A method for preparing edible mushroom culture medium by using solid waste

Abstract

The application discloses a kind of methods for preparing edible mushroom culture medium using solid waste, belongs to edible mushroom culture medium production technical field, steps are as follows: culture medium raw material pretreatment, including animal manure and abandoned mushroom stick are mixed according to proportion and water is wetted fermentation, preliminary compost is carried out;Agricultural and forestry waste is cut, corn cob is crushed, and is respectively pre-wetted with water;Culture medium fermentation compost, including using corn cob, abandoned mushroom stick, animal manure, agricultural and forestry waste, humus, coal gangue, fermentation agent is used to prepare original fermentation material, and additives are added urea, salt mud, phosphorus gypsum, magnesium sulfate, potassium dihydrogen phosphate;Culture medium sterilization, including atmospheric steam sterilization and high-pressure steam sterilization.The application reduces the preparation cost of edible mushroom medium, and provides a new idea for the recycling of phosphorus gypsum, coal gangue, salt mud and other solid waste.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of edible fungus culture medium preparation, and particularly relates to a method for preparing edible fungus culture medium from solid waste. BACKGROUND

[0002] Phosphogypsum is a solid waste discharged in the production of phosphorus chemical products. It is stored and disposed in large quantities due to its low utilization rate, which not only causes environmental pollution, but also wastes resources. At present, the national phosphogypsum stockpile is as high as 800 million tons, and is increasing at a rate of 78 million tons per year. Phosphogypsum is rich in useful resources such as sulfur, calcium, phosphorus and silicon, and is idle as solid waste, which also causes waste of resources.

[0003] Coal gangue is a solid waste formed in the process of coal mining, and its annual output accounts for about 15-20% of the amount of coal mining and 25% of the amount of industrial waste emissions in China. According to surveys, the utilization rate of coal gangue in China is only 60-70%, and the utilization of coal gangue through combustion usually causes secondary pollution. Therefore, developing a green and environmentally friendly utilization approach for coal gangue is an urgent problem to be solved in the field of environment in China.

[0004] Salt mud is a slurry discharged in the process of preparing caustic soda by electrolyzing saturated sodium chloride solution in the alkali industry. At present, the main process method used by chlor-alkali plants in China is ion membrane method, and the main raw salt used is sea salt, supplemented by well salt, rock salt and lake salt. According to statistics, about 50-60 kg of salt mud is generated per ton of caustic soda produced, and with the continuous development of the chlor-alkali industry, the environmental problems caused by the large-scale storage of salt mud cannot be ignored.

[0005] Currently, in the application in the field of agriculture, phosphogypsum, salt mud is mostly used to prepare the modifier of acid, alkaline soil, or used as fertilizer utilization; coal gangue is mostly used to prepare organic compound fertilizer and microbial fertilizer. For example, a kind of functional organic fertilizer for improving saline-alkali soil and its preparation method (CN110015936A) proposes a kind of using double-belly mushroom residue, vegetable waste, phosphogypsum, pig manure, fly ash, phosphorus-solubilizing bacteria to prepare the biological fertilizer for improving low-salinity and low-alkalinity soil; a kind of coal gangue mineral fertilizer and its preparation method (CN113416109B) uses Bacillus GZU-Bac01 to convert the insoluble phosphorus, potassium, calcium, nitrogen and other nutrient components in coal gangue into nutrient components that can be absorbed by plants, so that the coal gangue is resource utilization; Wang Jianping et al. use the salt mud discarded by the chlor-alkali plant with sea salt as raw material, and mix the salt mud with peat and tung seed cake to modify the compost, and prepare an alkaline organic fertilizer for improving acid soil. The above methods are all limited to preparing biological fertilizer or soil modifier, and there is still a blank in the technical field of edible fungus culture medium preparation. Edible fungus is delicious, rich in various proteins and vitamins, and also has health care effects such as anti-cancer, and is widely loved by people. At present, lime, gypsum and other calcium sources are mostly used as culture medium in edible fungus cultivation, which has high cost, and a method for preparing edible fungus culture medium using low-cost calcium source is to be developed; it is very necessary to find a method for preparing edible fungus culture medium using phosphogypsum, coal gangue, salt mud and other industrial solid wastes.

[0006] Therefore, a method for preparing edible fungus culture medium using solid waste is proposed in the present application. SUMMARY

[0007] The present application aims to fill the blank of the technical field of edible fungus culture medium preparation using part of industrial solid waste, and proposes a method for preparing edible fungus culture medium using phosphogypsum and other solid wastes as low-cost calcium source.

