the examples. In the specific embodiment, the microbial cells are obtained by self-culture of the company, and the culture method adopts a currently general method; the used equipment and raw materials are all general products purchased from the market.

Example 1

1) The high mountain saturated mold fermentation liquor is filtered by a plate-and-frame filter press to obtain wet thalli, and the water content is 57.8%. 100Kg of wet hirsutella alpina fungi thalli are taken, a sand mill is adopted for wall breaking treatment, zirconium beads are used as grinding media, and the thalli flow out of the sand mill after being ground to obtain bacterial sludge with the grain diameter of 1-10 mu m.

2) Adding maltodextrin 20Kg, sodium caseinate 12Kg, ascorbyl palmitate 1.7Kg, vitamin E0.65kg and water 50Kg into bacterial sludge according to the proportion of adding maltodextrin 20Kg, sodium caseinate 12Kg, ascorbic palmitate 1.7Kg, vitamin E and purified water into 100Kg of wet bacteria, stirring uniformly, and grinding with a sand mill to obtain bacterial liquid.

3) And (3) spray-drying the bacterial liquid prepared in the second step by using a pressure spray dryer, wherein the feeding pressure is 10-18MPa, and the hot air temperature of the dryer is 150-185 ℃, so as to obtain thallus powder.

4) Adding thallus powder into a fluidized bed, taking shellac according to the proportion of adding 10 parts by weight of shellac into 100 parts by weight of wet thallus, dissolving the shellac with water at 80-90 ℃ to prepare a solution with the weight percentage of 20%, and spraying the solution from the first section of the fluidized bed, so that a layer of shellac is coated on the surface of the thallus powder to form a shell of the tumor-treating stomach protectant, and the feed for improving the milk fat rate of the ruminant is obtained.

Example 2

1) Taking 50Kg of hirsutella alpina wet thallus and 50Kg of schizochytrium limacinum wet thallus (filtering schizochytrium limacinum fermentation liquor by using a centrifugal machine), carrying out wall breaking treatment by using a sand mill, grinding zirconium beads as a grinding medium, and enabling the thallus to flow out of the sand mill after grinding to obtain bacterial sludge with the particle size of 1-10 mu m.

2) Adding 18Kg of modified starch, 8Kg of lactose, 7Kg of maltodextrin, 10Kg of sodium ascorbate and 53Kg of water into the bacterial sludge according to the proportion of adding 18Kg of modified starch, 8Kg of lactose, 7Kg of maltodextrin, 10Kg of sodium ascorbate and 53Kg of water into every 100Kg of wet bacterial cells, and homogenizing the bacterial liquid by a high-pressure homogenizer.

3) And (3) drying the bacterial liquid prepared in the second step by using an airflow spray dryer, firstly putting 10kg of maltodextrin into a material trolley of the airflow spray dryer, and obtaining thallus powder at the hot air temperature of 113-135 ℃.

4) Adding thallus powder into a material trolley of a coating drying tower, and adding acrylic resin II as a tumor-treating stomach protective agent according to the proportion of adding 0.5 weight part of acrylic resin II into 100 weight parts of wet thallus. Preparing a protective agent into a solution with the weight percentage of 50%, atomizing the protective agent by using a spray pump, spraying the atomized protective agent into a drying tower, blowing the bacterial powder into a boiling state by hot air in the drying tower from the bottom of the tower, and coating atomized protective agent droplets on the outer surface of bacterial powder particles in a contact manner to obtain the feed for improving the milk fat rate of the ruminants.

Example 3

1) 100Kg of wet bacteria of the wukenchu bacteria are used, a homogenizer is adopted for wall breaking treatment, the homogenizing pressure is 35-62MPa, and the temperature of the feed liquid is kept at 65-72 ℃. Obtaining bacterial sludge with the grain diameter of 1-10 mu m.

2) Adding 1Kg of sodium caseinate, 1Kg of solid corn syrup, 0.5Kg of phospholipid and 55Kg of water into the bacterial sludge according to the proportion of 1Kg of sodium caseinate, 1Kg of solid corn syrup, 0.5Kg of phospholipid and 55Kg of water into 100Kg of wet bacteria, uniformly stirring, and homogenizing by using a high-pressure homogenizer.

