Preparation method of high-protein animal feed based on fermentation of pericarpium citri reticulatae viride

Abstract

The invention relates to the technical field of animal feed preparation, and discloses a preparation method of a high-protein animal feed based on almond green tangerine peel fermentation. According to the method disclosed by the invention, the badam green tangerine peel and the vinasse are taken as substrates, and the composite flora is added into the substrates for directional fermentation, so that protein enrichment, fiber degradation and functional components are synchronously realized, agricultural wastes such as the badam green tangerine peel and the vinasse are converted into the animal feed with the crude protein content being greater than or equal to 20%, and the production requirements of the low-cost, high-protein and environment-friendly feed are met. In addition, the feed prepared by the preparation method disclosed by the invention can emit mellow, sour and sweet smell, the palatability is remarkably improved, ruminants such as sheep can be stimulated to eat, and the weight gain speed of the sheep is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of animal feed preparation, and particularly to a method for preparing a high-protein animal feed based on the fermentation of almond green peel. Background Art

[0002] Currently, the raw materials of animal feed mainly rely on food crops (such as corn and soybean meal) and traditional protein sources (such as fish meal), but there are problems such as resource competition, high costs, and environmental pressure. The utilization rate of industrial by-products and agricultural waste is insufficient, and the conventional treatment methods mainly involve simple crushing or landfilling, which not only cause waste of resources but also may lead to environmental pollution. For example, almonds ( Prunus dulcis ), also known as almonds, and almond green peel is the green outer pericarp wrapped around the nut, which is usually discarded as an agricultural by-product during the harvesting and processing process. However, research shows that almond green peel is rich in cell wall polysaccharides such as cellulose, hemicellulose, and pectin, and contains polyphenolic antioxidants, volatile aromatic components (such as benzaldehyde and benzyl alcohol), and micronutrients. Currently, the prior art lacks a method for the efficient conversion of almond green peel.

[0003] Existing high-protein feeds rely on the exogenous addition of synthetic amino acids or animal proteins (such as fish meal and meat and bone meal), which have problems such as high costs and the risk of antibiotic residues. Although new raw materials such as insect proteins have been explored, the protein is prone to denaturation during the processing, the oil extraction is not thorough, and there is a lack of a synergistic utilization plan with by-products such as distiller's grains and fruit shells. In addition, the increase in the protein content of traditional feeds often comes at the expense of the fiber degradation rate, resulting in nutritional imbalance.

[0004] Therefore, considering the deficiencies of the existing technology, there is an urgent need for an efficient conversion method using agricultural waste as a substrate to achieve the high-value utilization of agricultural waste. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a method for preparing a high-protein animal feed based on the fermentation of almond green peel.

[0006] The specific technical solution of the present invention is as follows: On the one hand, the present invention provides a method for preparing a high-protein animal feed based on the fermentation of almond green peel, which includes the following steps: (1) Mix distiller's grains and almond green peel in a mass ratio of (1~3):1, and adjust the moisture content to 50wt%~65wt%; (2) Add a compound microbial inoculant and ferment in a sealed state at 20~40°C for 3~7 days; (3) Dry and granulate to obtain an animal feed.

[0007] In the present invention, by using almond green husks and distillers' grains as substrates and adding a composite microbial community for directional fermentation, protein enrichment, fiber degradation, and functional components are simultaneously achieved, realizing the conversion of agricultural waste almond green husks and distillers' grains into animal feed with a crude protein content of ≥20%, meeting the requirements of low-cost, high-protein, and environmentally friendly feed production. In addition, the feed prepared by the preparation method of the present invention can emit a mellow, sour and sweet smell, significantly improving palatability, being able to stimulate the feeding of ruminants such as sheep, and increasing the weight gain rate of sheep.

[0008] As a preference of the above preparation method, the almond green husks are the dried fruit pods obtained after peeling the nut kernels and the fruit shells from almond fruits, and the almond green husks are pulverized materials with a mesh size of 40 - 60.

