Soak the edible amount of fungus for the meal, soak it in cold water for 1 hour to 2 hours each time, not more than 4 hours at most.

It is not recommended to consume black fungus soaked overnight because the optimal growth temperature of Pseudomonas syringae is 37 degrees Celsius and the optimal temperature for poison production is 26 degrees Celsius. Long soaking, coupled with the high temperature of the open air environment, it is easy to brew a powerful toxicity of rice fermentation bacterial acid. Black fungus after soaking if you find a strange odor or hand feel mucus, to be discarded immediately.

Extended information:

Dried black fungus itself has no toxins. Normal black fungus in a short period of time during the foaming process to produce the probability of rice fermentation bacterial acid is very low; but if a long period of time soaking, coupled with the external environment is not clean, there is a possibility of being contaminated by Pseudomonas aeruginosa and generate rice fermentation bacterial acid, such as soaking the surrounding the simultaneous presence of expired and spoiled food, or soaking containers are not washed clean and residual food debris. These spoiled and leftover food residues will become the breeding ground for the formation of MEA. Moreover, the acid is heat-resistant and normal cooking methods cannot destroy its toxicity.

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