3) And drying the bacterial liquid obtained in the second step by using a roller dryer, wherein steam of 0.15-0.25MPa is used during drying, and the temperature of the outer wall of the roller is 110-135 ℃, so that thallus powder is obtained.

4) Taking polyvinyl alcohol acetate phthalate according to the proportion of adding 20 parts by weight of polyvinyl alcohol acetate phthalate to 100 parts by weight of wet thalli, dissolving the polyvinyl alcohol acetate phthalate by using water at 80-90 ℃ to prepare a solution with the weight percentage of 20%, adding the bacterial powder obtained in the step 3) into a fluidized bed, spraying the polyvinyl alcohol acetate phthalate solution from the first section of the fluidized bed, and wrapping a layer of a rumen protective agent shell formed by the polyvinyl alcohol acetate phthalate on the surfaces of the thalli powder to obtain the feed for improving the milk fat rate of the ruminant.

Example 4

1) 100Kg of wet thalli of schizochytrium limacinum are taken, a sand mill is adopted for wall breaking treatment, zirconium beads are used as grinding media, and the thalli flow out of the sand mill after being ground to obtain bacterial sludge with the particle size of 1-10 mu m.

2) Adding 55Kg of water into the bacterial sludge according to the proportion of every 100Kg of wet bacteria, adding purified water into the bacterial sludge, uniformly stirring, and then homogenizing by using a high-pressure homogenizer.

3) And (3) drying the bacterial liquid prepared in the second step by adopting a spray drying method, wherein the feeding pressure is 10-18MPa and the hot air temperature of a dryer is 150-185 ℃ during drying, so as to obtain thallus powder.

4) Taking hydroxypropyl methyl cellulose phthalate according to the proportion of adding 18 parts by weight to 100 parts by weight of wet thalli, and dissolving the hydroxypropyl methyl cellulose phthalate by purified water at the temperature of 80-90 ℃ to prepare a solution with the weight percentage of 20%. Adding the bacterial powder obtained in the step 3) into a fluidized bed, and spraying hydroxypropyl methyl cellulose phthalate solution from the first section of the fluidized bed, so that a layer of the protective agent shell for the stomach cancer formed by hydroxypropyl methyl cellulose phthalate is coated on the surface of the bacterial powder. The feed for improving the milk fat rate of the ruminants is obtained after the second section drying and the third section cooling of the fluidized bed.

Dairy cow raising test

The dairy cattle breeding test was carried out in Laiwu city, shandong province, and 80 Holstein cows with no significant difference in age, number of births, number of lactation days and weight were randomly divided into 4 groups, the first group to the third group were used as experimental groups, and the fourth group was used as a control group.

The specific feeding method comprises the following steps:

1. adjusting period: the whole adjusting period is 20 days, and the cows in each group are fed with 18Kg of the same coarse fodder (silage such as pasture and sugarcane leaves) and 6Kg of the same concentrated fodder (compound fodder such as soybean meal and corn meal) every day. The cows of the first group were fed the feed prepared in example 1 of the present invention; the second group of cows was fed the feed prepared in example 2 of the present invention; a third group of cows was fed the feed prepared in example 3 of the present invention; the fourth group of cows was not fed any other feed.

During the adjustment period, the feed amount of the feed of the present invention (hereinafter referred to as a microbial feed) is gradually increased, that is:

feeding 100g of thallus feed on days 1-3;

feeding 150g of thallus feed on days 4-6;

feeding 200g of thallus feed on 7-9 days;

feeding 250g of thallus feed on 10-12 days;

feeding 300g of thallus feed on days 13-15;

400g of the bacterial feed is fed on the 16 th to 20 th days.

The feeding amount of the cow thallus feed of the three groups is the same.

2. And (3) formal feeding period:

after 20 days of adjustment, entering a formal feeding period, wherein in the whole formal feeding period, each cow of the first group is fed with 18Kg of coarse feed and 6Kg of concentrated feed every day, and simultaneously fed with 0.4Kg of feed prepared by the embodiment 1 of the invention; the second group of cows fed 18Kg of roughage and 6Kg of concentrate per day, while feeding 0.4Kg of the feed prepared in example 2 of the present invention; in the third group, each cow is fed with 18Kg of coarse feed and 6Kg of concentrated feed, and simultaneously fed with 0.4Kg of feed prepared in the embodiment 3 of the invention; the fourth group fed 18Kg of coarse fodder and 6Kg of concentrated fodder to each cow every day without the fodder of the present invention.