[0009] As a preference of the above preparation method, the composite microbial inoculant contains at least two of yeast, lactic acid bacteria, bacillus, filamentous fungi, and nitrogen-fixing bacteria.

[0010] As a preference of the above preparation method, the inoculant is composed of Saccharomyces cerevisiae, Candida utilis, Aspergillus niger, Bacillus subtilis, and Lactobacillus plantarum in a mass ratio of (1 - 3):(0.5 - 2):(0.5 - 2):(0.5 - 2):(0.5 - 2).

[0011] As a preference of the above preparation method, during the fermentation process, the initial pH is adjusted to 5.5 - 7.5, and stirring is carried out once every 24 - 48 hours.

[0012] As a preference of the above preparation method, the drying is carried out until the moisture content is below 12 wt%.

[0013] As a preference of the above preparation method, the temperature for sealed fermentation is 25 - 37 °C, and the time is 3 - 5 days.

[0014] As a preference of the above preparation method, the addition amount is 0.5 wt% - 2 wt% of the total mass of the materials.

[0015] On the other hand, based on the above preparation method, the present invention provides a high-protein animal feed.

[0016] Compared with the prior art, the present invention has the following technical effects: 1. In the present invention, by using almond green husks and distillers' grains as substrates and adding a composite microbial community for directional fermentation, protein enrichment, fiber degradation, and functional components are simultaneously achieved, realizing the conversion of agricultural waste almond green husks and distillers' grains into animal feed with a crude protein content of ≥20%, meeting the requirements of low-cost, high-protein, and environmentally friendly feed production. In addition, the feed prepared by the preparation method of the present invention can emit a mellow, sour and sweet smell, significantly improving palatability, being able to stimulate the feeding of ruminants such as sheep, and increasing the weight gain rate of sheep.

[0017] 2. The present invention uses low-value distillers' grains and almond green husks as the main raw materials, without the need to additionally add conventional feed raw materials such as grains and soybean meal, realizing "turning waste into treasure" and reducing feed costs.

[0018] 3. Through the transformation of this method, the environmental pollution caused by distillers' grains and pod wastes can be reduced, which conforms to the concept of green circular economy. Detailed implementation manners

[0019] The present invention will be further described below in conjunction with embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only a part of the embodiments of the present invention, rather than all the embodiments. Therefore, all other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0020] In one embodiment, a method for preparing a high-protein animal feed based on the fermentation of almond green husks is provided, which includes the following steps: (1) Mix distillers' grains and almond green husks in a mass ratio of (1~3):1, and adjust the moisture content to 50wt%~65wt%; (2) Add a compound microbial inoculant and ferment in a sealed state at 20~40°C for 3~7 days; (3) Dry and granulate to obtain an animal feed.

[0021] In this embodiment, by using almond green husks and distillers' grains as substrates, adding a compound microbial community for directional fermentation, simultaneously realizing protein enrichment, fiber degradation and functional components, and realizing the conversion of agricultural wastes almond green husks and distillers' grains into an animal feed with a crude protein content of ≥20%, meeting the feed production requirements of low cost, high protein and environmental protection. In addition, the feed prepared by the preparation method of this embodiment can emit a mellow, sour and sweet smell, significantly improving the palatability, being able to stimulate the feeding of ruminants such as sheep, and increasing the weight gain rate of sheep.

[0022] In one embodiment, as a preference of the above preparation method, the almond green husks are the dried fruit pods obtained after peeling the almond kernels and fruit shells from almond fruits, and the almond green husks are pulverized materials with a mesh size of 40~60.

[0023] In one embodiment, as a preference of the above preparation method, the compound microbial inoculant contains at least two of yeast, lactic acid bacteria, bacillus, filamentous fungi and nitrogen-fixing bacteria.

