Overview of primary fermentation of white button mushroom compost 

Overview of primary fermentation of white button mushroom compost 

white button mushroom compost  needs to be mixed with straw, livestock and poultry manure, gypsum, water, etc., and fermented with ventilation, oxygen control and temperature control. The whole process takes about 12 days, depending on the raw materials and equipment. The main equipment includes forage, chicken manure metering bucket, mixing line, and throwing machine. Ventilation facilities include high-pressure breathable floor, fan (wind pressure above 8000 Pa) and control system.

2. Purpose of primary fermentation
(1) All raw materials are mixed evenly according to the appropriate ratio. According to the physical and chemical properties and carbon-nitrogen ratio of the raw materials, they are calculated and then reasonably proportioned. Of course, the specific proportions are completely different for different raw materials with different moisture, ash content, and carbon-nitrogen ratios. Usually, the initial nitrogen content of Agaricus bisporus is 1.6%~1.8%, or the carbon-nitrogen ratio of the ingredients is 25:1~30:1.

(2) The physical structure of the raw materials is softened after microbial fermentation, and the substances are transformed and humified. In the primary fermentation, through the growth of microorganisms, the large-scale reproduction of microorganisms will decompose chicken manure, ammonia nitrogen, simple sugars, and hemicellulose into microbial proteins, and generate a large amount of heat to raise the temperature of the pile to 80℃. The high temperature causes the pile to produce a caramelization reaction to form humus, which is black and forms a humus-protein complex that is beneficial to the growth of mushrooms.

(3) The primary fermentation accumulates high-temperature microorganisms and initially eliminates a large number of harmful microorganisms. In the initial stage of the primary fermentation, the raw materials contain a large number of mesophilic microorganisms, which are competitive bacteria for the mycelium of Agaricus bisporus, that is, harmful bacteria. In the first stage of the primary fermentation, 25~45℃ is the large-scale growth of bacteria and mesophilic microorganisms. These microorganisms mainly use simple sugars, starch, ammonia nitrogen, and some hemicelluloses to grow rapidly. With the growth of microorganisms, a large amount of heat is generated. Through ventilation adjustment, the temperature is gradually raised to 45~60℃ to enter the second stage. At this time, a large number of high-temperature microorganisms and actinomycetes begin to grow in large numbers, while the mesophilic microorganisms in the first stage die in large numbers due to the unsuitable temperature. In the second stage, the growth rate of microorganisms is very fast and they can decompose complex organic matter such as cellulose in large quantities, soften the raw materials quickly, and require a large amount of ventilation in this stage. In about 6 hours, the temperature of the pile can exceed 60℃ and enter the third stage. In this stage, the growth of microorganisms begins to be inhibited, and it is necessary to reduce ventilation to gradually increase the temperature of the material. In this stage, the cold area of ​​the fermentation material (around the fermentation tank) still has some radiation to provide heat supply, and some extremely high-temperature microorganisms can still survive in the pile. After about 12 hours of fermentation, the pile temperature will reach about 709 and enter the fourth stage. In this stage, the microorganisms rarely need to reduce ventilation again to gradually increase the temperature to about 80℃ and basically stabilize.

3. Purpose of transfer
During a fermentation process, the temperature around the pile and the temperature inside and in the center cannot be completely consistent, so it is usually necessary to transfer the pile again 2~3 times for fermentation.
The purpose of this process is:
(1) Further mix the raw materials through transfer.
(2) Supplement water through transfer to make the fermentation more complete.
(3) Further ferment the unfermented areas inside and outside the pile

4. Primary fermentation material indicators
Moisture content 71%~74%, nitrogen content 1.8%~2.0%, organic nitrogen about 1.4%, ammonium nitrogen <0.6%, pile color black, no anaerobic acid odor but ammonia, pH 8~8.5, ash content 20%~30%, fluffy structure without knots