In the formal feeding period, 0.4kg of thallus feed is fed every day, and the physicochemical indexes of milk produced by the dairy cows are sampled and detected according to the 10 th day, the 20 th day, the 30 th day, the 40 th day, the 50 th day and the 60 th day in the period.

The results are shown in Table 1.

Table 1: comparison table for milk production condition of dairy cows bred by thalli feed

From the results of table 1, it can be seen that the milk yield of the cows fed with the feed for increasing the butter-fat ratio of ruminants prepared in examples 1 to 3 of the present invention is increased as compared to the control. The milk fat rate in milk is respectively improved by 9.1-18.7%, 12.2-21.5% and 10.5-25.6% compared with the control group (fourth group). The DHA and/or ARA content in the milk produced by the cow fed with the feed processed by the microbial thallus rich in DHA and/or ARA is obviously improved, wherein the DHA content in the milk produced by the cow fed with the microbial thallus feed rich in DHA reaches 11-22.3mg/100mL, and the ARA content in the milk produced by the cow fed with the microbial thallus feed rich in ARA reaches 12.7-28.9mg/100mL. Therefore, the feed for improving the milk fat rate of the ruminants can obviously improve the milk fat rate of the fed ruminants, improve the content of polyunsaturated fatty acid in the milk of the ruminants and improve the nutritional value of milk products.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.

Claims

1. A feed for increasing the milk fat rate of ruminants comprises a core and a shell, wherein the core contains microbial cells, and the shell contains a rumen protective agent; the microbial thallus is subjected to wall breaking treatment, and the tumor-treating stomach protective agent is polyvinyl alcohol acetate phthalate;

the core also comprises an embedding wall material, and the embedding wall material comprises a film forming agent, an antioxidant and a filling agent; the feed comprises the following components in parts by weight: 100 parts of microbial thallus, 0.5-10 parts of antioxidant, 1-25 parts of filler, 1-18 parts of film-forming agent and 0.5-20 parts of tumor-treating stomach protective agent; the microbial thallus is at least one of Mortierella, ugakenella, schizochytrium, thraustochytriales and Crypthecodinium.

2. The feed for increasing the milk fat rate of ruminants according to claim 1, wherein the film-forming agent is at least one of sodium caseinate, whey protein powder, modified starch, gum arabic, gelatin, mono-diglycerol fatty acid ester or citric acid fatty acid glyceride;

the filler is at least one of solid corn syrup, maltodextrin, glucose syrup, glucose monohydrate or lactose;

the antioxidant is at least one of ascorbyl palmitate, vitamin E, phospholipid, ascorbic acid, sodium ascorbate or potassium ascorbate.

3. A method for preparing a feed for increasing the milk fat rate of ruminants according to claim 1 or 2, comprising the steps of:

1) Performing wall breaking treatment on microbial thallus to obtain wall-broken microbial thallus which is used as a nucleus of the feed;

2) Coating the core with a tumor-associated gastric protectant as a shell to obtain the feed;

wherein the tumor-treating and stomach-protecting agent is polyvinyl alcohol acetate phthalate.

4. The method as claimed in claim 3, wherein in the step 1), the cell wall breaking treatment is performed by grinding the microbial cells to a particle size of 1-10 μm using a sand mill or a homogenizer.

5. The method according to claim 3 or 4, wherein before the step 2), the crushed microbial cells are added to a solution containing a film-forming agent, an antioxidant and a filler, and sheared to obtain a microbial liquid, and the microbial liquid is dried to obtain bacterial powder as the core;

the core comprises the following components in parts by weight: 100 parts of microbial thallus, 0.5-10 parts of antioxidant, 1-25 parts of filler and 1-18 parts of film-forming agent.

6. The method according to claim 3 or 4, characterized in that the agent is coated with a fluidized bed or a coating tower, and the agent is used in an amount of 0.5 to 20 parts by weight per 100 parts by weight of the microbial cells.