Real Food Encyclopedia | Mushrooms

Mushrooms, hundreds of species of which are consumed today, have probably been foraged since prehistoric times. Cynthia D. Bertelsen, in her book “Mushroom: A Global History,” notes that the Roman philosopher Galen wrote about wild fungi; shiitakes (Lentinula edodes) were likely cultivated in China and Japan as early as 600 CE. Today, the types that dominate U.S. grocery aisles are of the species Agaricus bisporus — white mushrooms, brown mushrooms, button mushrooms, cremini mushrooms and portobello mushrooms are simply A. bisporus at different stages of maturity.

Hallucinogenic mushrooms have also long had a place in human history. According to Bertelsen, archaeological evidence of mushrooms used “spiritually” dates back to as early as 10,000 BCE, and there is documentation of use in many cultures — including the Ancient Greeks, the Mayans and the Vikings.

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Did you know?

  • Some mushroom species — 74 of them, according to estimates — are bioluminescent, meaning they produce and emit light. The glow of mushroom bioluminescence tends to be green.
  • The first reference to mushrooms in a U.S. cookbook can be found in 1824’s “The Virginia House-Wife.”
  • The North American Mycological Association maintains a Registry of Mushrooms in Works of Art.

What to look for when buying mushrooms

Edible mushrooms vary tremendously in size, shape and color, and can be available both fresh and dried, depending on the variety. Look for fresh mushrooms without slimy, moldy or black spots. Some dirt is okay (just wash before eating). For varieties with gills — the feathery material on the underside of the cap — the more open the gills, the older the mushroom. This is not necessarily a bad thing, as older mushrooms can be more flavorful.

Sustainability of mushrooms

Serious mushroom cultivation can be a fairly energy-intensive operation, requiring high-tech climate and humidity control. Many mushroom farming operations are trying to become more environmentally friendly — including by disposing of “spent mushroom substrate,” the stuff that cultivated mushrooms grow on, by composting or spreading it on fields — but problems persist.

Even wild mushroom foraging has some negative environmental impacts. The rise in popularity of wild harvesting has taken its toll in some places. As more and more people get into foraging, some of the old-school rules are being broken: People are leaving trash, trampling plants and taking more than what is allowed by state regulations.


Mushrooms made the 2023 “Clean 15” from the Environmental Working Group, but don’t assume that mushrooms are grown organically; several types of pesticides can be used in conventional commercial cultivation. Check out your local farmer’s market to see if you can find locally grown, organic mushrooms. There are smaller mushroom-growing operations popping up across the country.


Wild mushrooms are generally foraged in the spring and fall, depending on variety and geography. Most cultivated mushrooms are available year-round.

Eating mushrooms


Fresh mushrooms don’t hold up incredibly well to storage, generally speaking. Most can be kept in the crisper drawer — ideally, in a paper bag — for three to four days, tops, before they begin to shrivel or get slimy. Dried mushrooms can be sealed and stored in a dry place for a year or more.


The great debate: Should you rinse your mushrooms or not? While the general advice is to wipe mushrooms with a damp paper towel to avoid water-logging, some chefs say it’s okay to give them a quick rinse if you do so right before cooking.

Mushrooms can be cooked any way your heart desires — fried, braised, roasted, grilled, steamed, sautéed or even raw. They pair well with dairy (especially cheese and sour cream), meats, eggs, other vegetables and fresh herbs. They are yummy tossed onto pizzas, sliced into salads, mixed into risottos and sautéed as a side dish. Eastern Europe is famous for its mushroom dishes, like this Russian mushroom-barley soup, and foraging is an important part of the cultural heritage. A variety of mushrooms play a big part in Chinese cuisine, too, where they pair well with broccoli or bok choy. Mushrooms also make an appearance in many traditional French dishes, like mushroom duxelles.

Dried mushrooms must be reconstituted before you use them, and will have a much more concentrated taste than fresh mushrooms. They are great braised or added to dishes like risotto; save their soaking liquid to add in some extra flavor.


To preserve mushrooms to cook with later, it’s fairly simple to freeze or oven-dry them. You can also try salting and fermenting mushrooms or making mushroom pickles.


While different mushroom varieties have slightly different nutritional compositions, most are quite high in riboflavin (Vitamin B2) and niacin (Vitamin B3), and also contain some minerals, like copper, selenium, phosphorus and potassium. They even have a bit of protein.

Mushrooms have been used medicinally by cultures all over the world. Shiitakes may be beneficial to the immune system and help lower cholesterol; button mushrooms contain antioxidants; psilocybin, the active compound in hallucinogenic mushrooms, may help alleviate depression.


Top photo by New Africa/Adobe Stock.