1 How long is the shelf life of dried fungus? The shelf life of dried fungus is generally about 1-2 years. Usually some packaged fungus will also have a shelf life marked on it. However, as long as the black fungus is completely dry (the national standard stipulates that the moisture content is less than 14%), it will generally not go bad after three or four years, and will not attract insects or rats. However, if the fungus is moist when it is sealed, or if the fungus is not tightly sealed and the moisture returns, it will become moldy or even insect-eaten and cannot be eaten. 2. Preservation method of dried fungus 1. If you don’t eat the black fungus you bought home for a long time, do not store it in a food bag. In this way, the black fungus will easily absorb water and change its flavor. The first step is to put a layer of clean paper underneath. Just the kind that packs roast duck. 2. Then put the fungus in the carton, and then put the carton in the refrigerator. If there is no refrigerator, just put it in a cool and dry place. If the taste changes due to improper storage, if it is not serious, you can brew it with boiling water first, and then soak it in cold water. If it is serious, do not eat it. 3 Tips for purchasing dried fungus 1. Look: high-quality black fungus is dark black, the ear flap is slightly spread, the surface of the flower is black and shiny, the back of the ear is dark gray, and there are no lumps; the flower is slightly small or moderate in size, the ear flap is slightly rolled, Flowers with black but matte surfaces are medium-sized; small and broken in shape, with rolled, thick or stiff ear valves, and the lowest ones are gray or brown. Some unscrupulous traders use pigments to "process" black fungus and soak it in clean water. The water will soon turn black. The true color of Tremella fuciformis is ordinary white, slightly yellowish, and the yellow color is unevenly distributed. High-quality Tremella fuciformis has thick and whole flesh, a round canopy, a diameter of more than 3 cm, no peduncle and no impurities. Inferior white fungus has thin flesh, spots, pedunculated heads, impurities, and irregular flower shape. If it is too white and beautiful, it may be smoked with sulfur. 2. Pinch: No matter black or white, the water content of high-quality fungus is very low. It feels very light in the hand and is easily broken when pinched. 3. Smell: Fresh black fungus has no sour or smelly smell. If stored for a long time, there will be sour gas or other peculiar smell due to protein and fat denaturation. If there is a musty smell, it means it has become damp and has deteriorated. If the Tremella has a burnt smell, it may have been over-dried during processing. Although it is edible, the quality and flavor are poor. When buying white fungus, you can also open a small hole in the packaging bag and smell it for any pungent smell. If there is, it means there is more sulfur dioxide remaining. 4. Taste: pure fungus, no smell when licked lightly. Some unscrupulous traders will soak fungus in alum water, alkaline water or sugar water to increase the weight. When purchasing, you can lick the back of the fungus. If it has an astringent, alkaline, sweet, or irritating or spicy taste, it means that it has undergone additional "processing" and is of poor quality.