Processing method of fermented cottonseed meal replacing soybean meal

Abstract

The invention discloses a processing method of fermented cottonseed meal for replacing soybean meal. The method comprises the following steps: uniformly mixing cottonseed meal, feather meal, corn starch and water to obtain a fermentation substrate, adding a first-stage fermentation inoculant into the fermentation substrate for aerobic fermentation, adding a second-stage fermentation inoculant for anaerobic fermentation after fermentation is finished, and performing low-temperature drying and crushing on a fermentation product after fermentation is finished to obtain the cottonseed meal fermented feed. The first-stage fermentation inoculant comprises candida utilis, aspergillus oryzae, papain and cellulase; and the second-stage fermentation inoculant comprises lactobacillus reuteri and lactobacillus acidophilus. According to the method, a bacterium-enzyme synergistic two-step fermentation mode is adopted, bacterium-enzyme synergistic aerobic fermentation is carried out firstly, then anaerobic fermentation is carried out with compound probiotics, and the obtained cottonseed meal fermented feed is high in crude protein and amino acid content and good in palatability, can completely replace soybean meal, can effectively regulate fat metabolism and can improve the lean meat percentage of fattening pigs.

Description

Technical Field

[0001] The invention relates to the technical field of feed fermentation, and in particular to a method for processing fermented cottonseed meal replacing soybean meal. Background Art

[0003] Cottonseed meal is the main source of protein feed for animal farming in my country, but because it contains harmful substances or anti-nutritional factors including cottonpol, it has a negative impact on the growth performance of animals at a high addition, reduces the effective digestion and utilization of nutrients, and even causes animal organ damage. Therefore, reducing the cottonpol content is a key factor in solving the application limitations of cottonseed meal. There have been many studies and progress on the detoxification technology of cottonpol. According to the nature, the detoxification methods can be divided into physical method, chemical method and biological fermentation method. Physical method and chemical method have their own advantages in degrading harmful cottonpol in cottonseed meal, but there are defects such as a large loss of cottonseed meal nutrients and chemical residues. In contrast, the microbial solid fermentation method is to ferment by introducing beneficial microorganisms into the raw materials under suitable conditions, which has low cost, easy operation and high detoxification efficiency. The patents "Effects of Fermented Cottonseed Meal with Composite Probiotics on Growth Performance and Health of Weaned Piglets" (Wang Junyue et al., November 2018, Guangzhou, Guangdong), "Experiment of Fermented Cottonseed Meal to Replace Soybean Meal for Feeding Pigs" (Zhu Xianzhang et al., Feed Industry, Vol. 11, Issue 31, 2010), and Application No. CN201511021332.9 disclose composite bacteria, cottonseed meal fermented feed and its preparation method, etc. These reports all mention the use of composite probiotics to ferment cottonseed meal for use as feed. However, the study found that although there are many microorganisms that can degrade free cottonpol in cottonseed meal at home and abroad, each microorganism has certain limitations in the application of cottonseed meal fermentation. For example, although mold has the ability to degrade cottonpol, its safety in animal feed is still questionable. Bacillus produces irritating ammonia and indole substances in amino acid metabolism, which affects the fermentation flavor, while lactic acid bacteria have poor degradation effect on cottonpol. In addition, in practical applications, the palatability of fermented cottonseed meal is poor, and it can only partially replace soybean meal (up to about 50%), and cannot completely replace soybean meal. Therefore, how to ferment cottonseed meal to overcome the above problems and improve the nutritional content and palatability of fermented cottonseed meal so that fermented cottonseed meal can completely replace soybean meal is a problem that needs to be solved. Summary of the invention

[0004] In view of the above-mentioned prior art, the purpose of the present invention is to provide a method for processing fermented cottonseed meal to replace soybean meal. The present invention adopts a two-step fermentation method of bacterial enzyme synergy, firstly performs aerobic fermentation synergistically with bacterial enzymes, and then performs anaerobic fermentation with composite probiotics. The obtained cottonseed meal fermented feed has high crude protein and amino acid content, good palatability, can completely replace soybean meal, and can also effectively regulate fat metabolism and improve the lean meat rate of fattening pigs.

