Processing method of edible mushroom dregs and application thereof

Abstract

The application discloses a processing method of edible mushroom dregs and application thereof. The processing method comprises the following steps: crushing edible mushroom dregs to obtain dreg particles; performing extrusion and puffing treatment on the dreg particles by using a double-screw extruder to obtain puffed materials; drying and crushing the puffed materials to obtain puffed dreg powder; mixing the puffed dreg powder, bean dregs and cellulase as a fermentation substrate, adding mixed bacteria liquid to the fermentation substrate to form a fermentation mixed liquid; the mixed bacteria liquid is formed by mixing Candida utilis bacteria liquid, Lactobacillus plantarum bacteria liquid and Bacillus subtilis bacteria liquid; and performing fermentation on the fermentation mixed liquid under aeration condition to obtain a final edible mushroom dreg product. Compared with a traditional processing method, the crude protein content, acid-soluble protein content and protein dispersion index of the edible mushroom dregs processed by the processing method are significantly improved, and the contents of crude fiber, neutral detergent fiber and acid detergent fiber are significantly reduced.

Description

Technical Field

[0001] This application relates to the field of agricultural waste resource utilization technology, specifically to a processing method for edible fungus residue and its application. Background Technology

[0002] With the rapid development of my country's animal husbandry and feed industry, the demand for high-quality protein feed resources continues to rise. According to statistics from the Animal Husbandry and Veterinary Bureau of the Ministry of Agriculture and Rural Affairs, my country's livestock industry consumed 117 million tons of protein feed in 2022, of which 75.04 million tons were imported, accounting for 64.1%. In 2023, the total protein consumed by my country's livestock industry was 81.45 million tons, of which 37.03 million tons were imported, accounting for 45.5%. The shortage of high-quality protein raw materials is a prominent issue and has become a key bottleneck restricting the sustainable development of the livestock industry.

[0003] Mushroom residue, a solid byproduct of edible mushroom cultivation, is rich in residual microbial protein. It is produced in large quantities at low prices and has good potential for feed application. The crude protein content in mushroom residue is generally 8%–15%, significantly higher than that of straw (3%–5%). Under certain conditions, it can replace some soybean meal as a protein supplement. my country's annual production of mushroom residue exceeds 40 million tons. If it can be effectively converted into feed resources, it will significantly alleviate the shortage of protein feed, reduce feed costs, and decrease environmental pollution.

[0004] As a specialty edible mushroom variety promoted in recent years, the annual yield of its by-product, mushroom substrate (Lyophyllum decastes), has increased rapidly. For every kilogram of fresh mushrooms produced, 3-5 kilograms of substrate are produced, containing a high proportion of lignocellulose (60%-70%) and residual mycelial protein (8%-12%). Although it has high protein potential, its dense fiber structure and high lignin content mean that direct consumption as feed without treatment leads to low digestibility, poor palatability, and unsatisfactory feeding results.

[0005] In existing technologies, the feed utilization of bacterial residue mainly employs microbial fermentation, which degrades fiber and improves palatability and protein content through microbial metabolism. However, single fermentation methods suffer from technical problems such as insufficient pretreatment capacity, incomplete breakdown of substrate structure, and low fermentation efficiency, affecting the release and conversion efficiency of nutrients.

[0006] Therefore, there is an urgent need to develop a method to improve the feed value and bioconversion efficiency of edible fungi residue. Summary of the Invention

[0007] In view of this, the purpose of this application is to provide a processing method for edible fungus residue and its application. This processing method adopts a physical-biological synergistic approach, namely, extrusion puffing and solid-state fermentation to synergistically process edible fungus residue, thereby achieving deep modification of the structure of edible fungus residue and bioaccumulation of nutrients, significantly improving its utilization value in monogastric animal feed.

[0008] To achieve the above objectives, this application provides the following technical solution:

[0009] In a first aspect, this application provides a method for processing edible mushroom substrate, comprising the following steps:

[0010] S1. Crush the edible mushroom residue to a particle size of less than 2mm to obtain mushroom residue granules;

[0011] S2. The mushroom husk granules are extruded and expanded using a twin-screw extruder to obtain the expanded material;

[0012] S3. Dry and pulverize the puffed material, and pass it through a 40-mesh sieve to obtain puffed mushroom bran powder;

[0013] S4. Mix the puffed bacterial bran powder and soybean residue evenly to form a mixture, add cellulase to the mixture to form a fermentation substrate, and then add the mixed bacterial solution to the fermentation substrate to form a fermentation mixture; the mixed bacterial solution is formed by mixing Candida utilis solution, Lactobacillus plantarum solution and Bacillus subtilis solution;

[0014] S5. Ferment the fermentation mixture under aeration to obtain the final edible mushroom substrate product.

[0015] Through the above technical solutions, the synergistic effect of extrusion puffing pretreatment and solid-state fermentation with compound microbial agents can effectively overcome the efficiency bottleneck of single treatment methods on lignocellulose in edible mushroom substrate and increase the protein content of edible mushroom substrate.

