It is very important that dried mushrooms are stored properly to insure long term and maximum freshness. Storing them in a cupboard which is warm will diminish shelf life. If you must store them in a cabinet make sure that the cabinet is both dark and cool. Place the mushrooms into either a plastic or glass container with a tight fitting lid. Our first recommendation, though, is freezing or storing in a refrigerator or freezer. Place the dried mushrooms in a clean, tight sealing freezer bag. The reason for maximum cold storage is because heat and moisture are the greatest enemies. The mushrooms should keep well for six months to a year.