A method for improving aerobic stability of corn silage

Abstract

The invention discloses a method for improving the aerobic stability of silage corn feed, belongs to the technical field of feed preparation, and is used to solve the technical problem that the aerobic stability of silage corn feed is not high in the prior art. The method for improving the aerobic stability of silage corn feed comprises the following steps: mowing whole silage corn grown to waxy maturity, drying to a moisture content of 65-75%, cutting to 1.5-2.0 cm, and fully mixing to obtain silage raw materials; dissolving bacillus licheniformis in distilled water, and spraying the bacillus licheniformis on the silage raw materials evenly with a spray pot; sealing and packaging the silage raw materials treated with the bacillus licheniformis with an organic film, compacting, loading into a fermentation tank, sealing and fermenting, and obtaining silage corn feed after the fermentation is completed; and the organic film prepared from LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano silicon dioxide has good barrier properties; the silage corn feed prepared by the invention has not only excellent aerobic stability, but also good nutrients.

Description

Technical Field

[0001] The invention relates to the technical field of feed preparation, and in particular to a method for improving the aerobic stability of silage corn feed. Background Art

[0002] Straw is an important output in my country with huge output. Commonly used straw processing methods include fertilizer, feed, fuel, raw material and base material. The utilization of straw as feed is mainly because straw is rich in cellulose, which is an important energy source for ruminants including cattle and sheep. Straw feed includes silage, semi-dry silage, etc. Silage is a method of chopping fresh forage and putting it into a sealed container, and promoting fermentation by microorganisms or additives attached to the raw materials. In an anaerobic environment, the product contains organic acids, which is conducive to antiseptic and antibacterial, thereby achieving a method of extending the shelf life of feed and preserving nutritional value. At present, the quality of silage directly affects the growth and development of animals, the quality of dairy products and the economic benefits of animal husbandry. In particular, silage with better quality can better preserve nutrients, where the preservation of nutrients starts from harvesting and ends when the feed is consumed by animals. The main feature of silage corn is that it reduces its pH value through lactic acid fermentation, inhibits the growth of harmful microorganisms, and retains most of the nutrients, so that it maintains good quality during long-term storage and feeding. It is worth noting that when the aerobic stability is poor, the silage will undergo secondary fermentation and aerobic corruption, which will reduce the utilization value of the silage and cause a large amount of economic losses.

[0003] Chinese patent CN110214852B discloses a fermentation method for corn silage, which includes adding Lactobacillus buchneri and Saccharomyces cerevisiae to the surface layer and Lactobacillus paracasei and Lactobacillus buchneri to the bottom layer during layered fermentation of the silage, so as to improve the aerobic stability of the silage and enhance the quality of the silage; however, the time from opening the silage to starting to heat up is 40.7±2.5h, and the time from starting to heat up to silage deterioration is 10.3±1.4h, so the aerobic stability of the corn silage prepared by this patent needs to be further improved. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for improving the aerobic stability of corn silage, which solves the problem that the aerobic stability of corn silage needs to be further improved at the current stage.

[0005] In order to achieve the above object, the present invention provides a method for improving the aerobic stability of silage corn feed, comprising the following steps:

[0006] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65-75%, cutting it into pieces of 1.5-2.0 cm, and mixing it thoroughly to obtain silage raw material;

[0007] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0008] Step (3) using an organic film to seal and pack the silage raw material obtained in step (2), compact it, put it into a fermentation tank, seal and ferment it, and after the fermentation is completed, obtain silage corn feed;

[0009] Among them, the strain number of Bacillus licheniformis is: CGMCC No.29319;

[0010] The preparation of the organic film includes the following steps:

[0011] S1: adding graphene oxide and p-aminophenol to anhydrous ethanol, adding a catalyst under a nitrogen atmosphere, heating, reacting, filtering, washing, and drying to obtain an intermediate;

[0012] S2: adding the intermediate to anhydrous ethanol, stirring evenly, ultrasonically dispersing, adding tannic acid aqueous solution, stirring, ultrasonically dispersing, filtering, washing, and drying to obtain modified graphene oxide;

[0013] S3: LLDPE, polyvinyl alcohol, modified graphene oxide, and amino-modified nano-silica are melt-blended to obtain a melt, and the melt is prepared into an organic film through a tape casting process.

