Why can't the pH of mushroom culture media be ignored?

The basis for mushroom growth is a suitable culture medium, and among the various parameters of the culture medium, pH is a very important one. For most mushrooms, the mycelium can grow at a pH between 4 and 8, but each variety has an optimal pH range, and this optimal range is much narrower. The optimal pH for most mushrooms is between 5.8 and 6.5.

For most industrialized mushroom companies, the pH of the culture medium can be well controlled, but some companies and most mushroom farmers cannot properly control the pH, and there are certain misunderstandings in this regard.

The pH after sterilization is what we need. What directly affects mycelium growth is the pH after sterilization. Many people only pay attention to the pH when mixing the substrate. During mixing, bagging and sterilization, the pH will change. How much the pH changes depends on the culture medium formula, ambient temperature, mixing and bagging time, and sterilization effect and time. Therefore, the pH during mixing should be adjusted according to the pH change after sterilization. That is to say, the pH must be measured both before and after sterilization.

Do not rely only on lime to adjust the pH. In mushroom culture medium formulas, lime (calcium hydroxide) is usually used to adjust the pH, but if only lime is added, the pH change caused by mixing, bagging and sterilization is very large, and the pH after sterilization becomes very low. Many people solve this problem by increasing the amount of lime added. Guxing Tianxia suggests that gypsum or calcium carbonate, substances that can buffer the pH, must be added to the formula, and at the same time the waiting time before bagging and sterilization should be shortened as much as possible.

Methods for measuring pH:

1. pH test paper

pH test paper is divided into wide-range pH test paper and precision pH test paper. Wide-range pH test paper can be accurate to 1, and precision pH test paper can be accurate to 0.1.

2. pH meter

A pH meter is an instrument specially used to measure pH, and its measurement accuracy can reach 0.01.

For mushroom farmers or small mushroom factories, pH test paper is sufficient, while industrialized mushroom production must use a pH meter.