[0016] Based on the above technical solutions, further optimization of process conditions can lead to some preferred technical solutions, resulting in higher quality edible mushroom substrate products.

[0017] In some embodiments, in S1, the mushroom substrate is *Pleurotus ostreatus* substrate. For every kilogram of fresh mushrooms produced, 3-5 kilograms of substrate are produced as a byproduct, containing a high proportion of lignocellulose (60%-70%) and residual mycelial protein (8%-12%), indicating high protein potential.

[0018] In some embodiments, in S2, the twin-screw extruder is configured with the following conditions: feeding zone 60–100°C, compression zone 90–130°C, extrusion zone 120–160°C, screw speed 100–300 rpm, die diameter 5–7 mm, and extrusion chamber pressure maintained at 0.5–2.0 MPa. Through the extrusion puffing process in S2, the lignocellulose structure in the edible fungus substrate is disrupted, and the material is homogeneously puffed.

[0019] In some preferred embodiments, in S2, the twin-screw extruder is set to a temperature of 80°C in the feeding zone, 110°C in the compression zone, 140°C in the extrusion zone, and a screw speed of 200 rpm.

[0020] In some embodiments, in S3, the moisture content of the dried puffed material is less than 15%.

[0021] In some embodiments, in S4, the mass ratio of the puffed bacterial bran powder to soybean residue is 9:1.

[0022] In some embodiments, in S4, the mixed bacterial solution consists of 5 × 10 5 CFU / mL Candida utilis culture, 2×10 7 CFU / mL Lactobacillus plantarum bacterial culture and 5×10 5 The CFU / mL Bacillus subtilis bacterial solution is mixed at a volume ratio of 1-3:70-90:7-29, and the inoculation amount of the mixed bacterial solution is 10% of the mass of the fermentation substrate; the cellulase is 10 IU / kg of fermentation substrate.

[0023] In some preferred embodiments, in S4, the mixed volume of the Candida utilis culture, Lactobacillus plantarum culture, and Bacillus subtilis culture is 2:80:18.

[0024] In some implementation schemes, the specific steps of S5 are as follows: after the fermentation mixture obtained in S4 is mixed evenly, it is put into a respirable fermentation bag, compacted, degassed and sealed, and placed at a constant temperature of 37°C for 5 days for fermentation. The aeration rate is set to 0.3 vvm. During the fermentation process, the pile is turned over once every 12 hours, and finally the fermented edible fungus bran product is obtained.

[0025] Secondly, this application provides the application of the aforementioned processing method in the preparation of monogastric animal feed.

[0026] The edible mushroom residue prepared by the aforementioned processing method has a crude protein content of 21.73%–23.25%, crude fiber degradation to 17.54%–18.72%, acid-soluble protein content increased to 5.63%–8.16%, and a protein dispersion index (PDI) of 32.48–36.91. This significantly improves the protein solubility and digestibility of the feed, and animal experiments have verified its efficient application in monogastric animal feed systems. The fermented edible mushroom residue obtained through the aforementioned processing method can be directly added to the feed formulations of fattening pigs and laying hens, with an appropriate addition amount of approximately 10% of the feed weight.

[0027] Compared with the prior art, this application has at least the following advantages:

[0028] 1. This application effectively overcomes the efficiency bottleneck of single biological treatment for lignocellulose degradation by combining extrusion puffing pretreatment with solid-state fermentation of compound microbial agents. This results in an increase in crude protein content of *Pleurotus ostreatus* fungus residue to 23.25% (58.6% higher than single fermentation process), crude fiber degradation to 17.54% (46.9% lower than untreated raw material), and acid-soluble protein content to 8.16% (292% higher than untreated raw material), significantly improving feed protein solubility (protein dispersion index reaches 36.91).

[0029] 2. Animal experiments have verified that when the mushroom bran prepared in this application is added to the diet of fattening pigs at a mass fraction of 10%, it can maintain an average daily weight gain of 662.05 g / day (no significant difference from the conventional feed group of 686.26 g / day, P>0.05), achieving a feed conversion ratio of 2.05 and increasing gross profit by 0.02 yuan / kg, demonstrating excellent production performance. When added to the diet of 40-week-old laying hens at a mass fraction of 15%, the egg production rate at weeks 41-44 and 45-48 reached 92.6% and 93.0%, respectively (better than the conventional feed group of 92.3% and 92.5%, no significant difference, P>0.05), with a feed conversion ratio of 2.11 and significantly improved egg quality, increasing gross profit by 0.17 yuan / kg, achieving the dual benefits of agricultural waste resource utilization and feed cost reduction. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application.

[0031] Those skilled in the art will understand that, unless otherwise stated, the terms "the," "the," and "the foregoing" used in this application may also include plural forms. It should be further understood that the word "comprising" as used in the specification of this application means the presence of the stated features, steps, or operations, but does not exclude the presence or addition of one or more other features, integers, or steps.

[0032] Those skilled in the art will understand that, where specific experimental steps or conditions are not specified in the embodiments, they can be performed according to the conventional experimental steps or conditions described in the literature in this field; and where the manufacturers of the raw materials or instruments and equipment used are not specified, they are all conventional products that can be obtained commercially.