[0005] To achieve the above object, the present invention adopts the following technical solution: The first aspect of the present invention provides a method for processing fermented cottonseed meal to replace soybean meal, the method comprising: Cottonseed meal, feather meal, corn starch and water are uniformly mixed to obtain a fermentation matrix, a first-stage fermentation agent is added to the fermentation matrix for aerobic fermentation, and after the fermentation is completed, a second-stage fermentation agent is added for anaerobic fermentation, and after the fermentation is completed, the fermentation product is low-temperature dried and crushed to obtain cottonseed meal fermented feed; The first stage fermentation agent includes the following percentages of raw materials: Candida ruanensis 50-70%, Aspergillus oryzae 25-40%, papain 4-10%, cellulase 4-10%; The second stage fermentation agent includes the following percentages of raw materials: Lactobacillus reuteri 60~70%; Lactobacillus acidophilus 30~40%.

[0006] Preferably, the mass ratio of the cottonseed meal, feather meal, corn starch and water is 80-90:10:5:60.

[0007] Preferably, the amount of the first-stage fermentation bacteria agent added accounts for 0.8-1.0% of the total mass of the fermentation substrate; the amount of the second-stage fermentation bacteria agent added accounts for 3-4% of the total mass of the fermentation substrate.

[0008] Preferably, the viable count of the Candida albicans is ≥ 1×10 8 CFU / g; the neutral protease activity of Aspergillus oryzae is ≥1000 U / g; the enzymatic activity of papain is ≥10000 U / g; and the enzymatic activity of cellulase is ≥10000 U / g.

[0009] Preferably, the viable count of Lactobacillus reuteri is ≥ 2×10 9 CFU / g; the viable count of Lactobacillus acidophilus is ≥2×10 9 CFU / g.

[0010] Preferably, the fermentation temperature of the aerobic fermentation is 28-30°C, and the fermentation time is 32-48 h; the fermentation temperature of the anaerobic fermentation is 37-39°C, and the fermentation time is 48-72 h.

[0011] Preferably, the low-temperature drying temperature is 40-45° C., and the low-temperature drying is performed to a moisture content of 10-12%.

[0012] The second aspect of the present invention provides cottonseed meal fermented feed obtained by the above fermentation method.

[0013] The third aspect of the present invention provides the application of the above fermentation method in any one of the following 1) to 4): 1) Increase the crude protein and amino acid content of cottonseed meal fermented feed; 2) Reduce the cottonseed meal fermented feed gossypol content; 3) Increase the content of linolenic acid and ferulic acid in cottonseed meal fermented feed; 4) Reduce the content of phosphatidylethanolamine and phosphatidylcholine in cottonseed meal fermented feed.

[0014] The fourth aspect of the present invention provides the use of cottonseed meal fermented feed in reducing fat deposition and increasing lean meat rate in fattening pigs.

[0015] Beneficial effects of the present invention: (1) The present invention provides a method for processing fermented cottonseed meal to replace soybean meal. By adding an appropriate amount of feather meal to the cottonseed meal, the deficiency of isoleucine and leucine in the cottonseed meal (compared with soybean meal) can be compensated, so that the amino acids in the fermented product are more balanced, the amino acid requirements of animal growth can be met, and the feeding performance of the cottonseed meal can be improved.

[0016] (2) The present invention uses a two-step fermentation method of bacterial enzyme synergistic fermentation to ferment protein raw materials mainly composed of cottonseed meal. After the cottonseed meal is fermented and enzymatically hydrolyzed, the free phenolic and cellulose substances are reduced, the toxicity is reduced, and the palatability is increased. At the same time, the quality of the protein substances in the cottonseed meal is also improved, thereby increasing the utilization rate of the cottonseed meal. During the fermentation process of cottonseed meal, a large amount of aromatic substances such as alcohols and esters are also generated, which can stimulate the sense of smell of animals and attract them to eat.

[0017] (3) The fermentation agent of the present invention is rich in yeast, mold and lactic acid bacteria. During the cottonseed meal fermentation process, multiple bacterial species can compensate for each other's deficiencies and carry out synergistic fermentation. After livestock and poultry ingest the fermented protein feed produced by the method of the present invention, beneficial bacteria will have an absolute advantage, which can regulate the intestinal microbial environment and the colonization sites of pathogenic bacteria, inhibit the growth of other harmful bacteria and pathogenic bacteria, and enhance the body's resistance to disease. DETAILED DESCRIPTION

[0018] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0019] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0020] Description: The cottonseed meal used in the present invention is purchased from Tianli Cotton Industry Co., Ltd. in Huimin County, Shandong Province. It is a byproduct obtained by separating most of the residual oil from the round cakes after cotton seeds are pressed through a leaching process; Feather powder was purchased from Heze Danniu Biological Co., Ltd.

[0021] The test materials used in the examples of the present invention are all conventional test materials in the art and can be purchased through commercial channels.