[0014] Preferably, the mass ratio of Bacillus licheniformis, distilled water and silage raw material is (1-1.2):(4-8):(100-250).

[0015] Preferably, under compaction conditions, the density is 770-830 kg / m 3 .

[0016] Preferably, the viable count of Bacillus licheniformis is 0.8×10 6 CFU / g.

[0017] Preferably, the temperature of the sealed fermentation is 19-21°C; and the sealed fermentation time is 55-65 days.

[0018] Preferably, the mass ratio of graphene oxide, p-aminophenol, anhydrous ethanol and catalyst is (2-4):(80-100):(200-400):(0.06-0.08); the reaction temperature is 90-110°C, and the reaction time is 8-12h; the catalyst is boric acid and N,N,N ， ,N ，- Any of tetramethylpropylenediamine.

[0019] Preferably, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is (1-5):(1000-5000):(200-1400).

[0020] Preferably, the concentration of the tannic acid aqueous solution is 12-20 g / L.

[0021] Preferably, the mass ratio of LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica is (30-50):(50-70):(4-8):(1-3).

[0022] Preferably, the method for preparing amino-modified nano-silicon dioxide comprises the following steps:

[0023] The anhydrous ethanol, nano-silica and 3-aminopropyltriethoxysilane are uniformly mixed and reacted, and after the reaction is completed, the mixture is filtered, washed and dried to obtain amino-modified nano-silica;

[0024] The reaction temperature is 50-75°C and the reaction time is 2-3h;

[0025] Wherein, the mass ratio of anhydrous ethanol, nano-silicon dioxide and 3-aminopropyltriethoxysilane is (3000-6000):(80-120):(30-60).

[0026] Preferably, the temperature of melt blending is 190-210°C.

[0027] Preferably, the tape casting process specifically includes: extruding the melt through a die head and casting it onto a casting roller, and then cooling it through a cooling roller to obtain an organic film;

[0028] The temperature of the die head is 200-220°C, the temperature of the casting roller is 70-90°C, the pulling speed of the casting roller is 7m / min, and the temperature of the cooling roller is 25°C.

[0029] Preferably, the silage corn feed is prepared by the method for improving the aerobic stability of silage corn.

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

[0031] 1. In the present invention, the live bacteria component of Bacillus licheniformis is a dormant spore body, and has the characteristics of high temperature resistance, drying resistance, acid resistance and bile resistance; Bacillus licheniformis is used for sealed fermentation of silage corn, which enhances the decomposition of microorganisms and produces more nutrients and active ingredients, such as reducing sugars, lactic acid and amino acids, and active ingredients such as soluble proteins, phenols, etc., which further improve the digestibility and utilization rate of feed, and enrich the palatability, which is conducive to increasing the food intake of animals. At the same time, the addition of Bacillus licheniformis can regulate the balance of animal microecology, promote the growth of beneficial intestinal bacteria, reduce the number of pathogens, and increase the disease resistance of animal bodies; significantly reduce the odor of ammonia and other odors in the feces of farmed animals and improve the breeding environment. The process of preparing silage corn feed of the present invention is simple and efficient, and significantly improves the aerobic stability of silage corn feed, so that it maintains good quality during long-term storage and feeding.

[0032] 2. In the present invention, graphene oxide is an impermeable flaky filler, which effectively avoids the agglomeration of graphene oxide after modification. The amine group (-NH2) on p-aminophenol and the active carboxyl group (-COOH-) in graphene oxide undergo an amidation reaction to generate a new group amide bond, and the two react to obtain an intermediate. Tannic acid is adsorbed onto the intermediate through π-π interaction to obtain modified graphene oxide, wherein the surface functional group density of the modified graphene oxide increases, the number of hydrogen bonds formed with LLDPE and polyvinyl alcohol increases, the interfacial bonding force between the substrate is enhanced, and the interlayer spacing of the modified filler increases, the dispersibility is better, and the gas molecule permeation path is extended. The amino-modified nano-silica obtained after the modification of nano-silica has good compatibility and dispersibility, and can enhance mechanical properties. Graphene oxide and amino-modified nano-silica synergistically increase the path for oxygen molecules to diffuse in the polymer, which is beneficial to the barrier property of the film, and is beneficial to the sealed fermentation of silage corn, and improves aerobic stability. At the same time, the phenolic hydroxyl groups on the modified graphene oxide have certain reducing properties and can react with oxygen, which is beneficial to reducing the oxygen concentration in a sealed environment and is beneficial to the sealed fermentation in the present invention.

