In the process of foaming, a large number of bacteria will multiply and make fungi deteriorate. If the soaking time is too long, it is recommended not to eat it to avoid toxic reaction. Normal fungus can generally be soaked in warm water for an hour.

Auricularia auricula mainly grows in China and Japan. Most of China is auricularia auricula and auricularia auricula in Qinling Mountains.

There are two kinds of auricularia auricula: wild and cultivated. Solid seeds are spike-shaped, leaf-shaped or cup-shaped, thin and wavy, with a width of 3- 10 cm and a thickness of about 2 mm, and are fixed on the substrate with lateral short stalks or narrow attachments. Dark brown in color, soft and gelatinous in texture, thin and elastic, translucent when wet, and shrinking into brittle and hard keratin similar to leather when dry.

Auricularia auricula:

Auricularia auricula [L. EXHook. ) Underw, also known as black vegetables, auricularia auricula and auricularia auricula, belongs to the family Auricularia, belonging to the genus Auricularia, and is a precious edible and medicinal gum fungus in China.

China is the hometown of Auricularia auricula. As early as more than 4000 years ago, the Chinese nation recognized and developed auricularia auricula, and began to cultivate and eat it. There are also records about eating black fungus at the royal banquet in the Book of Rites. At present, auricularia auricula is planted in northeast, north, south, southwest and coastal provinces of China.