[0022] Example 85 kg of cottonseed meal, 10 kg of feather meal, 5 kg of corn starch and 60 kg of water were mixed evenly, 1.5 kg of first-stage fermentation agent was added and mixed evenly, and then aerobically cultured at 29°C for 40 hours; after the aerobic fermentation was completed, 5.0 kg of second-stage fermentation agent was added to the fermentation product, mixed evenly, loaded into a fermentation tank, compacted and exhausted, and anaerobically fermented at 38°C for 60 hours to obtain anaerobic fermentation product. The anaerobic fermentation product was low-temperature dried at 42°C until the moisture content was 10-12 wt%, and then crushed to obtain cottonseed meal fermented feed.

[0023] First stage fermentation bacteria: Candida albicans, bacterial count ≥ 1×10 8 CFU / g 60%; Aspergillus oryzae, neutral protease activity ≥1000 U / g 30%; Papain, enzyme activity ≥10000 U / g 5%; Cellulase, enzyme activity ≥10000 U / g 5%; Second stage fermentation agent: Lactobacillus reuteri, bacterial count ≥ 2×10 9 CFU / g 65%; Lactobacillus acidophilus, bacterial count ≥ 2×10 9 CFU / g 35%.

[0024] Comparative Example 1 85 kg of cottonseed meal, 10 kg of feather meal, 5 kg of corn starch and 60 kg of water were mixed evenly, 1.5 kg of primary fermentation agent was added and mixed evenly, and then aerobically cultured at 29°C for 40 hours. The aerobic fermentation product was low-temperature dried at 42°C until the moisture content was 10-12wt%, and then crushed to obtain cottonseed meal fermented feed.

[0025] The first stage fermentation bacterial agent is the same as the first stage fermentation bacterial agent in the embodiment.

[0026] Comparative Example 2 85 kg of cottonseed meal, 10 kg of feather meal, 5 kg of corn starch and 60 kg of water were mixed evenly, 5.0 kg of second-stage fermentation agent was added, mixed evenly, loaded into a fermentation tank, compacted and exhausted, and anaerobically fermented at 38°C for 60 h to obtain an anaerobic fermentation product. The anaerobic fermentation product was low-temperature dried at 42°C until the moisture content was 10-12 wt%, and then crushed to obtain cottonseed meal fermented feed.

[0027] The second-stage fermentation bacterial agent is the same as the second-stage fermentation bacterial agent in the embodiment.

[0028] Comparative Example 3 85 kg of cottonseed meal, 10 kg of feather meal, 5 kg of corn starch and 60 kg of water were mixed evenly, 1.5 kg of first-stage fermentation agent was added and mixed evenly, and then aerobically cultured at 29°C for 40 hours; after the aerobic fermentation was completed, 5.0 kg of second-stage fermentation agent was added to the fermentation product, mixed evenly, loaded into a fermentation tank, compacted and exhausted, and anaerobically fermented at 38°C for 60 hours to obtain anaerobic fermentation product. The anaerobic fermentation product was low-temperature dried at 42°C until the moisture content was 10-12 wt%, and then crushed to obtain cottonseed meal fermented feed.

[0029] First stage fermentation bacteria: Candida albicans, bacterial count ≥ 1×10 8 CFU / g 100%; Second stage fermentation agent: Lactobacillus reuteri, bacterial count ≥ 2×10 9 CFU / g 65%; Lactobacillus acidophilus, bacterial count ≥ 2×10 9 CFU / g 35%.

[0030] Comparative Example 4 85 kg of cottonseed meal, 10 kg of feather meal, 5 kg of corn starch and 60 kg of water were mixed evenly, 6.5 kg of composite bacterial agent was added, and fermented at 37°C for 60 hours. After the fermentation, the fermentation product was low-temperature dried at 42°C until the moisture content was 10-12 wt%, and then crushed to obtain cottonseed meal fermented feed.

[0031] The composite bacterial agent is mixed with Lactobacillus plantarum, Bacillus subtilis, Bacillus licheniformis and Saccharomyces cerevisiae in a mass ratio of 3:2:2:2.

[0032] Comparative Example 5 95 kg of cottonseed meal, 5 kg of corn starch and 60 kg of water were mixed evenly; the remaining steps were the same as those in the embodiment.

[0033] Test Example 1: Component Analysis (1) The nutritional indexes of unfermented cottonseed meal and the cottonseed meal fermented feeds prepared in Examples and Comparative Examples 1 to 5 were tested, and soybean meal was used as a comparison. The results are shown in Table 1.

