(1) Look: good-quality fungus is large and thin, with black and smooth buds and gray back; adulterated fungus is thick and the buds tend to stick together.

(2) Touch: Good-quality fungus is dry to the touch and light in weight; adulterated fungus feels moist to the touch and is heavier in weight.

(3) Taste: The fungus tastes good, with a refreshing fragrance and no strange taste. If there is a salty taste, it means that it has been soaked in salt water, which increases the weight and makes money; the sweet taste is because it has been mixed with sugar syrup; and the astringent taste is because it has been soaked in alum water, which is very harmful.