[0033] Those skilled in the art will understand that, unless otherwise stated in this application, when numerical ranges are given in the embodiments, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application, as well as the prior art known to those skilled in the art and the descriptions in this application, can be implemented using any prior art methods, devices, and materials similar to or equivalent to those described, used, or made by means of methods, devices, and materials in the embodiments of this application.

[0034] The following detailed embodiments illustrate the technical solution of this application and the technical effects achieved. The specific experimental scheme is as follows:

[0035] 1. Main materials and reagents

[0036] Raw materials for edible mushroom substrate: mushroom substrate for deer antler mushrooms. The main components of the substrate are sugarcane bagasse, corn cob, corn flour, wheat bran and light calcium.

[0037] Soybean dregs: Purchased from a local soybean product processing plant, crushed and passed through a 40-mesh sieve, with moisture content controlled below 14%.

[0038] Microbial strains: Candida utilis (CICC32722), Lactobacillus plantarum (CICC22703) and Bacillus subtilis (CICC10732) were all purchased from the China Industrial Microbial Culture Collection Center (CICC).

[0039] Culture media: MRS medium, purchased from Qingdao Haibo Biotechnology Co., Ltd.; YPD medium, self-prepared: 20 g / L peptone, 10 g / L yeast extract, 20 g / L glucose; LB medium, self-prepared: 10 g / L tryptone, 5 g / L yeast extract, 10 g / L NaCl.

[0040] 2. Detection Indicators and Methods

[0041] Crude protein (CP) in mushroom residue: Detected according to GB / T 6432-2018 Determination of crude protein in feed - Kjeldahl method;

[0042] Crude fiber (CF): The content of crude fiber in feed was determined according to GB / T 6434-2006, Filtration method.

[0043] Neutral detergent fiber (NDF): Tested according to GB / T 20806-2022 Determination of neutral detergent fiber (NDF) in feed;

[0044] Acid detergent fiber (ADF): Tested according to "NY / T 1459-2022 Determination of acid detergent fiber in feed";

[0045] Acid-soluble protein content (ASP): Tested according to "NY / T 3801-2020 Determination of acid-soluble protein in feed ingredients";

[0046] Protein Dispersion Index (PDI): Detected according to the method specified in AOCS Standard Procedure Ba 10b-09.

[0047] Example 1

[0048] This embodiment provides a method for processing edible mushroom bran, the specific steps of which are as follows:

[0049] S1. Pretreatment of mushroom residue:

[0050] Using a high-moisture raw material pulverizer (Zhigao II type, Shanghai Chungu), the mold-free deer antler mushroom substrate (moisture content 20%~50%) was crushed into substrate particles with a particle size not exceeding 2mm. Random samples were taken for nutrient composition determination (three parallel samples, average value was taken).

[0051] S2. Extrusion and puffing of mushroom residue:

[0052] The mushroom husk granules were extruded and expanded using a twin-screw extruder to obtain expanded material. The twin-screw extruder was configured with the following conditions: feeding zone 60°C, compression zone 90°C, extrusion zone 120°C, screw speed 100 rpm, die diameter 6 mm, and extrusion chamber pressure maintained at 1.0 MPa.

[0053] S3. Drying and pulverizing the mushroom residue:

[0054] The puffed material obtained in S2 was dried using a steam tube dryer (MGZG type, Myander) until the moisture content did not exceed 15%. After cooling to 30°C, it was pulverized using a high-fiber raw material pulverizer (XG68ZJ type, Shanghai Chungu) and passed through a 40-mesh sieve to obtain puffed bacterial bran powder. Random samples were taken for nutrient composition determination (three parallel samples, average value).

[0055] S4. Preparation of fermentation mixture with fungal residue:

[0056] First, the puffed bacterial bran powder obtained from S3 was mixed with soybean residue at a mass ratio of 9:1. Simultaneously, 10 IU / kg cellulase was added to this mixture and mixed thoroughly to prepare the bacterial bran fermentation substrate. Second, a mixed bacterial solution was prepared: *Candida utilis* was inoculated into YPD medium and cultured at 30℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 5 × 10⁻⁶. 5 CFU / mL was used to obtain Candida utilis seed culture; Lactobacillus plantarum was inoculated into MRS medium and cultured at 37℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 2×10⁻⁶. 7 CFU / mL was used to obtain Lactobacillus plantarum seed culture; Bacillus subtilis was inoculated into LB medium and cultured at 37℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 5 × 10⁻⁶ CFU / mL. 6 CFU / mL was used to obtain Bacillus subtilis seed culture; Candida utilis culture, Lactobacillus plantarum culture, and Bacillus subtilis culture were mixed at a volume ratio of 2:80:18 to obtain mixed culture culture; finally, 10% of the mass of the fermentation substrate was added to the mixed culture culture to obtain the fermentation substrate mixture.

