Anyone contemplating going on a mushroom hunt would do well to join a mushroom hunters group or go with a knowledgeable person, advises Betty Ivanovitch of Golden Gourmet.
Each mushroom has its own characteristics, which make it difficult for novices to distinguish an edible mushroom from a poisonous one.
Steve Farrar, plant manager at Golden Gourmet, offers some advice for judging mushrooms for freshness.
Oyster: Make sure the gills underneath look fresh and crisp. Don't worry if the mushroom caps have a few cracks. They may change color from white to yellow as they age, but these mushrooms keep well for up to 10 days when stored in their original container or in a paper bag in the refrigerator. Discard any mushrooms that have a slimy feel.
Enoki: Color should be white to off-white and texture should be firm. Enokis get spongier as they age. They are usually sold in shrink-wrap packages which extend their shelf life to 21 days. Once open, enokis should be consumed within a day or two. A slight fermented smell is acceptable when the package is opened, but if the mushrooms smell like strong wine they have started to decompose.
Shiitake: Stay fresh from 2 to 3 weeks. They turn yellowish as they age, and white gills are the best indicators of freshness. Discard any mushrooms with sunken or dark spots on the cap.