How to Store Mushrooms. These elegant vegetables are actually the fruit of underground fungi. Try not to store them for long, or you'll lose the delicate flavor.
If the mushrooms are prepackaged, leave them in the packaging.
If the mushrooms are loose, place them in a paper bag and loosely fold the top of the bag over, or place them in a glass container and cover it with a dish towel or moist paper towel. Be sure to allow air circulation.
Store the mushrooms in the refrigerator, but not in the crisper.
Use the mushrooms within a few days, or within a week if they are packaged and unopened.