[0033] 3. In the present invention, the addition of graphene oxide improves the mechanical strength and thermal stability of the LLDPE material, making LLDPE easier to handle and shape during processing. The presence of amino-modified nano-silica enhances the dispersibility and uniformity, thereby improving the processing performance of LLDPE. The addition of polyvinyl alcohol makes LLDPE have better fluidity and plasticity during processing, which is convenient for handling and molding. Among them, graphene oxide and amino-modified nano-silica can synergistically increase the barrier properties. The organic film prepared from LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica has excellent barrier properties, which is conducive to better sealing and fermentation of silage raw materials under the action of Bacillus licheniformis. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A flow chart for preparing corn silage feed for the present invention;

[0035] Figure 2 A flow chart for preparing an organic film according to the present invention;

[0036] Figure 3 This is a bar chart showing the aerobic stability test results of corn silage prepared in Example 1 and Comparative Examples 1-3 of the present invention. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0040] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65%, cutting it into pieces of 1.5 cm, and mixing them thoroughly to obtain silage raw materials;

[0041] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0042] Among them, the mass ratio of Bacillus licheniformis, distilled water and silage raw materials is 1:4:100;

[0043] Step (3) The silage raw material obtained in step (2) is sealed and packaged with an organic film at a density of 770 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at a temperature of 19°C for 65 days. After the sealed fermentation is completed, corn silage is obtained.

[0044] The preparation of the organic film includes the following steps:

[0045] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 2:80:200:0.06, stirred, reacted at 90°C for 8h, filtered, washed with deionized water for 3 times, and dried in an oven at 80°C for 6h to obtain an intermediate;

[0046] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 100 r / min for 40 min, ultrasonically dispersing at room temperature and a frequency of 20 kHz for 60 min, adding 12 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 300 r / min for 80 min, ultrasonically dispersing at room temperature and a frequency of 30 kHz for 90 min, filtering, washing with deionized water for 3 times, and drying at 60°C for 8 h to obtain modified graphene oxide;

[0047] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 1:1000:200;

[0048] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder at a mass ratio of 30:50:4:1. The screw speed is 30 r / min and the melt-blending temperature is 190°C to obtain a melt. The melt is extruded through a die head at a temperature of 200°C, and cast onto a casting roll at a temperature of 70°C at a traction speed of 7 m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0049] Example 2

[0050] This embodiment provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0051] Step (1) mowing whole-plant silage corn grown to the waxy stage, airing until the moisture content is 67%, cutting into pieces of 1.6 cm, and mixing thoroughly to obtain silage raw materials;

[0052] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0053] Among them, the mass ratio of Bacillus licheniformis, distilled water and silage raw materials is 1.05:5:137;

[0054] Step (3) The silage raw material obtained in step (2) is sealed and packaged with an organic film at a density of 785 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at a temperature of 19° C. for 62 days. After the sealed fermentation is completed, corn silage is obtained.

[0055] The preparation of the organic film includes the following steps:

[0056] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 2.5:85:250:0.065, stirred, and reacted at 95°C for 11 hours. After the reaction was completed, the mixture was filtered, washed with deionized water for 3 times, and dried in an oven at 85°C for 5.5 hours to obtain an intermediate;

[0057] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 125 r / min for 35 min, ultrasonically dispersing at room temperature and a frequency of 25 kHz for 55 min, adding 18 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 350 r / min for 75 min, ultrasonically dispersing at room temperature and a frequency of 35 kHz for 85 min, filtering, washing with deionized water for 3 times, and drying at 65°C for 7.5 h to obtain modified graphene oxide;

[0058] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 2:2000:500;

[0059] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder in a mass ratio of 35:55:5:1.5. The screw speed is 37 r / min and the melt-blending temperature is 195°C to obtain a melt. The melt is extruded through a die head at a temperature of 205°C, and cast onto a casting roll at a temperature of 75°C at a traction speed of 7m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60μm.

