Proper cleaning and storage of mushrooms is a must.
When it comes to cleaning and storing mushrooms, follow these helpful hints:
The best way to clean fresh mushrooms is to wipe them with a clean, damp cloth. If you must rinse them, do it lightly, then dry them immediately -- and gently -- with paper towels. Never soak fresh mushrooms in water because it ruins their texture.
As for storage, prepackaged mushrooms should stay in the package, but loose mushrooms or those in an open package should be stored in a paper bag or in a damp cloth bag in the refrigerator. This allows them to breathe so they stay firm longer. Storing mushrooms in a plastic bag causes them to deteriorate quickly.