1. Auricularia can be divided into dried and fresh auricularia. Generally, dried auricularia auricula is non-toxic after soaking overnight, but it is easily contaminated by bacteria during soaking, while fresh auricularia auricula is toxic to some extent, which may be toxic after soaking overnight.

2. Most fresh auricularia auricula contains porphyrin, which is a photosensitive chemical substance. After being absorbed by people, this substance may cause solar dermatitis, rash and even dyspnea. During the processing of fresh auricularia auricula into dried auricularia auricula, most porphyrins will be destroyed and decomposed. After the dried auricularia auricula is formed, there is only a small amount or almost no porphyrin, and even if it is absorbed by the human body, it usually does not have much reaction, so the processed dried auricularia auricula itself is nontoxic. Long-term consumption of auricularia auricula is made by soaking dried auricularia auricula. Because dried auricularia auricula is non-toxic, it is generally not poisoned by soaking in water for one night.

3. Although dried auricularia auricula is non-toxic, it is easily influenced by environmental factors in the foaming process, resulting in the pollution of bacteria, molds and other microorganisms, producing toxins, and poisoning reactions such as diarrhea and vomiting may occur after eating.

4. Therefore, it is suggested that the process of soaking auricularia auricula should not be too long and the ambient temperature should not be too high. Don't eat fungi if they smell or rot. If it has abnormal reaction after eating, it should seek medical attention immediately to avoid serious consequences.