[0060] Example 3

[0061] This embodiment provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0062] Step (1) mowing whole-plant silage corn grown to the waxy stage, airing until the moisture content is 70%, cutting into pieces of 1.7 cm, and mixing thoroughly to obtain silage raw materials;

[0063] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0064] Among them, the mass ratio of Bacillus licheniformis, distilled water and silage raw materials is 1.1:6:175;

[0065] Step (3) The silage raw material obtained in step (2) is sealed and packaged with an organic film at a density of 800 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at 20°C for 60 days. After the sealed fermentation is completed, corn silage is obtained.

[0066] The preparation of the organic film includes the following steps:

[0067] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 3:90:300:0.07, stirred, and reacted at 100°C for 10 hours. After the reaction was completed, the mixture was filtered, washed with deionized water for 3 times, and dried in an oven at 90°C for 5 hours to obtain an intermediate;

[0068] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 150 r / min for 30 min, ultrasonically dispersing at room temperature and a frequency of 30 kHz for 50 min, adding 16 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 400 r / min for 70 min, ultrasonically dispersing at room temperature and a frequency of 40 kHz for 80 min, filtering, washing with deionized water for 3 times, and drying at 70°C for 7 h to obtain modified graphene oxide;

[0069] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 3:3000:800;

[0070] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder at a mass ratio of 40:60:6:2. The screw speed is 45 r / min and the melt-blending temperature is 200°C to obtain a melt. The melt is extruded through a die head at a temperature of 210°C, and cast onto a casting roll at a temperature of 80°C at a traction speed of 7 m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0071] Example 4

[0072] This embodiment provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0073] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 72%, cutting it into pieces of 1.9 cm, and mixing them thoroughly to obtain silage raw materials;

[0074] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0075] Among them, the mass ratio of Bacillus licheniformis, distilled water and silage raw materials is 1.15:7:212;

[0076] Step (3) The silage raw material obtained in step (2) is sealed and packaged with an organic film at a density of 815 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at 21°C for 57 days. After the sealed fermentation is completed, corn silage is obtained.

[0077] The preparation of the organic film includes the following steps:

[0078] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 3.5:95:350:0.075, stirred, and reacted at 105°C for 9 hours. After the reaction was completed, the mixture was filtered, washed with deionized water for 3 times, and dried in an oven at 95°C for 4.5 hours to obtain an intermediate;

[0079] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 175 r / min for 25 min, ultrasonically dispersing at room temperature and a frequency of 35 kHz for 45 min, adding 14 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 450 r / min for 65 min, ultrasonically dispersing at room temperature and a frequency of 45 kHz for 75 min, filtering, washing with deionized water for 3 times, and drying at 75°C for 6.5 h to obtain modified graphene oxide;

[0080] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 4:4000:1100;

[0081] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder in a mass ratio of 45:65:7:2.5. The screw speed is 52 r / min and the melt-blending temperature is 205°C to obtain a melt. The melt is extruded through a die head at a temperature of 215°C, and cast onto a casting roll at a temperature of 85°C at a traction speed of 7 m / min. The melt is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0082] Example 5

[0083] This embodiment provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0084] Step (1) mowing whole-plant silage corn grown to the waxy stage, airing until the moisture content is 75%, cutting into pieces of 2.0 cm, and mixing thoroughly to obtain silage raw materials;

[0085] Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot;

[0086] Among them, the mass ratio of Bacillus licheniformis, distilled water and silage raw materials is 1.2:8:250;

[0087] Step (3) The silage raw material obtained in step (2) is sealed and packaged with an organic film at a density of 830 kg / m 3Compact the corn silage, put it into a fermentation tank, and seal and ferment it at 21°C for 55 days. After the sealed fermentation is completed, corn silage is obtained.