[0008] In order to achieve the above technical effects, the present application is realized by the following technical scheme: a method for preparing edible fungus culture medium using solid waste, characterized in that it comprises the following steps:

[0009] S1, first, mix animal manure and discarded mushroom sticks in proportion and add water to wet and ferment, and obtain raw compost by pre-composting; then cut the agricultural and forestry waste and crush the corn cobs, and respectively soak them with water;

[0010] S2, mix the raw materials except corn cobs in S1 with humus soil, coal gangue, fermentation agent and fertilizer to obtain raw fermentation material; and turn over the raw fermentation material several times during the fermentation process; add nutrient material made of corn cobs, phosphogypsum and salt mud to the raw fermentation material and ferment during the first turning over to prepare initial edible fungus culture;

[0011] S3. Add magnesium sulfate, potassium dihydrogen phosphate and salt mud to the initial edible fungus culture to adjust the pH of the initial edible fungus culture and obtain the edible fungus culture.

[0012] S4. Add sawdust and wood chips into the edible fungus culture to adjust the carbon-nitrogen ratio, bulk density, and air gap inside the edible fungus culture; this will give you the initial edible fungus culture medium; then sterilize the initial edible fungus culture medium and cool it after sterilization to obtain the edible fungus culture medium.

[0013] Furthermore, in S1, the steps for preparing the initial compost are as follows:

[0014] S1.1 Mix animal manure with waste mushroom substrate at a ratio of 0.8-1:1.6-2;

[0015] S1.2 Add water during the mixing process so that the water content of the mixture is 46-53%;

[0016] S1.3. Ferment the mixture for 5 to 7 days; and during the fermentation process, turn the pile once when the pile temperature reaches 52 to 58℃ to obtain the original compost.

[0017] Furthermore, in S2, the steps for preparing the initial edible fungus culture are as follows:

[0018] S2.1. Animal manure (excluding corn cobs), waste mushroom substrate, and agricultural and forestry waste from S1 are mixed with humus and coal gangue at a ratio of 10:20:40:2:1 at 15-20℃ to obtain the original culture medium. At the same time, phosphogypsum is dried and pulverized to 180-200 mesh, and salt mud is dried and pulverized to 50-100 mesh to obtain nutrient raw materials.

[0019] S2.2. Mix fertilizer and fermentation agent at 15-20℃ in a ratio of 1000-2000:1 to obtain the original fermented nutrient; at the same time, weigh corn cob, phosphogypsum, and salt mud in a mass ratio of 30:1-2.5:2-4.5.

[0020] S2.3. Mix the original fermentation nutrient with the original culture medium at 15-20℃ to obtain the original fermentation material with a water content of 55-65%, a carbon-nitrogen ratio of 25-30:1, and a pH of 7.5-8.5, and carry out fermentation for 11-14 days.

[0021] S2.4. On the 5th to 6th day of fermentation, when the pile temperature is 55 to 65℃, the first turning of the pile should be carried out. Before the first turning, the weighed corn cobs, phosphogypsum, and salt mud should be mixed to obtain nutrient material with a pH of 7.5 to 8.5 and a moisture content of 55 to 65%. During the first turning, the original fermented material and the nutrient material should be mixed by layering them in a layered stacking manner.

[0022] S2.5. Turn the pile a second time 3-4 days after the first turning, and then turn it a third time 3-4 days after the second turning. After fermentation, the resulting initial edible fungus culture is dark brown, odorless, has a fermented aroma, contains white actinomycete colonies, has grass that is 11-16cm long, breaks easily when pulled, has uniform manure and grass, and is loose, non-sticky, and elastic.

[0023] Furthermore, in S1, the animal excrement is a mixture of the excrement of one or more animals; the waste mushroom sticks are a combination of one or more different waste mushroom sticks that have been recycled after one or two uses; the agricultural and forestry waste includes a combination of one or more fresh, clean, dry, insect-free, mold-free, and odorless crop straws or husks.

[0024] Furthermore, in S1, the cutting length of agricultural and forestry waste is 15-20cm; the crushed particle size of corn cob is 6-7.5mm; when soaking agricultural and forestry waste, water is applied for 2-3 days, 3-4 times a day; when soaking corn cob, water is applied for 4.5-5.0 hours.

[0025] Furthermore, in S3, the phosphogypsum contains 70-90% CaSO4·H2O by mass, 14.85-15.76% soluble phosphorus by mass, a pH value of 2.9-3.5, a Pb content of 14.8-15.6 mg / kg, a Zn content of 12.53-16.48 mg / kg, a Ni content of 0-0.28 mg / kg, a Cr content of 0.4-3.1 mg / kg, and an As content of 6.5-21.8 mg / kg; the coal gangue contains 21.6-30.9% organic carbon by mass and 291% Ba by mass. The salt mud contains approximately 416.05 mg / kg of minerals, with Zn content ranging from 87.96 to 103.82 mg / kg, Cr content from 80 to 123 mg / kg, Cu content from 23.09 to 37.91 mg / kg, Ni content from 12.75 to 33.01 mg / kg, and Pb content from 12.37 to 28.95 mg / kg. The salt mud is a non-mercury salt mud produced in the chlor-alkali industry using membrane electrolysis. The salt mud contains 44.77 to 52.31% CaCO3 by mass, 6.33 to 7.49% Mg(OH)2 by mass, and has a pH value of 10.9 to 12.3.

