Cultivating Cordyceps militaris requires attention to detail; getting three key steps right is very important

1. The sterilization step

Sterilization can generally be divided into two types, atmospheric pressure and high pressure, to kill and eliminate all microorganisms.

Atmospheric pressure sterilization generally uses an ordinary steamer, and the temperature will not exceed 100°C. It is low in cost, economical and practical, but the sterilization time is long. Timing starts after the water in the pot boils, and it needs to be steamed for at least 8-10 hours. It consumes a lot of fuel, and you must always watch the water level in the pot and add water at any time to prevent the pot from burning dry. High pressure sterilization means using a high-temperature steam sterilization pot, which is high in cost but does not take long to sterilize. After it automatically releases steam, maintain 1.5-2 kg/cm, corresponding to a temperature of about 126°C, for 1 hour. Whether using atmospheric pressure or high pressure, you must get the time right. The holding time must not be too short, and the density of bottles in the pot must also be arranged reasonably to achieve smooth steam flow, so as to achieve a thorough sterilization effect.

2. The inoculation step

As a Cordyceps producer, you must first know what the concept of aseptic operation is: completing the relevant procedures under conditions that exclude interference from all microorganisms other than the target fungus, so as to ensure a culture process in which the target fungus is obtained, that is, aseptic operation. The specific key points are as follows:

First, the entire operation is carried out in aseptic equipment such as an inoculation box or inoculation room, and the inoculation space must be thoroughly disinfected;

Second, the space where the culture is exposed must be a sterile area;

Third, before various tools come into contact with the culture, they must be sterilized by burning with an alcohol flame, and only after cooling may they contact the culture;

Fourth, the operator must do all disinfection work well before carrying out the operation;

Fifth, the time of each operation should not be too long, so as to avoid an increase in the base number of contaminating bacteria caused by gas exchange in the inoculation area.

3. The temperature and humidity step

Temperature and humidity are generally divided into two stages, namely the mycelium production stage and the fruiting body growth stage. During the mycelium growth stage of Cordyceps militaris, the suitable temperature is 5-30°C, with 18-25°C being most suitable, and the required relative air humidity is 65-70%. During the fruiting body growth and development stage, the suitable temperature is 15-26°C, with 20-22°C being most suitable. It is best not to exceed 28°C, and the required relative air humidity is 85-95%. Methods to increase humidity include watering the floor, spraying water, misting in the air, and so on. Be sure not to remove the bottle film and spray water or mist directly onto the fruiting bodies.