[0088] The preparation of the organic film includes the following steps:

[0089] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 4:100:400:0.08, stirred, and reacted at 110°C for 8 hours. After the reaction was completed, the mixture was filtered, washed with deionized water for 3 times, and dried in an oven at 100°C for 4 hours to obtain an intermediate;

[0090] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 200 r / min for 20 min, ultrasonically dispersing at room temperature and a frequency of 40 kHz for 40 min, adding 12 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 500 r / min for 60 min, ultrasonically dispersing at room temperature and a frequency of 50 kHz for 70 min, filtering, washing with deionized water for 3 times, and drying at 80°C for 6 h to obtain modified graphene oxide;

[0091] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 5:5000:1400;

[0092] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder in a mass ratio of 50:70:8:3. The screw speed is 60 r / min and the melt-blending temperature is 210°C to obtain a melt. The melt is extruded through a die head at a temperature of 220°C, and cast onto a casting roll at a temperature of 90°C at a traction speed of 7 m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0093] Example 6

[0094] This embodiment provides a method for preparing amino-modified nano-silicon dioxide, comprising the following steps:

[0095] Anhydrous ethanol, nano-silica and 3-aminopropyltriethoxysilane were mixed evenly in a mass ratio of 3000:80:30, and reacted at 50°C for 3 hours. After the reaction, the mixture was filtered, washed with deionized water, and dried in an oven at 100°C for 5 hours to obtain amino-modified nano-silica.

[0096] Comparative Example 1

[0097] This comparative example provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0098] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65%, cutting it into pieces of 1.5 cm, and mixing them thoroughly to obtain silage raw materials;

[0099] Step (2) The silage raw material is sealed and packaged with an organic film at a density of 770 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at a temperature of 19°C for 65 days. After the sealed fermentation is completed, corn silage is obtained.

[0100] The preparation of the organic film includes the following steps:

[0101] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 2:80:200:0.06, stirred, reacted at 90°C for 8h, filtered, washed with deionized water for 3 times, and dried in an oven at 80°C for 6h to obtain an intermediate;

[0102] S2: adding the intermediate to anhydrous ethanol, stirring at a speed of 100 r / min for 40 min, ultrasonically dispersing at room temperature and a frequency of 20 kHz for 60 min, adding 12 g / L tannic acid aqueous solution, stirring at room temperature and a speed of 300 r / min for 80 min, ultrasonically dispersing at room temperature and a frequency of 30 kHz for 90 min, filtering, washing with deionized water for 3 times, and drying at 60°C for 8 h to obtain modified graphene oxide;

[0103] Wherein, the mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is 1:1000:200;

[0104] S3: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder at a mass ratio of 30:50:4:1. The screw speed is 30 r / min and the melt-blending temperature is 190°C to obtain a melt. The melt is extruded through a die head at a temperature of 200°C, and cast onto a casting roll at a temperature of 70°C at a traction speed of 7 m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0105] Comparative Example 2

[0106] This comparative example provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0107] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65%, cutting it into pieces of 1.5 cm, and mixing them thoroughly to obtain silage raw materials;

[0108] Step (2) The silage raw material is sealed and packaged with an organic film at a density of 770 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at a temperature of 19°C for 65 days. After the sealed fermentation is completed, corn silage is obtained.

[0109] The preparation of the organic film includes the following steps:

[0110] S1: In a nitrogen atmosphere, graphene oxide, p-aminophenol, anhydrous ethanol and boric acid were mixed in a mass ratio of 2:80:200:0.06, stirred, reacted at 90°C for 8h, filtered, washed with deionized water for 3 times, and dried in an oven at 80°C for 6h to obtain modified graphene oxide;

[0111] S2: LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica are melt-blended in a single-screw extruder at a mass ratio of 30:50:4:1. The screw speed is 30 r / min and the melt-blending temperature is 190°C to obtain a melt. The melt is extruded through a die head at a temperature of 200°C, and cast onto a casting roll at a temperature of 70°C at a traction speed of 7 m / min. It is cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0112] Comparative Example 3

[0113] This comparative example provides a method for improving the aerobic stability of corn silage, comprising the following steps:

[0114] Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65%, cutting it into pieces of 1.5 cm, and mixing them thoroughly to obtain silage raw materials;

[0115] Step (2) The silage raw material is sealed and packaged with an organic film at a density of 770 kg / m 3 Compact the corn silage, put it into a fermentation tank, and seal and ferment it at a temperature of 19°C for 65 days. After the sealed fermentation is completed, corn silage is obtained.