[0026] Furthermore, in S3, the mass concentrations of magnesium sulfate and potassium dihydrogen phosphate are 0.5–2.0 g / L; and the pH of the initial edible fungus culture is adjusted to 5.5–8.5.

[0027] Furthermore, in S4, the mass ratio of added sawdust to wood chips is 3.3–4.0:1; the carbon-nitrogen ratio inside the edible fungus culture is adjusted to 20–45:1, the bulk density is 0.42–0.51 g / cm3, and the air gap is 33–42%.

[0028] Furthermore, in S4, sterilizing the initial edible fungus culture medium refers to the initial sterilization by atmospheric pressure steam, which takes 60-100 minutes from ignition to the material temperature reaching 100°C, and the subsequent sterilization by high pressure steam, which takes 120 minutes after the material temperature reaches 100°C and is then raised to 121°C.

[0029] Furthermore, in S4, the post-sterilization cooling refers to natural cooling to 18-24°C within a sterile space.

[0030] The beneficial effects of this invention are:

[0031] 1) The method of this invention uses industrial solid waste such as phosphogypsum, coal gangue, and salt mud to prepare edible fungi culture medium. The main component of phosphogypsum is CaSO4·H2O, which meets the needs of edible fungi for calcium ions and sulfur. Phosphogypsum also contains soluble phosphorus, which provides the necessary phosphorus element for mushroom growth. The main components of salt mud are CaCO3 and Mg(OH)2. During the fermentation and composting process, the calcium and magnesium elements required by edible fungi can be converted from a precipitated state into an effective state that can be directly absorbed by mushrooms. At the same time, because it is alkaline, it can neutralize the acidity of phosphogypsum, thus adjusting the pH of the culture medium to a suitable range. Coal gangue contains various trace elements such as zinc, copper, iron, and rare earth elements, which can promote mushroom growth and increase mushroom yield. At the same time, coal gangue is rich in organic matter and can also replace part of the humus soil for edible fungi cultivation, thereby reducing the preparation cost of the culture medium.

[0032] 2) This invention uses phosphogypsum and salt mud to adjust the pH value of the culture medium. Slightly excessive calcium can reduce the accumulation of heavy metals by edible fungi, and can also reduce the toxicity of excessive magnesium, potassium, phosphorus, iron, zinc, copper and other elements in fertilizers to mushrooms.

[0033] 3) This invention uses industrial solid waste and agricultural solid waste to prepare edible fungi culture medium, providing a new method for the green, environmentally friendly and resource-based utilization of phosphogypsum, coal gangue and salt mud. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart illustrating the overall operation of the present invention;

[0036] Figure 2 This is a flowchart of the original composting process of the present invention;

[0037] Figure 3 This is a flowchart of the process for preparing the initial edible fungi culture according to the present invention; Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Example 1

[0040] This embodiment compares the heavy metal content in the culture medium prepared by this invention with national standards:

[0041] Theoretically, the addition of phosphogypsum, coal gangue, and salt mud would increase the heavy metal content in the culture medium prepared in this invention by the following amounts: Pb: 0.305–0.485 mg / kg, Zn: 1.037–1.246 mg / kg, Cr: 0.805–1.269 mg / kg, Ni: 0.13–0.33 mg / kg, As: 0.081–0.27 mg / kg, Ba: 2.91–4.16 mg / kg, and Cu: 0.23–0.38 mg / kg. National standards specify the heavy metal content of soils used for edible fungi cultivation and other substrates for edible fungi cultivation. Here, the more stringent standard (i.e., the one with the lower heavy metal limit) is selected for evaluation. Table 1 shows a comparison between the national standard for soil pollution risk screening values ​​for edible fungi cultivation soil and the heavy metal content in the culture medium prepared in this invention.

[0042]

[0043] Table 1

[0044] As can be seen from Table 1, the heavy metal content in the culture medium of the present invention, which is increased by the addition of industrial solid waste, is lower than the national standard in terms of total arsenic, total lead, total zinc, total chromium, total nickel, and total copper, and meets the requirements for edible fungi cultivation.