[0057] S5. Fermentation process:

[0058] After the fermentation mixture of mushroom residue obtained in step S4 is mixed evenly, it is put into a breathing fermentation bag, compacted, degassed and sealed, and placed in a constant temperature room at 37℃ for 5 days for fermentation. The aeration rate is set to 0.3vvm. During the fermentation process, the pile is turned over once every 12 hours, and finally the fermented mushroom residue sample K1 of antler mushroom is obtained.

[0059] Example 2

[0060] This embodiment provides a processing method for edible mushroom bran. The specific steps differ from those in Embodiment 1 in that: in S2, the temperatures of the three temperature zones of the twin-screw extruder are 80°C in the feeding zone, 110°C in the compression zone, and 140°C in the extrusion zone, and the screw speed is 200 rpm; other conditions and parameters are the same, and a sample K2 of mushroom bran for antler mushrooms is obtained.

[0061] Example 3

[0062] This embodiment provides a method for processing edible mushroom bran. The specific steps differ from those in Embodiment 1 in that: in S2, the temperatures of the three temperature zones of the twin-screw extruder are 100°C in the feeding zone, 130°C in the compression zone, and 160°C in the extrusion zone, and the screw speed is 300 rpm; other conditions and parameters are the same, and a sample K3 of mushroom bran is obtained.

[0063] Example 4

[0064] This embodiment provides a method for processing edible mushroom residue. The specific steps differ from those in Embodiment 1 in that: in S2, the temperatures of the three temperature zones of the twin-screw extruder are 80°C in the feeding zone, 110°C in the compression zone, and 140°C in the extrusion zone, and the screw speed is 200 rpm; in S4, the mass ratio of Candida utilis culture, Lactobacillus plantarum culture, and Bacillus subtilis culture in the mixed bacterial solution is 1:70:29; other conditions and parameters are the same, and the mushroom residue sample K4 of Mushroom Reishi mushroom is obtained.

[0065] Example 5

[0066] This embodiment provides a method for processing edible mushroom residue. The specific steps differ from those in Embodiment 1 in that: in S2, the temperatures of the three temperature zones of the twin-screw extruder are 80°C in the feeding zone, 110°C in the compression zone, and 140°C in the extrusion zone, and the screw speed is 200 rpm; in S4, the mass ratio of Candida utilis culture, Lactobacillus plantarum culture, and Bacillus subtilis culture in the mixed bacterial solution is 3:90:7; other conditions and parameters are the same, and the mushroom residue sample K5 of Mushroom Reishi mushroom is obtained.

[0067] Comparative Example 1

[0068] This comparative example provides a method for processing edible mushroom bran. Compared with Example 1, this processing method eliminates the step of extruding and puffing the mushroom bran from *Agaricus esculentus*. The specific steps are as follows:

[0069] (1) Pretreatment of mushroom residue

[0070] The mold-free deer antler mushroom substrate (moisture content 20%-50%) was crushed into substrate particles with a particle size not exceeding 3mm using a high-moisture raw material pulverizer (Zhigao II type, Shanghai Chungu). Random samples were taken for nutrient composition determination (three parallel samples, average value).

[0071] (2) Drying and pulverizing the mushroom residue

[0072] The mushroom residue granules were dried using a steam tube dryer (MGZG type, Myander) until the moisture content did not exceed 15%. After cooling to 30°C, they were pulverized using a high-fiber raw material pulverizer (XG68ZJ type, Shanghai Chungu) and passed through a 40-mesh sieve to obtain mushroom residue powder. Random samples were taken for nutrient composition determination (three parallel samples, average value).

[0073] (3) Preparation of fermentation mixture of fungal bran

[0074] First, the bacterial bran powder obtained in (2) was mixed with soybean residue at a mass ratio of 9:1. At the same time, 10 IU / kg cellulase was added to the mixture and mixed evenly to prepare the bacterial bran fermentation substrate. Second, the mixed bacterial solution was prepared: Candida utilis was inoculated into YPD medium and cultured at 30℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 5 × 10⁻⁶. 5 CFU / mL was used to obtain Candida utilis seed culture; Lactobacillus plantarum was inoculated into MRS medium and cultured at 37℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 2×10⁻⁶. 7 CFU / mL was used to obtain Lactobacillus plantarum seed culture; Bacillus subtilis was inoculated into LB medium and cultured at 37℃ and 200 rpm for 24 h. After two generations of continuous culture, the concentration was adjusted to 5 × 10⁻⁶ CFU / mL. 6 CFU / mL was used to obtain Bacillus subtilis seed culture; Candida utilis culture, Lactobacillus plantarum culture, and Bacillus subtilis culture were mixed at a volume ratio of 2:80:18 to obtain mixed culture culture; finally, 10% of the mass of the fermentation substrate was added to the mixed culture culture to obtain the fermentation substrate mixture.

[0075] (4) Fermentation process

[0076] After the fermentation mixture of mushroom residue obtained in step S4 is mixed evenly, it is put into a breathing fermentation bag, compacted, degassed and sealed, and placed in a constant temperature room at 37℃ for 5 days for fermentation. The aeration rate is set to 0.3 vvm. During the fermentation process, the pile is turned over once every 12 hours, and finally the fermented mushroom residue sample K6 is obtained.