[0116] The preparation of the organic film includes the following steps:

[0117] LLDPE, polyvinyl alcohol, graphene oxide, and amino-modified nano-silica were melt-blended in a single-screw extruder at a mass ratio of 30:50:4:1. The screw speed was 30 r / min, and the melt-blending temperature was 190°C to obtain a melt. The melt was extruded through a die head at a temperature of 200°C, and cast onto a casting roll at a temperature of 70°C at a traction speed of 7 m / min. It was cooled at 25°C through a cooling roll to obtain an organic film with a thickness of 60 μm.

[0118] The amino-modified nano-silica in Examples 1-5 and Comparative Examples 1-3 all adopt the amino-modified nano-silica prepared in Example 6.

[0119] In the examples and comparative examples, the Bacillus licheniformis was from Shandong Zhongke Jiayi Bioengineering Co., Ltd., with a strain number of CGMCC No. 29319 and a total viable count of 1×10 11 CFU / g; whole-plant silage corn was selected from whole-plant silage corn grown to waxy maturity in Ningxia; LLDPE was from Sinopec Yangzi Petrochemical Co., Ltd., brand: DFDA-7042, melt index: 2.2g / 10min, density 0.92g / cm 3 ; Polyvinyl alcohol comes from Tianjin Alfa Aesar Co., Ltd., with a number average molecular weight of 60,000; graphene oxide comes from Beijing Huawei Ruike Chemical Co., Ltd., No.: HWG62234, carbon content ≥99%, state (powder); tannic acid comes from Jiangsu Xiangtai Biotechnology Co., Ltd., item number: 0001368, content 99%; nano-silicon dioxide comes from Shanghai Naio Nano Technology Co., Ltd., with an average particle size of 500 nm; the others are all commercially available products.

[0120] (1) The aerobic stability test and quality evaluation were performed on the corn silage prepared in Example 1 and Comparative Examples 1-3. The aerobic stability test was specifically performed by using an automatic temperature recorder (TOPRIE; instrument model: TP9000; company: Shenzhen Toprie Electronics Co., Ltd.) to measure the temperature of the corn silage prepared in Example 1 and Comparative Examples 1-3, and setting the temperature to be recorded once every 1 hour, repeating each time 3 times, recording the time required for the temperature to rise by 2°C, taking the average value and recording it as the aerobic exposure time; the quality evaluation was performed by evaluating the smell, texture and color of the corn silage when it was just opened; the specific results are shown in Table 1:

[0121] Table 1

[0122]

[0123] As can be seen from Table 1, Comparative Example 1 lacks Bacillus licheniformis compared with Example 1, and its aerobic stability is reduced, the quality of the silage corn feed is reduced, and the silage corn feed prepared in Example 1 is still palatable; Comparative Example 2 lacks the addition of tannic acid compared with Comparative Example 1, and the interface bonding ability of the modified graphene oxide with LLDPE and polyvinyl alcohol is weakened, the dispersibility is reduced, the ability to extend the permeation path of gas molecules is reduced, and the barrier property is reduced, which is not conducive to the sealed fermentation of the silage raw materials under the action of Bacillus licheniformis. Therefore, the aerobic stability is reduced, the aerobic exposure time is reduced, and the quality of the silage corn feed in Comparative Example 2 is lower than that of the silage corn feed prepared in Comparative Example 1; Graphene oxide is not modified, and its dispersibility is naturally reduced. The barrier performance of the organic film prepared by Comparative Example 3 is lower than that of Comparative Example 2, which is not conducive to the sealed fermentation of the silage raw materials under the action of Bacillus licheniformis, so the aerobic stability is deteriorated. Therefore, the quality of the silage corn feed in Comparative Example 3 is lower than that of the silage corn feed prepared in Comparative Example 2.

[0124] (2) The mycotoxin content of the silage corn feed prepared in Example 1 and Comparative Example 1 was tested after opening the can, and the specific test results are shown in Table 2; the mycotoxin content (dry matter basis) of the whole-plant silage corn raw material grown to the waxy stage in Ningxia is specifically shown in Table 3;

[0125] Table 2

[0126]

[0127] Note: Different lowercase letters in the same row indicate significant differences between different fermentation times of the same treatment (P<0.05), and different uppercase letters in the same column indicate significant differences between different treatment groups at the same fermentation time (P<0.05); D (Disposal) indicates treatment, S (Stage) indicates fermentation time, D*S indicates the interaction between treatment and fermentation time, and SEM is standard error.