[0045] Example 2

[0046] This embodiment describes the preparation of a culture medium and the cultivation of *Morchella tessmannii*, based on the following ingredients: 40 parts corn stalks, 30 parts corn cobs, 10 parts chicken manure, 20 parts waste oyster mushroom substrate, 1.25 parts phosphogypsum, 2.25 parts salt mud, 2 parts humus, 1 part coal gangue, 0.1 parts magnesium sulfate, 0.1 parts potassium dihydrogen phosphate, and 0.1 parts fermentation agent (commercially available Jinbaobei brand fermentation agent). The specific steps include:

[0047] Preparation of culture medium:

[0048] (1) Mix chicken manure and waste oyster mushroom sticks with water until the moisture content is 50%, pre-ferment for 5 days, turn the pile once when the temperature is 55℃ to obtain the original compost; cut corn stalks into 15-20cm long sections in advance, pile them up, and water them for 2 days. Water them 4 times for each method of preparing edible fungi culture medium using solid waste, and turn the pile once in between; before adding fertilizer, corn cobs should be crushed into granules with a particle diameter between 6mm and 7.5mm and soaked in water for 4.5h.

[0049] (2) Mix the raw materials other than corn cobs in step (1) with humus, coal gangue and Jinbaobei edible fungus cultivation substrate fermentation agent to obtain the original culture medium. The mass ratio of fertilizer to fermentation agent is 1000:1. The initial fermentation temperature is 18℃. Use some phosphogypsum and salt mud to adjust the pH to 8.0 to obtain the original fermentation nutrient. Mix the original culture medium and the original fermentation nutrient to obtain the original fermentation material with a water content of 60%, and ferment it to obtain the original fermentation material.

[0050] (3) On the 6th day of fertilizer fermentation in step (2), the pile is turned over for the first time, and the pile temperature is 60℃. When turning the pile, the pre-wetted corn cobs, phosphogypsum ground to 200 mesh, and salt mud ground to 80 mesh are mixed to form a nutrient material with a pH of 8.0 and a moisture content of 60%. This mixture is added to the original fermentation material and fermented for 13 days to obtain the initial edible fungus culture. When adding the nutrient material to the original fermentation material, a layered stacking method of one layer of original fermentation material and one layer of nutrient material is used to mix the original fermentation material and the nutrient material to prevent the growth of green mold during the corn cob fermentation process. The initial edible fungus culture is obtained. Three days after the first turning, the pile is turned over for the second time. Four days after the second turning, the pile is turned over for the third time. The fermentation is completed to obtain a dark brown, odorless, fermented aroma, white actinomycete colonies, grass length of 11-16cm, which breaks easily when pulled, uniform manure and grass, loose culture material, non-sticky and elastic initial edible fungus culture.

[0051] (4) After the initial fermentation of the edible fungi culture is completed, add magnesium sulfate solution and potassium dihydrogen phosphate solution with a mass concentration of 0.5 g / L; add an appropriate amount of salt mud and adjust the pH of the fertilizer to 8.3. Add camphor wood chips and solid wood sawdust at a mass ratio of 3.5:1 to adjust the carbon-nitrogen ratio to 43:1, the bulk density to 0.48 g / cm3, and the air gap to 36%.

[0052] (5) After mixing evenly, pack the mixture into polypropylene plastic bags within 4 hours, tie the bag opening tightly with string or rubber band, and then put it into the sterilizer. The steam sterilizer should be heated at high heat to accelerate the temperature rise, and the material temperature should reach 100℃ within 80 minutes. After that, heat the mixture to 121℃ and sterilize it with high-pressure steam for 120 minutes.

[0053] (6) Cool the culture medium obtained in step (5) to 20°C in a sterile space to obtain the morel mushroom cultivation substrate; then take samples of the prepared substrate for testing.

[0054] (7) The morel spawn was placed into the prepared qualified culture medium for cultivation, and then the cultivated mushrooms were sampled and tested.

[0055] Example 3

[0056] This embodiment describes the preparation of a culture medium and the cultivation of *Morchella tessmannii*, using a culture medium made from 40 parts by weight of soybean straw, 30 parts by weight of corn cob, 10 parts by weight of sheep manure, 20 parts by weight of waste oyster mushroom substrate, 2.5 parts by weight of phosphogypsum, 4 parts by weight of salt mud, 2 parts by weight of humus, 1 part by weight of coal gangue, 0.1 parts by weight of magnesium sulfate, 0.1 parts by weight of potassium dihydrogen phosphate, and 0.1 parts by weight of fermentation agent (using commercially available Jinbaobei brand fermentation agent). The specific steps include:

[0057] Preparation of culture medium:

[0058] (1) Mix sheep manure and waste oyster mushroom substrate with water until the moisture content is 50%, and pre-ferment for 5 days. Turn the pile once when the temperature reaches 55℃. Cut soybean straw into 15-20cm long sections in advance, pile them up, and water them for 3 days. Water them 3 times for each method of preparing edible fungi culture medium using solid waste, and turn the pile once in between. Before adding fertilizer, corn cobs should be crushed into granules with a particle diameter between 6mm and 7.5mm and soaked in water for 5.0h.

