Coffee residue fermented feed composition as well as preparation method and application thereof

Abstract

The invention provides a coffee residue fermented feed composition as well as a preparation method and application thereof. The coffee residue fermented feed composition provided by the invention comprises the following raw materials in parts by weight: 60-89 parts of coffee residues, 5-20 parts of soybean meal, 5-20 parts of wheat bran and 0.5-3 parts of glucose, and aspergillus niger is adopted for fermentation; wherein the inoculum size of the aspergillus niger is 1 * 10 < 5 > / g to 5 * 10 < 6 > / g according to the total weight of the raw materials. The coffee grounds are used as main raw materials for microbial fermentation, a solid state fermentation mode is adopted, and the solid state fermentation process of the coffee grounds is optimized, so that the prepared coffee grounds fermented feed has the advantages that the protein content is obviously increased, various enzymes and antibacterial active substances are contained, and the coffee grounds fermented feed is a green feed product with a medicinal function and a nutritional function; the feed additive can be applied to ruminant feed as an additive or a feed raw material. The goals of improving quality and efficiency, opening sources and increasing feed in animal husbandry are achieved, and technical support is provided for guaranteeing feed raw material supply and stabilizing grain safety.

Description

Technical Field

[0001] The present invention relates to the technical field of fermented feed, and in particular to a coffee grounds fermented feed composition and a preparation method and application thereof. Background Art

[0002] Coffee planting in my country is mainly concentrated in Yunnan, Hainan, Sichuan and other regions, with Yunnan having the highest total output, reaching 113,600 tons. Coffee grounds are a by-product of coffee production, with each ton of coffee beans producing about 650 kg of coffee grounds by-products. A large amount of coffee grounds has caused serious environmental pollution and increased waste disposal costs.

[0003] The direct use of coffee grounds as a by-product has problems such as low digestibility, high moisture content, and easy spoilage. This also limits the application of coffee grounds. At present, the application of coffee grounds is mainly as an additive, adding a small amount to improve the taste of feed. Since coffee grounds themselves have a high fiber content, adding a large amount to the diet of ruminants will lead to problems such as reduced animal feed intake and reduced nutrient digestibility. Therefore, the large-scale utilization of coffee grounds has not been achieved, and the pollution problem of coffee grounds still exists. Summary of the invention

[0004] In order to solve the pollution problem caused by the failure to utilize coffee grounds in large quantities in the prior art, the first aspect of the present invention provides a method for preparing a coffee grounds fermented feed composition, in which coffee grounds are used as the main raw material for microbial fermentation treatment to achieve large-scale effective utilization of coffee grounds and solve the pollution problem of coffee grounds.

[0005] In a first aspect, a method for preparing a coffee grounds fermented feed composition is provided, wherein the raw materials include 60-89 parts of coffee grounds, 5-20 parts of soybean meal, 5-20 parts of wheat bran, and 0.5-3 parts of glucose by weight, and fermentation is carried out using Aspergillus niger; wherein, based on the total weight of the raw materials, the inoculation amount of Aspergillus niger is 1×10 5 / g~5×10 6 Pieces / g.

[0006] The preparation method of the coffee grounds fermented feed composition provided by the present invention uses coffee grounds as the main culture matrix, and obtains the coffee grounds fermented feed through fermentation by Aspergillus niger, thereby realizing the large-scale repeated utilization of coffee grounds, promoting the full utilization of the effective components of the coffee grounds, and effectively solving the pollution problem of coffee grounds. The crude protein content in the feed is also increased, and because the waste coffee grounds are used as the main raw material, the cost is low, and the current domestic aquaculture feed protein resource shortage, high price and other industrial problems are solved.

[0007] In some embodiments, the raw materials include, by weight, 70-850 parts of coffee grounds, 7-15 parts of soybean meal, 7-15 parts of wheat bran, and 1-2 parts of glucose.

[0008] In some embodiments, when fermented by Aspergillus niger, the fermentation temperature is 30-40°C; preferably, the fermentation temperature is 32-38°C.