[0077] Comparative Example 2

[0078] This comparative example provides a processing method for edible mushroom bran. Compared with Example 2, this processing method omits the fermentation process of the mushroom bran raw material, that is, it only includes steps S1-S3 of Example 2. The specific steps are as follows:

[0079] S1. Pretreatment of substrate residue

[0080] The mold-free deer antler mushroom substrate (moisture content 20%-50%) was crushed into substrate particles with a particle size not exceeding 3mm using a high-moisture raw material pulverizer (Zhigao II type, Shanghai Chungu). Random samples were taken for nutrient composition determination (three parallel samples, average value).

[0081] S2. Extrusion and puffing of mushroom residue

[0082] The mushroom bran granules were extruded and expanded using a twin-screw extruder to obtain expanded material. The twin-screw extruder was configured with the following conditions: feeding zone 80°C, compression zone 110°C, extrusion zone 120°C, screw speed 200 rpm, die diameter 6 mm, and extrusion chamber pressure maintained at 1.0 MPa.

[0083] S3. Drying and pulverizing the mushroom residue:

[0084] The puffed material obtained in S2 was dried using a steam tube dryer (MGZG type, Myander) until the moisture content did not exceed 15%. After cooling to 30°C, it was pulverized using a high-fiber raw material pulverizer (XG68ZJ type, Shanghai Chungu) and passed through a 40-mesh sieve to obtain puffed mushroom residue powder, which is the processed mushroom residue sample K7 of velvet mushroom. The nutritional components were randomly sampled for analysis (three parallel samples, average value).

[0085] Comparative Example 3

[0086] This comparative example provides a processing method for edible mushroom residue. Compared with Example 2, in this processing method S4, only Candida utilis liquid (i.e., using pure Candida utilis liquid instead of mixed liquid) is used for fermentation. Other conditions and parameters are the same as in Example 2, and antler mushroom residue sample K8 is obtained.

[0087] Comparative Example 4

[0088] This comparative example provides a processing method for edible mushroom residue. Compared with Example 2, in this processing method S4, only Lactobacillus plantarum liquid (i.e., using pure Lactobacillus plantarum liquid instead of mixed liquid) is used for fermentation. Other conditions and parameters are the same as in Example 2, and antler mushroom residue sample K9 is obtained.

[0089] Comparative Example 5

[0090] This comparative example provides a processing method for edible mushroom residue. Compared with Example 2, in this processing method S4, only Bacillus subtilis bacterial solution (i.e., using pure Bacillus subtilis bacterial solution instead of mixed bacterial solution) is used for fermentation. Other conditions and parameters are the same as in Example 2, and antler mushroom residue sample K10 is obtained.

[0091] Comparative Example 6

[0092] The raw material of the purchased mushroom substrate was used as the mushroom substrate sample K11, which had not undergone extrusion puffing and solid-state fermentation processing.

[0093] Table 1 below compares the key parameters in Examples 1-5 and Comparative Examples 1-6:

[0094] Table 1

[0095]

[0096] Result verification:

[0097] The contents of crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid-soluble protein (ASP), and protein dispersion index (PDI) in the mushroom substrate samples K1 to K11 prepared in the above examples and comparative examples were detected. The detection results are shown in Table 2 below.

[0098] Table 2

[0099]

[0100]

[0101] In the examples and comparative examples, the treatment methods for the mushroom substrate included extrusion puffing + mixed strain solid-state fermentation synergistic process (Examples 1-5), single solid-state fermentation process (Comparative Example 1), single extrusion puffing treatment (Comparative Example 2), extrusion puffing + single strain treatment (Comparative Examples 3-5), and no treatment (Comparative Example 6). As can be seen from the test results in Table 2, the extrusion puffing + mixed microbial solid-state fermentation synergistic process provided in this application has a significantly better effect on treating the mushroom substrate of *Ichthyophthirius multiflora* than the other four treatment methods. Specifically, in the mushroom substrate samples treated by the extrusion puffing + mixed microbial solid-state fermentation synergistic process in the examples: (1) The crude protein content was significantly increased, with an average crude protein content of 20.8% and a maximum of 23.25% (Example 3). Compared with Comparative Examples 1 to 6, the maximum increases were 58.5%, 196.6%, 83.9%, 186.3%, 117.1%, and 191.4%, respectively; (2) The crude fiber content was significantly decreased, with an average fiber content of 19.6% and a minimum of 17.54% (Example 4). Compared with Comparative Examples 1 to 6, The maximum values ​​decreased by 24.7%, 45.9%, 38.9%, 39.7%, 28.7%, and 46.8%, respectively; (3) The protein dispersion index was significantly improved, with an average value of 35.19 and a maximum value of 36.91 (Example 2), which was better than Comparative Example 1. Compared with Comparative Examples 2 to 6, the maximum values ​​increased by 348.5%, 162.1%, 114.1%, 57.9%, and 251.5%, respectively; (4) Other indicators, such as the content of neutral detergent fiber (average value 48.36%, minimum value 41.92%) and acid detergent fiber (average value 39.52%, minimum value 34.63%), were significantly reduced, while the content of acid-soluble protein (average value 7%, maximum value 8.16%) was significantly increased. It can be seen that the processing method of edible fungus bran provided in this application significantly improves the conversion efficiency of edible fungus bran compared with traditional processing methods.

