“Edible” mushrooms are the fungi with no poisonous nor adverse affects when consumed by humans. They grow both above and below ground and may be wild harvested or cultivated.
Edible mushroom species have been found in association with 13,000 year old ruins in Chile, but the first reliable evidence of mushroom consumption dates to several hundred years BC in China. The Chinese value mushrooms for medicinal properties as well as for food. Ancient Romans and Greeks used mushrooms for culinary purposes.
No one has yet developed a simple test to tell if a mushroom is edible or not. Roman Emperors used “food tasters” to make sure that mushrooms were safe to eat.The old myths of cooking with a silver coin or spoon, and the Laotian belief that harmful mushrooms make rice turn red have not been substantiated.
Over 20 species of mushrooms are commercially cultivated. The most common are:
Enoki (enokitaki or golden needle mushrooms) – long, thin mushrooms grown in clusters on the stumps of the Chinese Hackberry tree and also on mulberry and persimmon trees. They exist in the wild and are also cultivated in a carbon dioxide-rich environment which ensures longer stems and a white color, as opposed to those found in the wild which are usually a darker brown. They are used in Asian cuisine, particularly in soups.
Oyster mushrooms – scalloped-shaped mushrooms that grow like “shelves” on the bark of dead hardwood trees. They have an anise-like aroma and can be gray, blue, pink, yellow or white. Occasionally tan caps can be found that grow up to 18 inches in diameter. Generally, oyster mushrooms can be harvested two or three times from the same bark during the growing season. Oyster mushrooms are used in stir-fry recipes since they have a thin cap which cooks quickly.
White mushrooms (“button”) – most commercially available mushroom. Freshest specimens have closed caps. Considered a universal mushroom, it has a mild, fresh flavor and may be cooked or eaten raw.
Portobellos (also baby bellas) – A cousin of the white mushroom, portobellos resemble an umbrella with thick, meaty flesh. The larger portobellos are often substituted for meat in sandwiches and vegetarian recipes.
Shitake – the second most widely cultivated mushroom in the world. The shiitake has a medium-sized, umbrella-shaped, tan to brown cap. The edges of the cap roll inwards. The underside and stem are white.
The Chinese were the first to cultivate this mildly fragrant mushroom more than six hundred years ago. Yield and quality varied from year to year until scientific techniques were developed. Japanese scientists developed a method of inserting pencil-shaped plugs of mycelial spawn grown from specially selected varieties into holes bored in oak logs. Today shitake mushrooms are grown in the United States as well as in Asian countries on a variety of materials containing cellulose, such as sawdust enriched with rice bran.
The following species are commonly harvested from the wild:
Porcini (Pig mushroom) – sold fresh in Europe but is only available dried in the U.S. Known in Germany as “stone mushrooms”, in Russia as “white mushrooms”, in Albanian as “wolf mushrooms”, and in France as the “cèpe”.
Chanterelle – The yellow chanterelle is one of the best and most easily recognizable mushrooms, and can be found in Asia, Europe, North America and Australia. The cap is fleshy, with wavy, rounded cap margins tapering downward to meet the stem. The gills are not the usual thin straight panels hanging from the lower surface of the cap, as we see in the common store mushroom. Instead, the ridges are rounded, blunt, shallow, and widely spaced. At the edge of the cap they are forked and interconnected. The chanterelle’s aroma is variously described as apricot- or peachlike. The European and Asian varieties are about the size of a thumb, while North American varieties can weigh up to two pounds.
Morels – usually found in open scrub, woodland or open ground in early spring as the snow melts. They resemble tall pointed hats pitted with hollow spaces. Because of it’s appearance, it is sometimes referred to as the “sponge mushroom.” Avoid morels whose caps are soft or mushy, or become granular when rubbed, as they old and wormy.
Maitake (also “hen of the woods” or “sheep’s head”) – a large, hearty mushroom commonly found on or near stumps and bases of oak trees.
Matsutake (“pine mushroom”) – highly prized in Japanese cuisine, this mushroom grows most abundantly along the coast of the state of Washington. The cap is dark brown, scaled, and bell-shaped, and perches atop a massive round stem that looks like the cut section of a ripe sugar-cane stalk.With age, the cap and stem develop rusty stains where bruised. It is distinguished by a clean, spicy odor.
Buying and cleaning mushrooms
When buying mushrooms, look for firm caps and wholesome odors. If the mushrooms are beginning to decay, brown, slimy, smelly soft spots will appear on their surface. Avoid fragmenting gills or pore surfaces, and worm holes.
Do not clean mushrooms until you are ready to use them as they will deteriorate rapidly when wet. Cut off the lower portion of the stems, and brush gently with a nylon mushroom brush or wipe off with a damp cloth to remove any soil or growing medium. Rinse the gills, if exposed, as they can harbor insects. Dried mushrooms will keep in the refrigerator or freezer for several months and can be rehydrated in hot water when you are ready to prepare them.
After cleaning the mushrooms, using as little water as possible, cut into slices about 3/8 inch thick. The slices should be of uniform width so that they will dry at the same speed. Plan to work on your mushrooms as soon as you bring them home. Do not leave them lying around to deteriorate. Avoid overlapping the slices on trays so that they will dry evenly.
If you do not have a commercial food dehydrator, you can dry your mushrooms in flats of wire screen doors, or plastic mesh above ovens, fireplaces, or heating units. One mushroom enthusiast used an abandoned refrigerator with a fan and a 75-watt light bulb.
When slices are completely dry, place them in metal cans or glass jars. If you are uncertain about their state of dryness, transfer them into paper bags, and hang in a dry, warm place over an oven or fireplace for a few days. Then put them into containers, adding a few dried bay leaves or a handful of whole black peppers to discourage insect pests. Be sure to label containers with the date and the species identification.
Mushrooms, when exposed to UV light, convert ergosterol, a chemical found in large concentrations in many mushrooms, to Vitamin D2.
In Japan and China the chemicals found in shiitakes have been analyzed for medicinal properties, although some of their medicinal claims have not been proven. Extracts have been used in treating cancer, and claims have been made that they reduce cholesterol, enhance sexual power, prolong life, kill viruses, and improve circulation.