[0059] (2) Mix the raw materials other than corn cobs in step (1) with humus, coal gangue and Jinbaobei edible fungus cultivation substrate fermentation agent to obtain the original culture medium. The mass ratio of fertilizer to fermentation agent is 1000:1. The initial fermentation temperature is 18℃. Use some phosphogypsum and salt mud to adjust the pH to 8.0 to obtain the original fermentation nutrient. Mix the original culture medium and the original fermentation nutrient to obtain the original fermentation material with a water content of 60%, and ferment it to obtain the original fermentation material.

[0060] (3) On the 6th day of fertilizer fermentation in step (2), the pile is turned over for the first time, and the pile temperature is 60℃. When turning the pile, the pre-wetted corn cobs, phosphogypsum ground to 200 mesh, and salt mud ground to 80 mesh are mixed to form a nutrient material with a pH of 7.5 and a moisture content of 60%. The mixture is added to the original fermentation material and fermented for 13 days to obtain the initial edible fungus culture. When adding the nutrient material to the original fermentation material, the original fermentation material and the nutrient material are mixed by layering the original fermentation material and the nutrient material in a layered stacking manner to prevent the growth of green mold during the fermentation of corn cobs. The initial edible fungus culture is obtained. Four days after the first turning, the pile is turned over for the second time. Four days after the second turning, the pile is turned over for the third time. After the fermentation is completed, the initial edible fungus culture is dark brown, odorless, has a fermentation aroma, has white actinomycete colonies, grass is 11-16cm long, breaks easily when pulled, the manure and grass are uniform, the culture material is loose, not sticky and elastic.

[0061] (4) After the initial fermentation of the edible fungi culture is completed, add magnesium sulfate solution and potassium dihydrogen phosphate solution with a mass concentration of 0.5 g / L; add an appropriate amount of salt mud and adjust the pH of the fertilizer to 8.0. Add camphor wood chips and solid wood sawdust at a mass ratio of 3.5:1 to adjust the carbon-nitrogen ratio to 42:1, the bulk density to 0.48 g / cm3, and the air gap to 36%.

[0062] (5) After the raw materials are mixed evenly, pack them into polypropylene plastic bags within 4 hours, tie the bag openings tightly with string or rubber bands, and then put them into the sterilizer. The steam boiler should be heated at high heat to accelerate the temperature rise, and the material temperature should reach 100℃ within 80 minutes. After that, heat the boiler to 121℃ and sterilize with high-pressure steam for 120 minutes.

[0063] (6) Cool the culture medium obtained in step (5) to 20°C in a sterile space to obtain the morel mushroom cultivation substrate; then take samples of the prepared substrate for testing.

[0064] (7) The morel spawn was placed into the prepared qualified culture medium for cultivation, and then the cultivated mushrooms were sampled and tested.

[0065] Example 4

[0066] This embodiment describes the preparation of a culture medium and the cultivation of *Morchella tessmannii*, using a culture medium made from the following ingredients: 40 parts cottonseed hulls, 30 parts corn cobs, 10 parts chicken manure, 20 parts waste oyster mushroom substrate, 1 part phosphogypsum, 0.5 parts gypsum, 2 parts salt mud, 2 parts humus, 1 part coal gangue, 0.1 parts magnesium sulfate, 0.1 parts potassium dihydrogen phosphate, and 0.1 parts fermentation agent (using commercially available Jinbaobei brand fermentation agent). The specific steps include:

[0067] Preparation of culture medium:

[0068] (1) Mix chicken manure and waste oyster mushroom sticks with water until the moisture content is 50%, and pre-ferment for 5 days. Turn the pile once when the pile temperature is 55℃. Pile cottonseed hulls in advance, water them for 2 days, water them 4 times a day, and turn the pile once in between. Before adding fertilizer, corn cobs should be crushed into granules with a particle diameter between 6mm and 7.5mm and soaked in water for 4.5 hours.

[0069] (2) Mix the raw materials other than corn cobs in step (1) with humus, coal gangue and Jinbaobei edible fungus cultivation substrate fermentation agent to obtain the original culture medium. The mass ratio of fertilizer to fermentation agent is 1000:1. The initial fermentation temperature is 18℃. Use some phosphogypsum and salt mud to adjust the pH to 7.5 to obtain the original fermentation nutrient. Mix the original culture medium and the original fermentation nutrient to obtain the original fermentation material raw material with a water content of 60%, and ferment it to obtain the original fermentation material.