[0024] In one embodiment, as an optimization of the above preparation method, the microbial agent is composed of Saccharomyces cerevisiae, Candida utilis, Aspergillus niger, Bacillus subtilis and Lactobacillus plantarum in a mass ratio of (1 - 3):(0.5 - 2):(0.5 - 2):(0.5 - 2):(0.5 - 2).

[0025] In one embodiment, as an optimization of the above preparation method, during the fermentation process, the initial pH is adjusted to 5.5 - 7.5, and stirring is carried out once every 24 - 48 hours.

[0026] In one embodiment, as an optimization of the above preparation method, the drying is carried out until the water content is below 12 wt%.

[0027] In one embodiment, as an optimization of the above preparation method, the temperature for sealed fermentation is 25 - 37 °C, and the time is 3 - 5 days.

[0028] In one embodiment, as an optimization of the above preparation method, the addition amount is 0.5 wt% - 2 wt% of the total mass of the materials.

[0029] Example 1 Preparation of Distillers Grains - Prunus dulcis Peel Solid Fermentation Feed (1) Raw material preparation: Take 50 kg of fresh distillers grains from white liquor (wet basis, water content about 65%, crude protein content about 18%) and 25 kg of dried and pulverized Prunus dulcis peel. The distillers grains are naturally drained until the water content is about 55%, and then mixed evenly with the Prunus dulcis peel powder. The initial crude protein content of the mixture is about 15%, and the crude fiber content is about 18%.

[0030] (2) Microbial agent preparation: The composite microbial agent is made by mixing Saccharomyces cerevisiae, Candida utilis, Aspergillus niger, Bacillus subtilis and Lactobacillus plantarum in a mass ratio of 2:1:1:1:1, and about 10 7 CFU / g of Azotobacter vinelandii (preserved by culturing with calcium acetate) is added. The total viable count of the microbial agent is about 2×10 8 CFU / g.

[0031] (3) Fermentation: The above composite microbial agent is inoculated into the mixed raw materials at an addition amount of 1% (mass ratio), that is, the dosage of the microbial agent is about 0.75 kg. After mixing evenly, the materials are loaded into a fermentation barrel and compacted, and a breathable plastic film is covered to maintain a micro - aerobic state. The fermentation barrel is placed in a constant temperature environment at 30 °C for 4 days. When the fermentation reaches the 2nd day and the 3rd day, the barrel lid is opened to stir the materials once each to ensure uniform fermentation and release gas, and then the lid is re - sealed to continue fermentation. At the end of the 4th day, a sample is taken and smelled, with a mellow and sour aroma and no putrid smell.

[0032] (4) Post-treatment: Take out the fermented materials and spread them on a clean plastic sheet, and dry them in the sun for 2 days to reduce the moisture content to about 10%. Then slightly crush the dried materials with a pulverizer to obtain the finished fermented feed.

[0033] (5) Detection: Take the mixed raw materials before fermentation and the finished feed after fermentation respectively and send them to the laboratory for analysis of the main nutritional components. The results are listed in Table 1. It can be seen that the crude protein content of the feed after fermentation increased from the original 15.2% to 26.5%, an increase of 74%; the crude fiber decreased from 18.3% to 12.0%, a decrease of 34%. The contents of crude fat and crude ash changed slightly (possibly due to microbial synthesis and mineral concentration). The fermentation product was weakly acidic (pH about 5.6), containing about 1.2% lactic acid, which could play a role in natural preservation. By sensory observation, the fermented feed was in the form of dark brown loose powder, emitting the fragrance of koji and fruit, and there was no mildew.