[0009] In some embodiments, the fermentation time is 4-8 days; preferably, the fermentation time is 5-8 days.

[0010] In some embodiments, the material-liquid ratio of the fermentation is 1:(0.6-1.4); preferably, the material-liquid ratio of the fermentation is 1:(1.0-1.2).

[0011] In a second aspect, a coffee grounds fermented feed composition is provided, which is prepared by the aforementioned preparation method.

[0012] In a third aspect, the invention provides the application of the coffee grounds fermented feed composition as a feed or additive in the field of animal husbandry, for example, as a feed or additive for ruminants, a feed additive for other non-ruminants, etc.

[0013] The present invention uses coffee grounds as the main raw material for microbial fermentation. By optimizing the solid-state fermentation process of coffee grounds, the protein content of the obtained coffee grounds fermented feed is significantly improved, and it contains a variety of enzymes and antibacterial active substances. It is a green feed product with both medicinal and nutritional functions, and can be used as an additive or feed raw material in ruminant feed.

[0014] The method for preparing the fermented coffee grounds feed provided by the present invention can improve the nutritional value of the fermented coffee grounds feed by solid-state fermentation, achieve the goal of improving the quality and efficiency of animal husbandry, and increase the source of feed, and provide technical support for ensuring the supply of feed raw materials and stabilizing food security. The method for preparing the fermented coffee grounds feed provided by the present invention has reference significance for the use of coffee grounds in the fields of animal husbandry and breeding.

[0015] The method for preparing coffee grounds fermented feed provided by the invention effectively reduces the waste disposal cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 This is one of the results of the influence of fermentation time on the crude protein content of coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0018] Figure 2This is one of the results of the influence of fermentation temperature on the crude protein content of coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0019] Figure 3 This is one of the results of the influence of the material-liquid ratio on the crude protein content of coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0020] Figure 4 It is one of the results of the influence of the inoculation amount of Aspergillus niger on the crude protein content of coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0021] Figure 5 It is one of the contour map and response surface map of the influence of the interaction between time and material-liquid ratio on the crude protein content of fermented coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0022] Figure 6 It is one of the contour map and response surface map of the interaction between time and inoculation amount on the crude protein content of fermented coffee grounds in the preparation method of coffee grounds fermented feed provided by the present invention.

[0023] Figure 7 It is one of the contour map and response surface map of the interaction between the inoculation amount and the material-liquid ratio on the crude protein content of the fermented coffee grounds in the preparation method of the coffee grounds fermented feed provided by the present invention. DETAILED DESCRIPTION

[0024] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0025] The study found that the crude protein content of coffee grounds is 11.8%, the crude fat content is 18.0%, and the crude fiber content is 42.5% to 58.0%. In addition, coffee grounds are rich in caffeine, chlorogenic acid, polyphenols, fenugreek and other active substances. It can be seen that coffee grounds are rich in nutrients and can be used as an unconventional feed raw material with high potential utilization value and good application prospects, and can help solve the environmental pollution problem caused by waste coffee grounds.

[0026] The supply and demand of protein feed raw materials in my country are becoming tight, feed costs are high, and the development of new protein feed resources is urgent.

[0027] Studies have found that pre-treating coffee grounds using microbial fermentation technology can improve the digestibility and palatability of coffee grounds to a certain extent, and make them easier to store, but further research on the microbial fermentation of coffee grounds is still needed.

[0028] Based on this, the first aspect of the present invention provides a method for preparing a coffee grounds fermented feed composition, wherein the raw materials include 60-89 parts of coffee grounds, 5-20 parts of soybean meal, 5-20 parts of wheat bran, and 0.5-3 parts of glucose by weight, and fermentation is carried out using Aspergillus niger; wherein, based on the total weight of the raw materials, the inoculation amount of Aspergillus niger is 1×10 5 / g~5×10 6 Preferably, the total amount of the raw materials is 100 parts.