[0128] Table 3

[0129]

[0130] As shown in Table 2, the mycotoxin content in the corn silage prepared in Comparative Example 1 and Example 1 increased significantly after the can was opened, but the increasing trend of Example 1 was relatively slow during 1-5 days, and the aflatoxin B1 in Example 1 was still significantly lower than the initial raw material recorded in Table 3 after 14 days; the aflatoxin B1 content of the corn silage prepared in Comparative Example 1 was higher than the initial raw material recorded in Table 3 after 14 days. The licheniformis of the corn silage prepared by the present invention can still effectively inhibit the generation of aflatoxin B1 after the can is opened, and can control the production of zearalenone and T-2 toxin in a short period of time, and has the performance of inhibiting the increase of some mycotoxins.

[0131] (3) The mycotoxin content of the corn silage prepared in Example 1 and Comparative Example 1 was tested during the fermentation stage, as shown in Table 4;

[0132] Table 4

[0133]

[0134]

[0135] Combining Table 4 with Table 3 above, it can be seen that the mycotoxin content of Example 1 and Comparative Example 1 decreased significantly during the fermentation process, and the decrease in Example 1 was extremely significant compared with Comparative Example 1, indicating that the microbial additive can effectively reduce the formation of mycotoxins during the fermentation process.

[0136] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that all equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for improving the aerobic stability of corn silage, characterized in that: The following steps are involved: Step (1) mowing whole-plant silage corn grown to the waxy stage, drying it in the sun until the moisture content is 65-75%, cutting it into pieces of 1.5-2.0 cm, and mixing it thoroughly to obtain silage raw material; Step (2) dissolving Bacillus licheniformis in distilled water, and spraying the Bacillus licheniformis evenly on the silage raw material using a spray pot; Step (3) using an organic film to seal and pack the silage raw material obtained in step (2), compact it, put it into a fermentation tank, seal and ferment it, and after the fermentation is completed, obtain silage corn feed; Among them, the strain number of Bacillus licheniformis is: CGMCC No.29319; The preparation of the organic film includes the following steps: S1: adding graphene oxide and p-aminophenol to anhydrous ethanol, adding a catalyst under a nitrogen atmosphere, heating, reacting, filtering, washing, and drying to obtain an intermediate; S2: adding the intermediate to anhydrous ethanol, stirring evenly, ultrasonically dispersing, adding tannic acid aqueous solution, stirring, ultrasonically dispersing, filtering, washing, and drying to obtain modified graphene oxide; S3: LLDPE, polyvinyl alcohol, modified graphene oxide, and amino-modified nano-silica are melt-blended to obtain a melt, and the melt is prepared into an organic film through a tape casting process.

2. A method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The mass ratio of Bacillus licheniformis, distilled water and silage raw materials is (1-1.2):(4-8):(100-250).

3. A method for improving the aerobic stability of corn silage according to claim 1, characterized in that: In compacted conditions, the density is 770-830kg / m 3 .

4. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The viable count of Bacillus licheniformis was 0.8×10 6 CFU / g.

5. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The temperature of sealed fermentation is 19-21℃; the sealed fermentation time is 55-65 days.

6. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The mass ratio of graphene oxide, p-aminophenol, anhydrous ethanol and catalyst is (2-4):(80-100):(200-400):(0.06-0.08); the reaction temperature is 90-110°C, and the reaction time is 8-12h; the catalyst is boric acid and N,N,N ， ,N ， - Any of tetramethylpropylenediamine.

7. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The mass ratio of the intermediate, anhydrous ethanol and tannic acid aqueous solution is (1-5):(1000-5000):(200-1400).

8. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The concentration of the tannic acid aqueous solution is 12-20 g / L.

9. The method for improving the aerobic stability of corn silage according to claim 1, characterized in that: The mass ratio of LLDPE, polyvinyl alcohol, modified graphene oxide and amino-modified nano-silica is (30-50):(50-70):(4-8):(1-3).

10. A corn silage feed prepared by the method for improving the aerobic stability of corn silage according to any one of claims 1 to 9.

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