How can the contamination rate of edible mushroom spawn be effectively reduced?

?Bottled fermented material one centimeter high

About 4 cm above the culture medium and below the bottle mouth, fill in 1-2 cm of fermented material, then sterilize. Because the fermented material itself is sterile, after inoculating the spawn, the mycelium quickly covers the entire upper part of the bottle, and the mycelium simultaneously feeds on the material. The advantage of this method is that foreign bacteria and molds are less likely to infect the culture medium, and the spawn age is uniform. The contamination rate can be reduced to below 3%.

?Wheat grain germination method

Let the wheat grains germinate before bottling and sterilizing. The storage substances of wheat grains are mainly starch, fat and protein. When the seeds imbibe water and their cellular physiological activity is reactivated, the activity of various enzymes increases, and these substances are decomposed during germination into simpler substances such as maltose, sucrose and amino acids, which are easily utilized by the mycelium, so the mycelium grows quickly. The specific method is: let the wheat grains used for spawn germinate all at once, with the sprouts growing to 1-2 times the length of the wheat grains, then thoroughly sun-dry and store them. On the day before making the spawn, soak the wheat grains for 12 h, then directly bottle and sterilize. The advantage of this method is that it saves the process of boiling the wheat grains, saves manpower and money, and the spawn runs fast with fewer foreign bacteria and molds, with a contamination rate of only 2%-3%.

?Using liquid spawn

Liquid spawn overcomes the shortcomings of solid spawn, and liquid spawn can be used directly as cultivation spawn for cultivation. The use of liquid spawn not only has a low probability of infection by foreign bacteria and molds, with the contamination rate reducible to about 2%, but also, from a long-term perspective, because its production does not use plastic bags, it causes no pollution to the environment and reduces the production cost of spawn. Inoculating at the lower part of the stock spawn bottle

?Starting inoculation from the bottom of the stock spawn bottle

We know that the spawn in the lower part of the stock spawn bottle has a short spawn age, vigorous vitality and fewer foreign bacteria and molds. After inoculation, the mycelium feeds on the material quickly and the contamination rate is low, so the contamination rate can be reduced to about 3%. In order to further reduce the contamination rate of the cultivation spawn, it is recommended to discard the upper 1/5 of the stock spawn at the mouth of a normal stock spawn bottle, to prevent contamination of the cultivation spawn by foreign bacteria and molds invisible to the naked eye.

Advancing or delaying the inoculation time in high-temperature seasons

Inoculate during the periods of lower temperature in July-August, such as in the morning or evening. Of course, if inoculation is carried out in a room with air conditioning, the effect is even better, and the contamination rate can be reduced to below 5%.