[0102] Comparing the results of Examples 1-5, it can be found that in Example 2, the optimal overall treatment effect was achieved when the extrusion conditions of the twin-screw extruder were set as follows: feeding zone 80°C, compression zone 110°C, extrusion zone 140°C, and screw 200 rpm. This was combined with a compound inoculant containing Candida utilis, Lactobacillus plantarum, and Bacillus subtilis (volume ratio 2:80:18).

[0103] Analysis of the results from Comparative Examples 1-6 revealed that the absence of extrusion puffing (Comparative Example 1), single solid-state fermentation (Comparative Example 2), or treatment without compound microbial agents (Comparative Examples 3-5) all failed to simultaneously achieve the dual technical objectives of efficient fiber degradation and deep protein enrichment (improving crude protein, acid-soluble protein, and protein dispersion index). Therefore, the edible mushroom residue processing method provided in this application achieves high conversion efficiency of edible mushroom residue due to the synergistic effect of extrusion puffing and mixed-culture solid-state fermentation.

[0104] The effect of treated mushroom residue in feed preparation

[0105] Application Example 1

[0106] Twenty Duroc-Landrace-Large White crossbred finishing pigs weighing 22.57±1.47 kg were randomly assigned to four treatment groups (one control group + three control groups) using a single-factor design. Each treatment group included five replicates, with one pig per replicate. The *Deer Antler Mushroom* mycelium residue (hereinafter referred to as "fermented mycelium residue"), processed using the aforementioned extrusion and mixed-culture solid-state fermentation process, was used as the feed ingredient for the growing-finishing pigs. The basal diet for the pigs was formulated according to the NRC2012 nutritional requirements for pigs, replacing different amounts of wheat bran. The control group used the basal diet formula as a reference. Group I received 5% fermented mycelium residue by weight of feed, Group II received 10% fermented mycelium residue by weight of feed, and Group III received 15% fermented mycelium residue by weight of feed. Detailed formulations for the four treatment groups are shown in Table 3. Automatic water supply was provided using duckbill drinkers. The pigsty was regularly cleaned and disinfected. The pre-feeding period was one week, and the formal experimental period was 21 days. The effect of the treated edible mushroom residue as a feed additive on the growth performance of finishing pigs was investigated.

[0107] Table 3

[0108] corn 58.98 58.94 58.37 56.23 Fermented yeast bran 0 5 10 15 soybean meal 16.43 16.2 16.62 15.46 wheat bran 10.87 6.4 1.43 0 Soy protein concentrate 7.5 7.5 7.5 7.5 soybean oil 1.83 1.49 1.59 1.29 salt 0.31 0.31 0.31 0.31 stone powder 1.21 1.15 1.11 1.09 Calcium hydrogen phosphate 1.48 1.59 1.63 1.64 Lysine 0.15 0.17 0.18 0.21 Methionine 0.24 0.25 0.26 0.27 premix 1 1 1 1 total 100 100 100 100 Nutritional level Digestible energy MJ / kg 13.58 13.58 13.58 13.58 crude protein 17.70 17.70 17.70 17.70 Lysine 1.05 1.05 1.05 1.05 Methionine 0.50 0.50 0.51 0.51 Methionine + Cystine 0.54 0.53 0.53 0.53 calcium 0.90 0.90 0.90 0.90 Available phosphorus 0.40 0.40 0.40 0.40

[0109] The test results are shown in Table 4 below, where a, b, and c are indicators of significant differences.

[0110] Table 4

[0111] Average daily weight gain (g / day) <![CDATA[686.26±87.42 a ]]> <![CDATA[675.41±48.74 a ]]> <![CDATA[662.05±35.27 a ]]> <![CDATA[592.18±74.26 b ]]> Average daily feed intake (g / day) 1393.11±110.72 1404.85±137.08 1357.2±54.13 1409.39±131.25 Average material weight ratio (g / day) <![CDATA[2.03±0.13 b ]]> <![CDATA[2.08±0.08 b ]]> <![CDATA[2.05±0.12 b ]]> <![CDATA[2.38±0.20 a ]]> Daily food price (yuan / kg) 3.12 3.08 3.08 3.01 Live pig price (yuan / kg) 14.50 14.50 14.50 14.50 Cost of weight gain feed (RMB / kg) 6.33 6.40 6.31 7.23 Gross profit per kilogram (RMB / kg) 8.17 8.10 8.19 7.27

[0112] As shown in Table 4, the average daily weight gain of pigs fed with 10% fermented bran as an additive (Experimental Group II) was 662.05 g / day, which was not significantly different from the control group (686.26 g / day) (P>0.05). The feed conversion ratio remained at 2.05, which was at the same level as the control group and the 5% additive group (Experimental Group I) (P>0.05). When the amount of fermented bran added increased to 15% (Experimental Group III), the average daily weight gain decreased significantly to 592.18 g / day (P<0.05), and the feed conversion ratio increased to 2.38. The average daily feed intake of each experimental group ranged from 1357.2 to 1409.39 g / day, which was not significantly different from the control group. The daily feed price for fattening pigs using fermented bran at mass fractions of 5%, 10%, and 15% decreased from RMB 3.12 / kg to RMB 3.08, 3.08, and 3.01 / kg, respectively. Among them, the weight gain cost of the 10% group decreased from RMB 6.33 / kg in the control group to RMB 6.31 / kg, and the gross profit per kilogram of weight gain increased from RMB 8.17 / kg in the control group to RMB 8.19 / kg.