[0029] The preparation method of the coffee grounds fermented feed composition provided by the present invention uses coffee grounds as the main culture matrix, and obtains the coffee grounds fermented feed through fermentation by Aspergillus niger, thereby realizing the large-scale repeated utilization of coffee grounds, promoting the full utilization of the effective components of the coffee grounds, and effectively solving the pollution problem of coffee grounds. The crude protein content in the feed is also increased, and because the waste coffee grounds are used as the main raw material, the cost is low, and the current domestic aquaculture feed protein resource shortage, high price and other industrial problems are solved.

[0030] Based on the total weight of the raw materials, the inoculation amount of Aspergillus niger can be 1×10 5 pcs / g, 3×10 5 pcs / g, 5×10 5 pcs / g, 1×10 6 pcs / g, 3×10 6 pcs / g, 5×10 6 / g or other inoculation amounts within the above range, or a range consisting of these point values, such as 3×10 5 / g~5×10 5 pcs / g, 1×10 6 / g~5×10 6 pcs / g, 1×10 6 / g~3×10 6 pcs / g, 3×10 6 / g~5×10 6 / g, etc., which are not listed here one by one. It has been verified that the inoculation amount is 3×10 6 / g~5×10 6 / g, the crude protein content in the prepared coffee grounds fermentation composition is higher.

[0031] It has been verified that, by weight, the raw materials include 70-85 parts of coffee grounds, 7-15 parts of soybean meal, 7-15 parts of wheat bran, and 1-2 parts of glucose, and the obtained coffee grounds fermented feed composition can obtain a higher crude protein content. Preferably, the total amount of the raw materials is 100 parts.

[0032] In some embodiments, when fermented by Aspergillus niger, the fermentation temperature is 30-40°C. The use of such temperature helps to increase the crude protein content in the coffee grounds fermented feed composition. The fermentation temperature can be 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, or a temperature range composed of these point values, such as 32-36°C, 32-37°C, 34-38°C, 34-36°C, etc., which are not listed here one by one. It has been verified that the fermentation temperature is 32-38°C, and the obtained coffee grounds fermented feed composition can obtain a higher crude protein content.

[0033] In some embodiments, the fermentation time is 4-8 days. The fermentation time can be 4 days, 5 days, 6 days, 7 days, 8 days, or a time range composed thereof, such as 6-8 days, 7-8 days, etc., which are not listed here. It has been verified that the fermentation time is 5-8 days, and the obtained coffee grounds fermented feed composition can obtain a higher crude protein content.

[0034] In some embodiments, the material-liquid ratio of the fermentation is 1:(0.6-1.4). The use of the material-liquid ratio helps to increase the crude protein content in the obtained coffee grounds fermented feed combination. The material-liquid ratio can be 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, or a range of these point values, such as 1:(0.6-1.2), 1:(0.8-1.2), 1:(0.7-1.4), etc., which are not listed here one by one. It has been verified that the material-liquid ratio of the fermentation is 1:(1.0-1.2), and the obtained coffee grounds fermented feed composition can obtain a higher crude protein content. The liquid in the material-liquid ratio is water.

[0035] In some embodiments, the fermentation process is as follows: fermentation time 7 days, inoculation amount 3*10 6 / g, fermentation temperature 32℃, solid-liquid ratio 1:1.2.

[0036] In some embodiments, the fermentation process is as follows: fermentation time 7.40 d, inoculation amount 1.05*10 6 / g, and the solid-liquid ratio was 1:1.04.

[0037] The second aspect provides a coffee grounds fermented feed, which is prepared by the above-mentioned preparation method. The coffee grounds fermented feed has a high crude protein content, which can reach 23.57%.

[0038] The third aspect provides the application of the coffee grounds fermented feed in the animal husbandry field, which can be used as a feed raw material or additive for ruminants; since it has a high fiber content, it can be used as a feed additive for non-ruminants.