[0034] Table 1 It can be seen from Table 1 that the crude protein content of the cottonseed meal fermented feed prepared by the present invention is significantly increased, the contents of leucine, isoleucine and lysine are equivalent to those of soybean meal, and the cottonpol content is significantly reduced.

[0035] (2) The metabolites in the unfermented substrate (a mixture of 85 kg cottonseed meal, 10 kg feather meal, 5 kg corn starch, and 60 kg water) and the cottonseed meal fermented feed prepared in the examples were extracted using the acidic methanol-acetonitrile method, and the composition of the extracted metabolites was analyzed using liquid chromatography-tandem mass spectrometry. The partial least squares method-discriminant analysis method was used to perform pattern recognition and search for small molecule differential metabolites. Information on the 7 differential metabolites (substances that have changed, increased or decreased, or newly generated) is shown in Table 2. At the same time, based on these 7 differential metabolites, the relative contents of the 7 metabolites in the cottonseed meal fermented feeds of the examples and comparative examples 1 to 5 were detected and calculated, and the results are shown in Table 3.

[0036] Table 2 The substance related to carbohydrate metabolism in the fermentation metabolites prepared in the embodiment is mannitol, and its relative content is significantly increased compared with that of the unfermented substrate ( P =0.003); compared with the unfermented substrate, the linolenic acid and ferulic acid in the fermentation metabolites prepared in Example were significantly increased ( P <0.001), linolenic acid is an essential fatty acid for animals, and ferulic acid is an aromatic substance. The increase of these two substances can promote animal growth, improve feed flavor, and increase palatability; substances related to protein metabolism include dipeptides and tripeptides, and their relative content is significantly increased compared with unfermented substrates ( P <0.001), the small molecule dipeptides and tripeptides produced by microbial protein decomposition are easier to absorb than single amino acids, and can promote the absorption of amino acids, protein synthesis and deposition, and the absorption and utilization of mineral elements; compared with the unfermented substrate, the phosphatidylethanolamine and phosphatidylcholine related to lipid metabolism in the fermentation metabolites prepared in the embodiment are significantly reduced ( P <0.001), indicating that the microbial fermentation process produced enzymes that promoted the decomposition of phosphatidylethanolamine and phosphatidylcholine, effectively regulating fat metabolism.

[0037] Table 3 Relative content% It can be seen from Table 2 that, except for phosphatidylethanolamine and phosphatidylcholine, no other metabolites in the above table were detected in the unfermented substrate. It can be seen from Table 3 that, compared with other comparative example groups, the content of phosphatidylethanolamine and phosphatidylcholine in the fermentation metabolites prepared in the embodiment is reduced, and the content of other components is increased. The increase in the content of linolenic acid and ferulic acid can improve the appetizing property of the fermented feed and increase the feed intake.

[0038] Test Example 2: Application Test The experiment selected 48 Duroc fattening boars with an initial body weight of (90 ± 1.50) kg and randomly divided them into 2 groups, with 3 replicates in each group and 8 pigs in each replicate. A corn-soybean meal basal diet was prepared according to the nutritional requirements of fattening pigs. The control group fattening pigs were fed with a basic diet, and the experimental group fattening pigs were fed with an experimental diet (the soybean meal in the basic diet was replaced with an equal amount of cottonseed meal fermented feed), wherein the cottonseed meal fermented feed was the cottonseed meal fermented feed prepared in Example or Comparative Examples 1 to 5. The pre-test period was 7 days, and the full test period was 35 days. The basic diet and nutritional level of each group are shown in Table 3.

[0039] Table 3 Basic diet and nutritional level Before the experiment, the initial weight of the fattening pigs was weighed on an empty stomach; after the experiment, the final weight of the fattening pigs was weighed on an empty stomach to calculate the average daily weight gain; the feed intake of the fattening pigs was recorded, and the average daily feed intake and feed-to-weight ratio were calculated respectively. The growth performance indicators are shown in Table 4.

[0040] Table 4 Growth performance As shown in Table 4, compared with the control group, the average daily feed intake of the fattening pigs in the embodiment group increased significantly by 5.78%, the average daily weight gain increased significantly by 11.84%, and the feed-to-weight ratio decreased by 5.41%. This shows that using cottonseed meal fermented feed to replace soybean meal can improve the growth performance of fattening pigs. Since the linolenic acid and ferulic acid contained in comparative examples 1 to 4 are lower than those in the embodiment, the appetizing property of the feed is poor, and the average feed intake decreases. The feed-to-weight ratio of comparative example 5 is slightly lower than that of the control group, indicating that adding feather meal to the fermentation substrate can improve the feed-to-weight ratio of feed intake.