[0113] Application Example 2

[0114] One hundred and eight 40-week-old Jingfen No. 1 laying hens were randomly divided into three treatment groups, with 12 replicates per treatment and 28 hens per replicate. Deer antler mushroom bran (hereinafter referred to as "fermented bran"), processed using the aforementioned extrusion and mixed-culture solid-state fermentation process, was used as a feed ingredient to replace different amounts of corn alcohol residues and soluble matter. The basal diet was formulated according to the nutritional requirements in the Jingfen No. 1 feeding management manual. The control group used the basal diet formula. Experimental group I received 5% fermented bran by weight of feed, experimental group II received 10% fermented bran by weight of feed, and experimental group III received 15% fermented bran by weight of feed. Before the experiment, the egg production rate of each group was adjusted to be consistent. The basal diet was used for one week of pre-feeding, and the formal experimental period was eight weeks. During the experiment, the accurate daily feed intake of the hens in each replicate was recorded, and the egg production rate, average daily feed intake, and feed conversion ratio were calculated. In week 8, five eggs (n=50) were selected from each replicate, for a total of 150 eggs, for egg quality testing. The detailed formulations for the four treatment groups are shown in Table 5. The effects of the treated edible fungus residue as a feed additive on the laying hen production performance were investigated.

[0115] Table 5

[0116]

[0117]

[0118] The test results are shown in Table 6, where a, b, and c are indicators of significant differences.

[0119] Table 6

[0120] 41-44 weeks Egg production rate (%) 92.3±4.2 91.8±2.0 92.6±3.1 91.4±2.7 Average daily feed intake (grams / day) 99.5±8.4 99.2±8.9 99.9±7.2 98.8±6.7 Egg ratio 2.12±0.09 2.14±0.17 2.11±0.13 2.19±0.15 Daily food price (yuan / kg) 2.46 2.43 2.39 2.35 Egg price (yuan / kg) 5.80 5.80 5.80 5.80 Egg production cost (yuan / kg) 5.22 5.20 5.04 5.15 Gross profit (RMB / kg) 0.58 0.60 0.76 0.65 45-48 weeks Egg production rate (%) 92.5±3.7 92.0±3.9 93.0±2.6 91.6±3.4 Average daily feed intake (grams / day) 101.2±6.2 100.4±5.1 100.9±6.8 100.3±5.1 Egg ratio 2.14±0.16 2.16±0.14 2.13±0.19 2.21±0.17 Daily food price (yuan / kg) 2.46 2.43 2.39 2.35 Egg price (yuan / kg) 5.80 5.80 5.80 5.80 Egg production cost (yuan / kg) 5.26 5.25 5.09 5.19 Gross profit (RMB / kg) 0.54 0.55 0.71 0.61

[0121] As shown in Table 6, when fermented bran was added to the feed at a mass fraction of 10% (Experimental Group II), the egg production rates of laying hens at weeks 41–44 and 45–48 were 92.6% and 93.0%, respectively, slightly higher than the control group (92.3% and 92.5%). There was no significant difference in average daily feed intake between the groups (P>0.05). When the amount of fermented bran added increased to 15%, the egg production rates at weeks 41–44 and 45–48 decreased to 91.4% and 91.6%, respectively, and the feed conversion ratio increased to 2.19 and 2.21, but there was no significant difference compared to other groups (P>0.05).

[0122] The unit price of the daily feed for laying hens using fermented bran at mass fractions of 5%, 10%, and 15% decreased from RMB 2.46 / kg to RMB 2.43, 2.39, and 2.35 / kg, respectively. The cost of laying hens in weeks 41-44 decreased from RMB 5.22 / kg in the control group to RMB 5.20, 5.04, and 5.15 / kg, while the gross profit per kilogram of eggs increased from RMB 0.58 / kg in the control group to RMB 0.60, 0.76, and 0.65 / kg. Similarly, the cost of laying hens in weeks 45-48 decreased from RMB 5.26 / kg in the control group to RMB 5.25, 5.09, and 5.19 / kg, while the gross profit per kilogram of eggs increased from RMB 0.54 / kg in the control group to RMB 0.55, 0.71, and 0.61 / kg.