[0039] The present invention adopts Aspergillus niger to carry out single fermentation, and its principle is: Aspergillus niger contains almost a full set of decomposition enzymes for botanical raw materials, including amylase, saccharifying enzyme, lipase, protease, cellulase, xylanase, glucanase, mannanase, etc., which can carry out comprehensive and synergistic decomposition of plant raw materials. After the decomposition treatment of plant raw materials, its nutrient components are released in large quantities to provide sufficient and necessary nutrients. It can be seen that it is substantially different from the prior art that Aspergillus niger and yeast are used for mixed fermentation to increase protein content (yeast uses small molecule reducing sugars produced by Aspergillus niger to increase protein content).

[0040] In the examples, information of each raw material is shown in Table 1.

[0041] Table 1 Information on ingredients, sources, etc. of each raw material

[0042] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0043] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0044] Example 1 This embodiment provides a coffee grounds fermented feed for ruminants, and the preparation method thereof comprises: (1) Raw material pretreatment: Wheat bran, soybean meal and coffee grounds were dried at 65°C to constant weight, passed through a 40-mesh sieve, and stored in sample bags at room temperature for later use.

[0045] (2) Inoculation preparation: Select the Aspergillus niger strain from the slant and inoculate it into the PDA slant solid culture medium. Culture it at 37°C for 7 days. Rinse the surface of the culture medium with PBS solution under sterile conditions. Use an inoculation loop to gently scrape the spores on the surface of the culture medium and filter them to make a spore suspension. Store it at 4°C. Calculate the concentration of the spore suspension by the hemocytometer. The obtained spore suspension is used as an inoculum for the fermentation test.

[0046] (3) The substrate for fermentation (coffee grounds, soybean meal, wheat bran, and glucose added in a mass ratio of 80:10:10:1) was placed in a 100 mL Erlenmeyer flask for fermentation, with a total of 10 g of fermentation substrate. The fermentation experiment was set up with 4 replicates and 2 parallel fermentations.

[0047] In this embodiment, the inoculum size of Aspergillus niger is 5*10 5 / g, fermentation time 5 d; fermentation temperature: 32℃; solid-liquid ratio 1:0.8; pH natural.

[0048] Example 2 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that the fermentation time is 4 days during the preparation process.

[0049] Example 3 This embodiment provides a coffee grounds fermented feed, which is basically the same as the embodiment 1, except that the fermentation time is 6 days during the preparation process.

[0050] Example 4 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that the fermentation time is 7 days during the preparation process.

[0051] Example 5 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that the fermentation time is 8 days during the preparation process.

[0052] Example 6 This embodiment provides a coffee grounds fermented feed, which is basically the same as the embodiment 1, except that the fermentation temperature is 30° C. during the preparation process.

[0053] Example 7 This embodiment provides a coffee grounds fermented feed, which is basically the same as the embodiment 1, except that the fermentation temperature is 34° C. during the preparation process.

[0054] Example 8 This embodiment provides a coffee grounds fermented feed, which is basically the same as the embodiment 1, except that the fermentation temperature is 36° C. during the preparation process.

[0055] Example 9 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that the fermentation temperature is 38° C. during the preparation process.

[0056] Example 10 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that during the preparation process, the material-liquid ratio is 1:0.6.

[0057] Embodiment 11 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that during the preparation process, the material-liquid ratio is 1:1.0.

[0058] Example 12 This embodiment provides a coffee grounds fermented feed, which is basically the same as Example 1, except that during the preparation process, the material-liquid ratio is 1:1.2.

[0059] Example 13 This embodiment provides a coffee grounds fermented feed, which is basically the same as the embodiment 1, except that during the preparation process, the material-liquid ratio is 1:1.4.

[0060] Embodiment 14 This embodiment provides a coffee grounds fermented feed, which is basically the same as that of embodiment 1, except that during the preparation process, the inoculation amount of Aspergillus niger is 1×10 5 Pieces / g.