[0034] Table 1 Comparison of the contents of main nutritional components of feed before and after fermentation (calculated based on dry matter) Project Mixed raw materials before fermentation Finished feed after fermentation Moisture (%) 55.0 9.8 Crude protein (%) 15.2 26.5 Crude fiber (%) 18.3 12.0 Crude fat (%) 4.7 5.1 Crude ash (%) 6.5 7.0 Lactic acid (%) 0 1.2 pH value 6.8 5.6 The above results show that through the fermentation process of the present invention, the nutritional value of distiller's grains and almond green peels has been significantly improved. Table 1 shows that after fermentation treatment, the crude protein of the feed increased significantly, the crude fiber decreased significantly, and a certain amount of organic acid was produced, which was beneficial to feed preservation and animal digestion.

[0035] Example 2 (1) Raw material preparation: Take 50 kg of fresh beer distiller's grains (wet basis with a water content of about 67% and a crude protein content of about 20%) and 25 kg of dried and pulverized almond green peels. Naturally drain the distiller's grains until the water content is about 55%, and mix them evenly with the almond green peel powder. The initial crude protein content of the mixture is about 16%, and the crude fiber content is about 18%.

[0036] (2) Strain preparation: The compound microbial inoculant is prepared by mixing Saccharomyces cerevisiae, Candida utilis, Aspergillus niger, Bacillus subtilis and Lactobacillus plantarum in a mass ratio of 2:1:1:1:1, and adding about 10 7 CFU / g of Azotobacter vinelandii (preserved by culturing with calcium acetate). The total viable count of the inoculant is about 2×10 8 CFU / g.

[0037] (3)Fermentation: The above-mentioned compound bacterial agent was inoculated into the mixed raw materials at an addition amount of 1% (mass ratio), that is, the dosage of the bacterial agent was about 0.75 kg. After mixing evenly, the materials were put into a fermentation barrel and compacted, and then covered with a breathable plastic film to maintain a micro-oxygen state. The fermentation barrel was placed in a constant temperature environment of 30 °C for 4 days. On the 2nd and 3rd days of fermentation, the barrel lid was opened to stir the materials once each to ensure uniform fermentation and release gas, and then the lid was resealed to continue fermentation. At the end of the 4th day, a sample was taken and smelled. There was a mellow sour aroma and no putrid odor.

[0038] (4)Post-treatment: The fermented materials were taken out and spread on a clean plastic cloth, and dried in the sun for 2 days to reduce the moisture content to about 10%. Then the dried materials were slightly pulverized by a pulverizer to obtain the finished fermented feed.

[0039] Example 3 Effect test of fermented feed on Dorper sheep (1)Experimental design: 40 healthy weaned Dorper sheep lambs were selected and randomly divided into a control group and an experimental group, with 20 lambs in each group. Both groups of sheep were fed a basal diet (composed of corn, hay, etc.). Among them, in the experimental group, the fermented feed prepared in Example 1 or Example 2 was used to replace 20% of the concentrate part in the basal diet (based on the principle of equal nitrogen replacement). The control group was replaced with an equal amount of conventional protein supplement (a mixture of cottonseed meal and soybean meal). The experimental period was 60 days, with a 7-day adaptation period. During the whole experimental process, both groups had free access to clean drinking water. The feed intake and weight gain of each sheep were recorded, and the health status of the flock was monitored.

[0040] (2)Results: At the end of the experiment, the average weight of the sheep in the experimental group increased from the initial 20.5 kg to 35.2 kg, and that of the control group increased from 20.3 kg to 33.1 kg. The average daily weight gain of the experimental group was about 13.3% higher than that of the control group (247 g / d in the experimental group and 218 g / d in the control group). The daily feed intakes of the two groups were similar, but the amount of feed consumed per 1 kg weight gain in the experimental group was about 8% less than that in the control group. In terms of the health of the flock, no obvious digestive problems such as diarrhea were observed in the experimental group, while 2 sheep in the control group had slight loose stools. The serum biochemical indexes of the two groups of sheep were basically normal, but the metabolic indexes such as alanine aminotransferase and urea nitrogen in the experimental group were slightly better than those in the control group, indicating a lower metabolic burden on the liver and kidneys. Table 2 summarizes the main production performance indexes.