[0070] (3) On the 6th day of fertilizer fermentation in step (2), the pile is turned over for the first time, and the pile temperature is 60℃. When turning the pile, the pre-wetted corn cobs, phosphogypsum ground to 200 mesh, and salt mud ground to 80 mesh are mixed together to form a nutrient material with a pH of 7.5 and a moisture content of 60%, which is added to the original fermentation material and fermented for 13 days. When adding the nutrient material to the original fermentation material, the original fermentation material and the nutrient material are mixed by layering the original fermentation material and the nutrient material in a layered stacking manner to prevent the growth of green mold during the fermentation of corn cobs and to obtain the initial edible fungus culture. The pile is turned over for the second time 3 days after the first turning, and then turned over for the third time 4 days after the second turning. The fermentation is completed to obtain a dark brown, odorless, fermented aroma, white actinomycete colonies, grass length of 11-16cm, which breaks easily when pulled, uniform manure and grass, loose culture material, non-sticky and elastic initial edible fungus culture.

[0071] (4) After the initial fermentation of the edible fungi culture is completed, add magnesium sulfate solution and potassium dihydrogen phosphate solution with a mass concentration of 0.5 g / L; add an appropriate amount of salt mud and adjust the pH of the fertilizer to 7.5. Add camphor wood chips and solid wood sawdust at a mass ratio of 3.5:1 to adjust the carbon-nitrogen ratio to 43:1, the bulk density to 0.48 g / cm3, and the air gap to 36%.

[0072] (5) After the raw materials are mixed evenly, pack them into polypropylene plastic bags within 4 hours, tie the bag openings tightly with string or rubber bands, and then put them into the sterilizer. The steam boiler should be heated at high heat to accelerate the temperature rise, and the material temperature should reach 100℃ within 80 minutes. After that, heat the boiler to 121℃ and sterilize with high-pressure steam for 120 minutes.

[0073] (6) Cool the culture medium obtained in step (5) to 20°C in a sterile space to obtain the morel mushroom cultivation substrate; then take samples of the prepared substrate for testing.

[0074] (7) The morel spawn was placed into the prepared qualified culture medium for cultivation, and then the cultivated mushrooms were sampled and tested.

[0075] Example 5

[0076] This embodiment describes the preparation of a culture medium and the cultivation of *Morchella tessella*, using a mixture of 60 parts by weight of cottonseed hulls, 30 parts of corn cobs, 10 parts of pig manure, 1.5 parts of gypsum, 1 part of quicklime, 3 parts of humus, 0.1 parts of magnesium sulfate, 0.1 parts of potassium dihydrogen phosphate, and 0.1 parts of a commercially available Jinbaobei brand starter culture. The embodiment also compares this preparation with Examples 2-4, and includes the following steps:

[0077] Preparation of culture medium:

[0078] (1) Mix the pig manure with water until the moisture content is 50%, and pre-ferment for 5 days. Turn the pile once when the temperature is 55℃. Pile cottonseed hulls in advance, water them for 2 days, water them 3 times a day, and turn the pile once in between. Before adding fertilizer, corn cobs should be crushed into granules with a particle diameter between 6mm and 7.5mm and soaked in water for 4.5 hours.

[0079] (2) Mix the raw materials other than corn cobs in step (1) with humus and Jinbaobei edible fungus cultivation substrate fermentation agent to obtain the original culture medium. The mass ratio of fertilizer to fermentation agent is 1000:1. The initial fermentation temperature is 18℃. Use some gypsum and quicklime to adjust the pH to 7.5. The original fermentation nutrient is obtained by mixing the original culture medium and the original fermentation nutrient to obtain the original fermentation material raw material with a water content of 60%, and then fermenting it to obtain the original fermentation material.

[0080] (3) On the 6th day of fertilizer fermentation in step (2), the pile is turned over for the first time, and the pile temperature is 60℃. When turning the pile, the pre-wetted corn cobs, gypsum ground to 180 mesh, and quicklime ground to 50 mesh are mixed together to form a nutrient material with a pH of 7.5 and a moisture content of 60%, which is added to the original fermentation material and fermented for 13 days. When adding the nutrient material to the original fermentation material, the original fermentation material and the nutrient material are mixed by layering the original fermentation material and the nutrient material in a layered stacking manner to prevent the growth of green mold during the fermentation of corn cobs and to obtain the initial edible fungus culture. The pile is turned over for the second time 3 days after the first turning, and then turned over for the third time 4 days after the second turning. The fermentation is completed to obtain a dark brown, odorless, fermented aroma, white actinomycete colonies, grass length of 11-16cm, which breaks easily when pulled, uniform manure and grass, loose culture material, non-sticky and elastic initial edible fungus culture.

[0081] (4) After the initial fermentation of the edible fungi culture is completed, add magnesium sulfate solution and potassium dihydrogen phosphate solution with a mass concentration of 0.5 g / L; add an appropriate amount of quicklime to adjust the pH of the fertilizer to 7.5; add camphor wood chips and solid wood sawdust in a mass ratio of 3.5:1 to adjust the carbon-nitrogen ratio to 43:1, the bulk density to 0.48 g / cm3, and the air gap to 36%.