[0061] Embodiment 15 This embodiment provides a coffee grounds fermented feed, which is basically the same as that of embodiment 1, except that during the preparation process, the inoculation amount of Aspergillus niger is 1×10 6 Pieces / g.

[0062] Example 16 This embodiment provides a coffee grounds fermented feed, which is basically the same as that in embodiment 1, the only difference is that during the preparation process, the inoculation amount of Aspergillus niger is 3×10 6 Pieces / g.

[0063] Embodiment 17 This embodiment provides a coffee grounds fermented feed, which is basically the same as that in embodiment 1, the only difference is that during the preparation process, the inoculation amount of Aspergillus niger is 5×10 6 Pieces / g.

[0064] Comparative Example 1 This comparative example provides a fermented coffee grounds feed for ruminants, which is basically the same as Example 1, except that 1% lactic acid bacteria and 1% yeast are used for joint fermentation during its preparation.

[0065] Comparative Example 2 This comparative example provides a fermented coffee grounds feed for ruminants, which is basically the same as Example 1, except that 1% lactic acid bacteria and 10% yeast are used for joint fermentation during its preparation.

[0066] Comparative Example 3 This comparative example provides a fermented coffee grounds feed for ruminants, which is basically the same as Example 1, except that 10% lactic acid bacteria and 1% yeast are used for joint fermentation during its preparation.

[0067] Test Example 1 Determination of dry matter (DM) (water) content Test subjects: Fermented coffee grounds feed provided by Examples 1-17 and Comparative Examples 1-3.

[0068] Test method: Place a clean weighing dish in an oven at 105±2℃ with the lid open for 1 hour, close the lid, take it out, cool it in a desiccator for 30 minutes, and weigh it. Place it in an oven at 105±2℃ with the lid open for 30 minutes, close the lid and cool it, and weigh it until the difference between the two weighings is less than 0.0005 g, which is a constant weight m1.

[0069] Weigh two parallel samples with a constant weight weighing dish, each 2-5 g is recorded as m0. Open the lid and bake in a 105±2℃ oven for 3 h (start timing when the temperature reaches 105℃), close the lid and take out, cool in a desiccator for 30 min, and weigh. Open the lid and dry for 1 h, close the lid and take out, cool in a desiccator for 30 min, and weigh until the difference between the two weighings is less than 0.002 g, which is the constant weight m2.

[0070] Test results: See Table 2.

[0071] Table 2 Results of dry matter (moisture) content

[0072] Test Example 2 Determination of crude protein content in coffee grounds fermented feed Test subjects: Fermented coffee grounds feed obtained in Examples 1-17 and Comparative Examples 1-3.

[0073] Test method: (1) Digestion ① Blank tube: No sample is added to the digestion tube. Only about 2.5 g of mixed catalyst is added, and 10 mL of concentrated sulfuric acid is transferred with a pipette. Repeat for 3 more tubes.

[0074] ② Weigh 0.3 g of the sample and put it into the digestion tube on the digestion rack without loss, and record m; add about 2.5 g of catalyst and use a pipette to transfer 10 mL of concentrated sulfuric acid, and shake gently to soak the sample.

[0075] ③ Digest in the DIGESTOR digestion system until the entire sample becomes a transparent blue-green clear liquid.

[0076] (2) Distillation and titration (on-machine measurement) 1. Blank determination: measure 3 digested blank tubes and calculate based on the lowest value.

[0077] 2. Sample measurement: Place the digested sample tubes in turn, analyze and record the data.

[0078] (3) Calculation of results X: crude protein content in the sample; V: volume of hydrochloric acid standard solution consumed by sample titration; V0: volume of hydrochloric acid standard solution consumed in blank titration; C: concentration of hydrochloric acid standard titration solution; 0.014: The mass of nitrogen equivalent to 1.0 mL of hydrochloric acid (c(HCL)=1.000 mol / L) standard titration solution; 6.25: Nitrogen conversion factor to crude protein in feed.

[0079] m: mass of the sample.