[0123] Table 7

[0124] Egg-shaped index 1.32±0.02 1.31±0.03 1.32±0.01 1.31±0.02 Protein height (mm) 7.32±0.97 7.40±0.79 7.63±1.05 7.21±0.88 Egg yolk color <![CDATA[5.23±0.33 b ]]> <![CDATA[6.22±0.20 a ]]> <![CDATA[6.35±0.20 a ]]> <![CDATA[6.37±0.15 a ]]> Haas unit <![CDATA[71.29±2.11 b ]]> <![CDATA[77.56±3.04 a ]]> <![CDATA[79.52±2.94 a ]]> <![CDATA[71.06±2.64 b ]]> Eggshell thickness (mm) 0.32±0.02 0.32±0.02 0.32±0.03 0.32±0.02 Eggshell strength (N) <![CDATA[37.2±0.7 b ]]> <![CDATA[39.8±0.5 a ]]> <![CDATA[39.3±0.3 a ]]> <![CDATA[37.4±0.4 b ]]> Watermark Egg Rating <![CDATA[2.9±0.2 a ]]> <![CDATA[1.9±0.3 b ]]> <![CDATA[1.8±0.3 b ]]> <![CDATA[2.0±0.2 b ]]>

[0125] As shown in Table 7, the yolk color of eggs in the experimental groups at the end of week 8 (6.22, 6.35, 6.37) was significantly higher than that in the control group (5.23) (P<0.05). The Haugh units of eggs in experimental groups I and II were 77.56 and 79.52, respectively, both significantly higher than those in the control group (71.29) and experimental group III (71.06) (P<0.05). The shell strength of eggs in experimental groups I and II were 39.8 and 39.3, respectively, significantly higher than those in the control group (37.2) and experimental group III (37.4) (P<0.05). The watermark score of eggs in experimental groups I, II, and III were 1.9, 1.8, and 2.0, respectively, all significantly lower than the 2.9 of the control group (P<0.05). There were no significant differences in egg shape index, albumen height, and shell thickness among the groups (P>0.05).

[0126] In summary, the edible mushroom substrate obtained by the processing method provided in this application can significantly increase the crude protein content, acid-soluble protein content, and protein dispersion index of the substrate, while significantly reducing the content of crude fiber, neutral detergent fiber, and acid detergent fiber in the mushroom substrate of *Agaricus esculentus*. The processed edible mushroom substrate, when added at a feed weight fraction of less than 15%, can achieve the resource utilization of agricultural waste without negatively impacting the growth performance of fattening pigs, the production performance of laying hens, or the quality of eggs. This provides a reliable technical solution for reducing feed costs and increasing breeding efficiency, and is of great significance for the fine processing and development of non-grain feed resources.

[0127] The present application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present application. The descriptions of the embodiments above are only for the purpose of helping to understand the present application and its core ideas. It should be noted that those skilled in the art can make several improvements and modifications to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A method for processing spent mushroom substrate, characterized by, Includes the following steps: S1. Crush the edible mushroom substrate to a particle size of less than 2 mm to obtain substrate granules, wherein the edible mushroom substrate is deer antler mushroom substrate; S2. The mushroom husk granules are extruded and expanded using a twin-screw extruder to obtain the expanded material; The setup conditions for the twin-screw extruder are as follows: feeding zone 60~100℃, compression zone 90~130℃, extrusion zone 120~160℃, screw speed 100~300rpm, die diameter 5~7mm, and extrusion chamber pressure maintained at 0.5~2.0MPa. S3. Dry and pulverize the puffed material, and pass it through a 40-mesh sieve to obtain puffed mushroom bran powder; S4. Mix the puffed bacterial bran powder and soybean residue evenly to form a mixture, add cellulase to the mixture to form a fermentation substrate, and then add the mixed bacterial solution to the fermentation substrate to form a fermentation mixture; the mixed bacterial solution is formed by mixing Candida utilis solution, Lactobacillus plantarum solution and Bacillus subtilis solution; The mass ratio of the puffed bacterial bran powder to soybean residue is 9:1, and the amount of cellulase added is 10 IU / kg of the mixture; The mixed bacteria liquid is formed by mixing 5x10 5 CFU / mL Candida utilis bacteria liquid, 2x10 7 CFU / mL Lactobacillus plantarum bacteria liquid and 5x10 5 CFU / mL Bacillus subtilis bacteria liquid at a volume ratio of 2:80:18, and the inoculation amount of the mixed bacteria liquid is 10% of the mass of the fermentation substrate. S5. After the fermentation mixture is evenly mixed, it is put into a breathable fermentation bag, compacted, degassed and sealed, and placed at a constant temperature of 37℃ for 5 days for fermentation. The aeration rate is set to 0.3 vvm. During the fermentation process, the pile is turned over once every 12 hours to finally obtain the fermented edible fungus bran product.

2. The method of claim 1 wherein, The twin-screw extruder is configured with the following conditions: feeding zone 80°C, compression zone 110°C, extrusion zone 140°C, and screw speed 200 rpm.

3. The processing method according to claim 1, characterized in that, In S3, the moisture content of the puffed material after drying is below 15%.

4. The application of the processing method according to any one of claims 1 to 3 in the preparation of monogastric animal feed.

Images