The shelf life of auricularia auricula depends on its state. As long as it is pure dry, it will not break in three or four years. However, if the fungus is damp when sealed, or the fungus is not tightly sealed, it will be moldy or even moth-eaten, so it can't be eaten. If it is packaged auricularia auricula, the shelf life of auricularia auricula is based on the date on the packaging bag, but don't buy too much at a time to avoid mildew and deterioration of auricularia auricula due to improper storage.
You can soak the fungus in water first. After normal soaking, there will be a smell of fungus in the water. However, if the fungus is moldy, it will not smell like this fungus, but will produce the smell of rotten eggs and other rancid smells, so you can smell whether the fungus has gone bad by just smelling it.
Judge carefully
Normal auricularia auricula will appear black or dark brown with brightness after soaking for a period of time, but if the soaking time is too long, it will easily lead to deterioration of dried auricularia auricula, dull color and ugly appearance.
If the fungus has a pungent smell, it is likely to be inferior fungus with chemical antiseptic ingredients added. It may be that dried auricularia auricula has a musty smell after being left for too long, or drugs to promote the growth of auricularia auricula have been added in the production process. Drugs usually have a taste, which is likely to pose a threat to human health and induce various diseases.