[0082] (5) After the raw materials are mixed evenly, pack them into polypropylene plastic bags within 4 hours, tie the bag openings tightly with string or rubber bands, and then put them into the sterilizer. The steam boiler should be heated at high heat to accelerate the temperature rise, and the material temperature should reach 100℃ within 80 minutes. After that, heat the boiler to 121℃ and sterilize with high-pressure steam for 120 minutes.

[0083] (6) Cool the culture medium obtained in step (5) to 20°C in a sterile space to obtain the morel mushroom cultivation substrate; then take samples of the prepared substrate for testing.

[0084] (7) The morel spawn was placed into the prepared qualified culture medium for cultivation, and then the cultivated mushrooms were sampled and tested.

[0085] Example 6

[0086] The culture medium prepared by this invention has different specific implementation schemes depending on the different edible fungi. Here, we take the cultivation of morel mushrooms as an example. The fermentation agent used is the commercially available Jinbaobei brand fermentation agent. As described in Examples 2 to 4, the growth of morel mushrooms was monitored under the conditions of using different culture medium raw materials and the same culture medium raw materials but with different component contents. The cultivation results are shown in Table 2.

[0087] Experiment No. Mycelial growth rate (mm / h) Contamination rate (%) Days to initial fruiting (d) <![CDATA[Kernel weight (g / m 3 )]]> Example 1 0.4 5.8 91 288.4 Example 2 0.6 6.5 86 356.2 Example 3 0.3 5.6 95 149.6 Comparative Example 0.3 4.3 92 136.4

[0088] Table 2

[0089] As can be seen from Table 2, adding phosphogypsum and salt mud to the culture medium at 2.5% and 4.0% respectively has the effect of promoting mycelial growth and has good economic benefits.

[0090] Example 7

[0091] This embodiment describes a food safety test on *Morchella tessmannii* cultured using the methods described in this invention. The test is conducted using *Morchella tessmannii* cultured on the culture substrates prepared in Examples 2-5 as examples. Details are as follows:

[0092] Edible fungi absorb a large amount of nutrients during cultivation, but they also accumulate heavy metals. Related studies have shown that the mycelium and fruiting bodies of edible fungi have a certain capacity for accumulating common heavy metals. In terms of accumulation, the order is generally Cd > Hg > As > Pb. Generally, under the same production environment and cultivation conditions, straw-rotting fungi have a strong capacity for accumulating Cu, Ag, and Cd, while wood-rotting fungi have a higher capacity for accumulating Cr, Mg, Se, and Pb. Variations in internal and external factors such as different edible fungi varieties, different cultivation methods, and different ecological environments will all have different effects on the ability of edible fungi to accumulate heavy metals. Considering that morel mushrooms have a certain accumulation effect on arsenic, mercury, lead, cadmium, and chromium, with *Morchella tessmannii* showing the strongest accumulation effect on arsenic, this invention uses the cultivation of *Morchella tessmannii* as an example to illustrate that edible fungi cultivated on the culture medium of this invention meet edible standards. All tested morel mushrooms were normal in shape, plump and elastic, uniform in size, free of visible foreign matter (including contaminating bacteria), and showed no sour, foul, moldy, or burnt odors, insect infestation, or rot. The detection methods for lead, cadmium, chromium, arsenic, mercury, nickel, and copper were performed according to national standards, and the data are shown in Table 3.

[0093]

[0094] Table 3

[0095] As can be seen from Table 3, the heavy metal content in the morel mushrooms cultured on the culture medium of this invention is lower than the national standard, and meets the edible standards for edible fungi.

Claims

1. A method for preparing edible fungi culture medium using solid waste, characterized in that: Includes the following steps: S1. First, mix animal manure and waste mushroom sticks in a certain proportion and add water to moisten and ferment them to obtain raw compost; then cut agricultural and forestry waste and crush corn cobs, and soak them in water respectively. S2. Mix the raw materials in S1, except for corn cobs, with humus, coal gangue, fermentation agent, and fertilizer to obtain the original fermentation material; and turn the pile multiple times during the fermentation process; during the first turning, add the nutrient material made by mixing corn cobs, phosphogypsum, and salt mud into the original fermentation material and ferment it to obtain the initial edible fungus culture. S3. Add magnesium sulfate, potassium dihydrogen phosphate and salt mud to the initial edible fungus culture to adjust the pH of the initial edible fungus culture and obtain the edible fungus culture. S4. Add sawdust and wood chips into the edible fungus culture to adjust the carbon-nitrogen ratio, bulk density, and air gap inside the edible fungus culture; the initial edible fungus culture medium can then be obtained; then sterilize the initial edible fungus culture medium and cool it after sterilization to obtain the edible fungus culture medium. In S1, the steps for preparing the initial compost are as follows: S1.1 Mix animal manure with waste mushroom substrate at a ratio of 0.8-1:1.6-2; S1.2 Add water during the mixing process so that the water content of the mixture is 46-53%; S1.