[0080] The final crude protein content (DM basis) was calculated as the percentage of X relative to the dry matter content (X / dry matter content × 100%).

[0081] Test results: see Table 3. The results of crude protein content determination in the coffee grounds fermented feed obtained in Examples 1-5 are as follows Figure 1 As shown; the crude protein content in the coffee grounds fermented feed obtained in Examples 1 and 6-9 is determined as follows Figure 2 As shown; the crude protein content in the coffee grounds fermented feed obtained in Examples 1 and 10-13 is determined as follows Figure 3 As shown; the crude protein content in the coffee grounds fermented feed obtained in Examples 1 and 14-18 is determined as follows Figure 4 shown.

[0082] Table 3 Crude protein content of coffee grounds fermented feed (DM basis)

[0083] From Table 3 and Figure 1 It can be seen that the crude protein content tends to increase with the extension of fermentation time, and the effect is most significant when the fermentation time is 7 days, with a crude protein content of 22.18%.

[0084] From Table 3 and Figure 2 It can be seen that the crude protein content increases first and then decreases with the increase of fermentation temperature. When the fermentation temperature is 32°C, the crude protein content is 20.88%.

[0085] From Table 3 and Figure 3 It can be seen that the crude protein content first increased and then decreased with the increase of the feed-liquid ratio. When the feed-liquid ratio was 1:1.2, the crude protein content was 21.45%, which was significantly higher than that of other groups (P<0.05).

[0086] From Table 3 and Figure 4 It can be seen that the crude protein content increases first and then decreases with the increase of inoculum size. 6 / g, its crude protein content is as high as 22.88%.

[0087] It can be seen from Table 3 that compared with Comparative Examples 1-3, the crude protein content in the coffee grounds fermented feed in Example 1-17 is higher, indicating that the use of Aspergillus niger for fermentation is more conducive to increasing the crude protein content of coffee grounds feed.

[0088] Example 19 Multi-factor response surface design optimization 1. Experimental design and results Based on the single factor experiment, the time (6 d, 7 d, 78 d), inoculation volume (1*10 6 pcs / g, 3*10 6 pcs / g, 5*10 6 The experimental factors (levels) were 1:1.0, 1:1.2, and 1:1.4, respectively. A 3-factor 3-level response surface design was used, with a total of 17 treatments and 3 replicates for each treatment. The crude protein content of the obtained coffee grounds fermented feed was determined, as shown in Table 5.

[0089] Table 4 Factor levels of multi-factor response surface test

[0090] Table 5 Response surface experimental design and results for optimizing crude protein content of coffee grounds

[0091] 2. Response surface test results and regression analysis The results were fitted with a multivariate quadratic response surface using Design-Exper software to obtain the following regression equation: ; Where Y is the crude protein content of fermented coffee grounds, A, B, and C represent time, inoculation amount, and material-liquid ratio, respectively.

[0092] The regression model was analyzed by F test (joint hypothesis test) to test the difference. The test results are shown in Table 6.

[0093] Table 6 Results of variance analysis of the regression model with crude protein content as the evaluation index

[0094] Note: *** in the table indicates extremely significant ( P <0.001); ** is highly significant ( P <0.01); * is significant ( P <0.05).

[0095] As can be seen from Table 6, the optimized model P < 0.001, indicating that the relationship between the multivariate quadratic regression equation of crude protein content and the three factors is significant (P < 0.05); the result of the lack of fit term is not significant (P > 0.05), indicating that the regression model fits the test results well. 2 =0.9726, adjusted determination coefficient R 2 adj=0.9373, indicating that the actual value of crude protein content and the predicted value have a high degree of fit, and the regression model is reliable. The regression coefficient difference analysis results of the quadratic polynomial regression equation of the model: the model linear terms A, B, interaction terms BC, quadratic terms A2 and B2 have significant effects on the results (P < 0.05). From the F value, it can be seen that the influence of each factor on the crude protein content of fermentation is from large to small: A>B>C.

