When you buy mushrooms in the store, proper storage is essential to protecting them from rapid deterioration. Mushrooms are highly sensitive to moisture and will wilt or develop mold quickly if you do not store them under the proper conditions. Take care of your mushrooms right away after purchasing them to get the longest possible storage time.
Remove the mushrooms from the plastic-wrap packaging.
Check all of the mushrooms to be sure that the top of each mushroom is dry to the touch with no signs of slime or moisture. Throw away any mushrooms that withered due to drying out or are slimy and damp. Dispose of moldy or discolored mushrooms as well.
Put the remaining mushrooms into a paper bag to protect them from added moisture. Tightly close the paper bag by folding the top down.
Place the bag in a low-humidity drawer in your refrigerator for up to five days, checking regularly for signs of mold, moisture or discoloration.