3. Ferment the mixture for 5 to 7 days; and during the fermentation process, turn the pile once when the temperature reaches 52 to 58°C to obtain the original compost. In S2, the steps for preparing the initial edible fungi culture are as follows: S2.

1. Animal manure (excluding corn cobs), waste mushroom substrate, and agricultural and forestry waste from S1 are mixed with humus and coal gangue at a ratio of 10:20:40:2:1 at 15-20℃ to obtain the original culture medium. At the same time, phosphogypsum is dried and pulverized to 180-200 mesh, and salt mud is dried and pulverized to 50-100 mesh to obtain nutrient raw materials. S2.

2. Mix fertilizer and fermentation agent at 15-20℃ in a ratio of 1000-2000:1 to obtain the original fermented nutrient; at the same time, weigh corn cob, phosphogypsum, and salt mud in a mass ratio of 30:1-2.5:2-4.

5. S2.

3. Mix the original fermentation nutrient with the original culture medium at 15-20℃ to obtain the original fermentation material with a water content of 55-65%, a carbon-nitrogen ratio of 25-30:1, and a pH of 7.5-8.5, and carry out fermentation for 11-14 days. S2.

4. On the 5th to 6th day of fermentation, when the pile temperature is 55 to 65℃, the first turning of the pile should be carried out. Before the first turning, the weighed corn cobs, phosphogypsum, and salt mud should be mixed to obtain nutrient material with a pH of 7.5 to 8.5 and a moisture content of 55 to 65%. During the first turning, the original fermented material and the nutrient material should be mixed by layering them in a layered stacking manner. S2.

5. Turn the pile a second time 3-4 days after the first turning, and then turn it a third time 3-4 days after the second turning. After fermentation, the resulting initial edible fungus culture is dark brown, odorless, has a fermented aroma, contains white actinomycete colonies, has grass that is 11-16cm long, breaks easily when pulled, has uniform manure and grass, and is loose, non-sticky, and elastic.

2. The method for preparing edible fungi culture medium using solid waste according to claim 1, characterized in that: In S1, the animal excrement is a mixture of the excrement of one or more animals; the waste mushroom sticks are a combination of one or more different waste mushroom sticks that have been recycled after one or two uses; the agricultural and forestry waste includes a combination of one or more fresh, clean, dry, insect-free, mold-free, and odorless crop straws or husks.

3. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S1, the cutting length of agricultural and forestry waste is 15-20cm; the crushed particle size of corn cob is 6-7.5mm; when soaking agricultural and forestry waste, water is sprayed for 2-3 days, 3-4 times a day; when soaking corn cob, water is soaked for 4.5-5.0 hours.

4. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S3, the phosphogypsum contains 70-90% CaSO4·H2O by mass, 14.85-15.76% soluble phosphorus by mass, a pH value of 2.9-3.5, and heavy metal Pb content of 14.8-15.6 mg / kg, Zn content of 12.53-16.48 mg / kg, Ni content of 0-0.28 mg / kg, Cr content of 0.4-3.1 mg / kg, and As content of 6.5-21.8 mg / kg; the coal gangue contains 21.6-30.9% organic carbon by mass and 291-4% heavy metal Ba content. The salt mud contains 16.05 mg / kg of mercury, with Zn content ranging from 87.96 to 103.82 mg / kg, Cr content ranging from 80 to 123 mg / kg, Cu content ranging from 23.09 to 37.91 mg / kg, Ni content ranging from 12.75 to 33.01 mg / kg, and Pb content ranging from 12.37 to 28.95 mg / kg. The salt mud is a non-mercury salt mud produced by membrane electrolysis in the chlor-alkali industry, with CaCO3 mass percentage ranging from 44.77 to 52.31%, Mg(OH)2 mass percentage ranging from 6.33 to 7.49%, and pH value ranging from 10.9 to 12.

3.

5. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S3, the mass concentrations of magnesium sulfate and potassium dihydrogen phosphate are 0.5–2.0 g / L; the pH of the initial edible fungus culture is adjusted to 5.5–8.

5.

6. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S4, the mass ratio of added sawdust to wood chips is 3.3–4.0:1; the carbon-nitrogen ratio inside the edible fungus culture is adjusted to 20–45:1, the bulk density is 0.42–0.51 g / cm3, and the air gap is 33–42%.

7. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S4, sterilization of the initial edible fungus culture medium refers to the initial sterilization by atmospheric pressure steam, which takes 60-100 minutes from ignition to the material temperature reaching 100°C, and the subsequent sterilization by high pressure steam, which takes 120 minutes after the material temperature reaches 100°C and is then raised to 121°C.

8. The method for preparing edible fungi culture medium from solid waste according to claim 1, characterized in that: In S4, the post-sterilization cooling refers to natural cooling to 18-24°C in a sterile space.

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