[0096] 3. Interaction of different factors affecting crude protein content of fermented coffee grounds The results of the interaction between time and liquid-to-solid ratio, time and inoculation amount, and inoculation amount and liquid-to-solid ratio on the crude protein content of fermented coffee grounds are shown in Figure 2. Figure 5-7 As shown. Figure 5 It can be seen that the contour lines are circular, which indicates that the interaction between time and material-liquid ratio is not significant. Figure 6 It can be seen that the interaction between time and inoculum amount is not significant. Figure 7 It can be seen that the contour lines are elliptical, which indicates that the inoculation amount and the material-liquid ratio interact significantly (P < 0.05), and it can be seen that the contour lines along the time direction are denser, which indicates that compared with other factors, these results show that the change of time has a more significant effect on the crude protein content of fermented coffee grounds.

[0097] 4. Regression model prediction and verification The regression equation fitted the response surface test of crude protein content in fermented coffee grounds well. The best result obtained by response surface analysis was: time 7.44 d, inoculation size 1.049*10 6 , the material-liquid ratio is 1:1.045, and the predicted value of crude protein content in fermented coffee grounds is 23.779%.

[0098] In order to consider the actual situation and ensure the validity of the total flavonoid content model, at 7.40 days, the inoculation amount was 1.05*10 6The verification test was carried out under the condition of feed-water ratio of 1:1.04, repeated 3 times. The actual value of crude protein content was 23.57%, which was close to the theoretical prediction of the model. It shows that the crude protein content model of fermented coffee grounds optimized by response surface is highly credible. The crude protein content of coffee grounds fermented under the optimal conditions was 17.84% higher than that in the feed composition before optimization (unfermented, coffee grounds, soybean meal, wheat bran, and glucose were directly mixed in a mass ratio of 80:10:10:1, with a total mass of 10g), and the increase rate reached 32.12% (calculation process: (23.57-17.84) / 17.84×100%).

[0099] In summary, the preparation method of the coffee grounds fermented feed composition provided by the present invention can effectively utilize coffee grounds waste with low cost. At the same time, by adopting single fermentation of Aspergillus niger, the composition and ratio of the fermentation substrate are optimized, and the fermentation process is optimized, including the inoculation amount of Aspergillus niger, the fermentation time, the fermentation temperature, the material-liquid ratio, etc., the crude protein content in the coffee grounds fermented feed composition is significantly improved, the nutritional value of the coffee grounds feed is improved, and the current domestic aquaculture feed protein resource shortage, high price and other industrial problems are solved; the invention also contains a variety of enzymes and antibacterial active substances, is a green feed product with both medicinal and nutritional functions, and can be widely used in the field of animal husbandry as an additive or feed raw material.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a coffee grounds fermented feed composition, characterized in that: The raw materials include 60-89 parts of coffee grounds, 5-20 parts of soybean meal, 5-20 parts of wheat bran, and 0.5-3 parts of glucose by weight, and are fermented by using Aspergillus niger; wherein, based on the total weight of the raw materials, the inoculation amount of Aspergillus niger is 1×10 5 / g~5×10 6 Pieces / g.

2. The preparation method according to claim 1, characterized in that: In parts by weight, the raw materials include 70-85 parts of coffee grounds, 7-15 parts of soybean meal, 7-15 parts of wheat bran, and 1-2 parts of glucose.

3. The preparation method according to claim 1 or 2, characterized in that: The fermentation temperature is 30-40°C.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The fermentation temperature is 32-38°C.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The fermentation time is 4-8 days.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The fermentation time is 5-8 days.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The material-liquid ratio of the fermentation is 1:(0.6-1.4).

8. The preparation method according to any one of claims 1 to 6, characterized in that: The material-liquid ratio of the fermentation is 1:(1.0-1.2).

9. A coffee grounds fermented feed composition, characterized in that: The method is prepared by any one of claims 1 to 8.

10. Use of the coffee grounds fermented feed composition according to claim 9 as feed or feed additive in the field of animal husbandry.

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