[0041] At the end of the experiment, 12 pigs were selected from each group (4 pigs were randomly selected from each replicate), and they were slaughtered after fasting for 12 hours. Some longissimus dorsi muscle samples were collected and stored in liquid nitrogen for the detection of muscle lipid metabolism related indicators. The results are shown in Table 5.

[0042] Table 5 Effect of the activities of enzymes related to lipid metabolism in the longissimus dorsi muscle of fattening pigs (U / g) As can be seen from Table 5, compared with each comparative example, the ACC and FAS activities of the fattening pigs in the embodiment group were significantly reduced, and the HSL activity was significantly increased. The fat content in pork directly affects the quality of pork, and also has an important impact on the flavor and nutritional value of pork. Studies have shown that ACC, FAS, HSL, etc. all play an important role in lipid metabolism. Although the feed-to-weight ratio of the control group is similar to that of the embodiment group, the weight gain of the control group is more fat; except for the embodiment group, the effect of the comparative example 5 group is basically the same as that of the control group. The ACC and FAS of the embodiment group are lower than those of the control group, and the HSL is increased compared with the control group, indicating that the fermented cottonseed meal prepared in the embodiment can completely replace soybean meal, and the effect of improving pork quality is better than soybean meal. Therefore, the present invention can reduce the activity of ACC and FAS and increase the activity of HSL, indicating that the fermented cottonseed meal feed can reduce fat deposition in fattening pigs and increase lean meat rate by inhibiting fat synthesis and promoting fat decomposition.

[0043] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for processing fermented cottonseed meal to replace soybean meal, characterized in that: The method is: Cottonseed meal, feather meal, corn starch and water are uniformly mixed to obtain a fermentation matrix, a first-stage fermentation agent is added to the fermentation matrix for aerobic fermentation, and after the fermentation is completed, a second-stage fermentation agent is added for anaerobic fermentation, and after the fermentation is completed, the fermentation product is low-temperature dried and crushed to obtain cottonseed meal fermented feed; The first stage fermentation agent includes the following percentages of raw materials: Candida ruanensis 50-70%, Aspergillus oryzae 25-40%, papain 4-10%, cellulase 4-10%; The second stage fermentation agent includes the following percentages of raw materials: Lactobacillus reuteri 60~70%; Lactobacillus acidophilus 30~40%.

2. The fermentation method according to claim 1, characterized in that The mass ratio of the cottonseed meal, feather meal, corn starch and water is 80-90:10:5:

60.

3. The fermentation method according to claim 1, characterized in that The amount of the first-stage fermentation bacteria agent added accounts for 0.8-1.0% of the total mass of the fermentation substrate; the amount of the second-stage fermentation bacteria agent added accounts for 3-4% of the total mass of the fermentation substrate.

4. The fermentation method according to claim 1, characterized in that The viable count of the Candida albicans is ≥ 1×10 8 CFU / g; the neutral protease activity of Aspergillus oryzae is ≥1000 U / g; the enzymatic activity of papain is ≥10000 U / g; and the enzymatic activity of cellulase is ≥10000 U / g.

5. The fermentation method according to claim 1, characterized in that The viable count of Lactobacillus reuteri is ≥ 2×10 9 CFU / g; the viable count of Lactobacillus acidophilus is ≥2×10 9 CFU / g.

6. The fermentation method according to claim 1, characterized in that The fermentation temperature of the aerobic fermentation is 28-30°C, and the fermentation time is 32-48 hours; the fermentation temperature of the anaerobic fermentation is 37-39°C, and the fermentation time is 48-72 hours.

7. The fermentation method according to claim 1, characterized in that The low temperature drying temperature is 40-45° C., and the low temperature drying is performed to a moisture content of 10-12%.

8. Cottonseed meal fermented feed obtained by the fermentation method according to any one of claims 1 to 7.

9. Use of the fermentation method according to any one of claims 1 to 7 in any one of the following 1) to 4): 1) Increase the crude protein and amino acid content of cottonseed meal fermented feed; 2) Reduce the cottonseed meal fermented feed gossypol content; 3) Increase the content of linolenic acid and ferulic acid in cottonseed meal fermented feed; 4) Reduce the content of phosphatidylethanolamine and phosphatidylcholine in cottonseed meal fermented feed.

10. Use of the cottonseed meal fermented feed according to claim 8 in reducing fat deposition and increasing lean meat rate in fattening pigs.

Images