Sterilization and disinfection of edible fungi seed production technology

All kinds of microorganisms are composed of proteins. Heat sterilization can coagulate the proteins to kill the microorganisms. Heating sterilization is economical, effective, simple and easy to perform, and can be divided into two types: dry heat sterilization and moist heat sterilization. 1. Flame sterilization is a method that directly uses flame to kill microorganisms. It is suitable for sterilizing metal tools, glassware mouths and other items.

2. Dry heat sterilization is a method of sterilizing using hot air. Sterilization temperature 140℃-160℃, time 2-3h, it is only suitable for sterilization of metal and glassware. Electric drying oven is a commonly used equipment for dry heat sterilization. 1. High-pressure steam sterilization. Sterilization using high-temperature and high-pressure steam is the most effective and widely used sterilization method. Steam pressure is directly proportional to temperature. The steam pressure and time used for autoclaving should be determined based on the specific substance.

High-pressure sterilizers come in many forms and specifications, including vertical, horizontal, and portable types. They use electricity, steam, coal, etc. as energy sources.

When using high-pressure steam sterilizers, you should pay attention to the following points:

① The cold air in the sterilization pot must be exhausted; ② The matrix arrangement in the sterilization pot must be sparse. Make the steam flow smoothly; ③ Pressure increase and decrease should be slow during sterilization; ④ Pay attention to keeping the tampon dry during the sterilization process.

2. Normal pressure steam sterilization method: This is a method of steam sterilization using natural pressure. It can be sterilized using earthen steamer or steamed rice. Because the temperature at normal pressure is much lower than at higher pressure, the sterilization time is longer. Its advantages are simple structure, low cost, easy to make, and suitable for home seed production. 1, low-temperature sterilization method (pasteurization method) Some foods that are not resistant to high temperatures, such as milk, cider, soy sauce, etc., need low-temperature sterilization. Heating to 60°C for 30 minutes can kill pathogenic bacteria and most bacteria in the food. trophic body.

The post-fermentation of mushroom culture materials uses pasteurization to kill diseases, pests and bacteria that are harmful to mushrooms.

2. Boiling water disinfection method is mainly used to disinfect syringes and other equipment. The relevant equipment is boiled in boiling water for a certain period of time to kill the vegetative bodies of microorganisms.

3. Chemical disinfection method This is a method of sterilization using chemical agents. Types and concentrations of fungicides:

①Heavy metal salts: All heavy metal salts have harmful effects on microorganisms, such as silver nitrate, mercury chloride, etc.

② Oxidant: Commonly used oxidants include potassium permanganate, hydrogen peroxide, bleaching powder, bleaching essence, etc. The commonly used concentration of potassium permanganate solution is 0.1%, the concentration of chlorine tap water cleaner is 1ppm, and the concentration of bleaching essence is 400ppm. .

③. Organic compounds: Formaldehyde (formalin) 5% formaldehyde solution is used for surface disinfection of seeds. The original solution can be used for disinfection of inoculation boxes, culture rooms, cultivation rooms and other spaces. The fumigation dosage is 6-10ml/cm3.

Xinjiazuride: 0.25% Xinjiazuride solution can be used for skin and seed disinfection.

4. Drying and disinfection uses drying to cause microorganisms to lose water to achieve the purpose of sterilization or bacteriostasis, which is called drying and disinfection. Food, medicine, etc. can be stored for a long time after being properly dried, such as dried mushroom slices.

5. Osmotic pressure disinfection The method of using high osmotic pressure to sterilize or inhibit bacteria is called osmotic pressure disinfection. In a hypertonic solution, microbial cells die due to dehydration, plasmolysis, and inability to perform normal metabolism. Saltwater mushrooms are made using this principle.