Detailed Explanation of Key Points of Shiitake Mushroom Sterilization and Inoculation Techniques

Shiitake mushroom culture media mostly use the method of normal-pressure high-temperature sterilization to achieve the purpose of killing harmful organisms. (1) Bag substrate sterilization: Put the bags filled with substrate into the sterilization stove and sterilize at normal pressure. Before the substrate bags enter the stove, first add enough water to the steamer. When loading the bags into the stove, they must not be arranged in a "pin" shape; they should be stacked overlapping from top to bottom, with gaps left between rows so that airflow moves freely up and down. After the bags enter the chamber, immediately burn with a strong fire so that the temperature rises rapidly to 100°C within 6 hours and continues for 20-24 hours, without the fire dropping midway. Achieve "attack the beginning, protect the end, control the middle." After meeting the sterilization requirements, open the chamber door a crack and let the hot air slowly dissipate. Only when the temperature inside the chamber drops below 60°C may the bags be unloaded while hot. (2) Sterilization of the spawn-running room: The fumigation method is to place the tools used for taking bags out of the stove into the room 2-3 days before the inoculation room is used, seal the doors and windows so that no air leaks, sprinkle a small amount of water on the ground, then ignite 1-1.5 kg of sulfur. After the sulfur gas contacts water, it generates carbon dioxide. Fumigate for more than 20 hours, which can not only sterilize but also kill insects, kill mites, and drive away mice. After the substrate bags enter the inoculation room, when the bag temperature drops below 30°C, place all the tools and tables and stools used for inoculating spawn into the room, and use formaldehyde for a second fumigation disinfection. The dosage per room is 1-1.5 kg, placed in a small pot or basin and heated to evaporate, so that it all vaporizes. After 8-10 hours, the disinfection purpose can be achieved. The inoculation method generally uses stick spawn: during inoculation, generally 2 people form one group; 1 person holds the spawn bag and wipes it in a straight line with an alcohol cotton ball, while the other person holds the mouth end of the spawn bottle with the left hand, inserts the pointed end vertically into the bag, and leaves the flat end outside 3-5 mm. It must not be inserted crookedly, so as to avoid contamination by foreign bacteria. For each bag, inoculate 3 rows in a "pin" shape, with 3 holes equally spaced in each row. One bottle of spawn inoculates 10 bags. After inoculation, stack the inoculated spawn bags in a "well" shape to a height of 5-6 layers or arrange them neatly on the culture rack. Then splash 500 g of formaldehyde into the space of each room, close the doors and windows tightly, and enter the spawn-running period management.