[0041] Table 2 Effects of fermented feed added with Example 1 or Example 2 on the growth performance of Dorper sheep Index Control group (conventional diet) Experimental group 1 (fermented feed diet of Example 1) Experimental group 2 (fermented feed diet of Example 2) Daily weight gain (g / day) 218 ± 15 247 ± 12 229 ± 11 Feed consumption per 1 kg weight gain (kg) 5.2 4.8 (improvement) 5.0 (improvement) Incidence of diarrhea 10%(2 / 20) 0% (0 / 20) 0% (0 / 20) Average daily feed intake (kg / day) 1.35 1.40 1.37 The data in Table 2 show that adding the fermented feed of the present invention to the diet can improve the weight gain rate of Dorper sheep, reduce the feed conversion and consumption, and is more beneficial to growth and feed utilization than the control group. In addition, no diarrhea cases occurred in the experimental group, indicating that the fermented feed has a positive effect on intestinal health.

[0042] The feeding experiment in Example 2 confirmed that the fermented high-protein feed prepared by the present invention, when applied to the diet of Dorper sheep, can effectively improve the growth performance and feed utilization efficiency, and contribute to maintaining the intestinal health of the flock. This further illustrates that the fermented feed produced by the method of the present invention has good application value and popularization prospects in actual breeding.

[0043] In summary, as can be seen from the above examples, the method provided by the present invention can efficiently convert by-products such as distiller's grains and almond green peels into high-protein feed under antibiotic-free conditions, and significantly improve the production performance and health status of ruminants (such as Dorper sheep).

[0044] (3)The comparative experiment between Example 1 and Example 2 showed that the animal feed prepared with almond green peels and liquor distiller's grains as substrates had a better production effect on Dorper sheep, while the beer distiller's grains were slightly inferior.

[0045] The raw materials and equipment used in the present invention are all common raw materials and equipment in the art without special instructions; the methods used in the present invention are all conventional methods in the art without special instructions.

[0046] The above are only the preferred embodiments of the present invention, and do not limit the present invention in any way. Any simple modifications, changes, and equivalent transformations made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of a high-protein animal feed based on the fermentation of almond green peel, characterized in that: It includes the following steps: (1) Mix distillers grains and almond green peels at a mass ratio of (1~3):1, and adjust the moisture content to 50wt%~65wt%; (2) Add a compound microbial inoculant and ferment in a sealed state at 20~40°C for 3~7 days; (3) Dry and granulate to obtain the high-protein animal feed.

2. The preparation method according to claim 1, characterized in that: The distillers grains are liquor-distilled distillers grains; the almond green peels are the dried fruit pods obtained after removing the nut kernels and the fruit shells from almond fruits, and the almond green peels are pulverized materials with a mesh size of 40~60.

3. The preparation method according to claim 1, characterized in that: The compound microbial inoculant contains at least two of yeast, lactic acid bacteria, bacillus, filamentous fungi, and nitrogen-fixing bacteria.

4. The preparation method according to claim 3, characterized in that: The inoculant is composed of Saccharomyces cerevisiae, Candida utilis, Aspergillus niger, Bacillus subtilis, and Lactobacillus plantarum at a mass ratio of (1~3):(0.5~2):(0.5~2):(0.5~2):(0.5~2).

5. The preparation method according to claim 1, characterized in that: During the fermentation process, adjust the initial pH to 5.5~7.5 and stir once every 24~48 hours.

6. The preparation method according to claim 1, wherein: The drying is to dry to a moisture content of less than 12wt%.

7. The preparation method according to claim 1, characterized in that: The temperature of the sealed fermentation is 25~37°C and the time is 3~5 days.

8. The preparation method according to claim 1, characterized in that: The addition amount of the compound microbial inoculant is: add 0.5wt%~2wt% of the total mass of the materials.

9. The high-protein animal feed prepared by the preparation method according to any one of claims 1~8.