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A Mushroom; is fungi that is large enough to be seen by the naked eye. Mushrooms grow above and below ground and should have a desirable taste, aroma and texture, without being poisonous. Though we think of them as vegetables, Mushrooms ("Champignons" in French and "Fungi" in Italian) are a fungus and not the typical plant-based veggie we are used to seeing. For example, Mushrooms don’t make their own food through photosynthesis like most familiar plants. Instead they feed off other growth materials and organisms to get their sustenance. Feeding off other growth materials defines a “heterotroph.” Plants which create their own food are labeled “autotroph.”

The bulk of the Mushroom is made up of wiry strands called "Mycelium," which tends to grow underground or out of sight. The Mycelium is there even when we don’t see any Mushrooms. Some of them can go quite a distance. In fact, the largest organism on earth is thought to be a Honey Mushroom discovered in the Pacific Northwest. It went on for miles under the earth.

The part that most of us consider a Mushroom is actually only the fleshy fruiting body of the organism. We should say that again, right? Basically, when it feels that the time is right to reproduce, the organism sends out spore towers (mushrooms) to fire off reproductive spores into the environment. Because of their reproductive role, Scientists call the whole Mushroom a “Sporophore,” which means “spore tower” in Greek.

With the scientific terms it may be a bit confusing. Put more simply the edible Mushrooms that we fancy are analogous to the apples of an apple tree. They are the fruit of the larger fungus.

The typical Mushroom (sporophore) typically consists of a Cap (Pileus) and a Stem or Stalk (Stipe). Because they come in various shapes and sizes not all Mushrooms fit the model.

Even though the word “Mushroom” is believed to have been derived from “Mousseron,” an ancient French word for moss, only a few centuries ago, fossil evidence suggests that Mushrooms have been on earth for ninety million years and some of the oldest active mushroom colonies grow in rings near Stonehenge in the U.K. 

In Ancient Egypt only the Pharaohs were sacred enough to even touch Mushrooms which were thought to convey immortality. By the time of Ancient Greece, Mushrooms were treated as famine food, similarly to how acorns were viewed. In Ancient Rome, Mushrooms (called Boleti in Latin) were much more valued. The stoic writer Seneca loved them enough to give them up as part of his asceticism. Diphilus of Siphnos took time to pen some Mushroom recipes in the third century BC and Apicius wrote up some more in the fourth century BC.

Other ancient cultures like the ancient Chinese, who may have been cultivating Shiitake Mushrooms on rotting logs since their earliest history, and the Aztecs thought of Mushrooms as “Food of the Gods.” Many ancients even believed that they could convey superhuman strength.

Today, there are approximately 14,000 to 38,000 species of mushrooms found throughout the world (depending on your source), and only 60-70 species are poisonous but still many cultures have historically been mycophobic, or afraid of mushrooms, believing that since some mushrooms lead to death, all fungi should be avoided. The United States, Britain, and Canada are traditionally Mycophobic, along with most of the Middle East and South America.

The French philosopher Voltaire (1694-1778) is credited with saying, “A dish of mushrooms changed the destiny of Europe.” Voltaire was referring to the death of King Charles VI, who ate death cap mushrooms (Amanita phalloides) and the subsequent turn of events: the War of Austrian Succession that turned into a global war, known by the American colonies as King George’s War, affecting the British, Spanish, Austrian, French and people as far away as India: all because of mushrooms.

Ironically, the French are considered mycophilic—lovers of Mushrooms—and so are the Russians, Chinese and Japanese. In fact, Mushrooms have been used since pre-history as an herbal medicine in Asia.

The ancient Chinese valued the Ganoderma Lucidum mushroom (also known as Líng Zhī, the “Spirit Plant”) which was supposed to support the bodies’ life force and which has the longest record of medicinal use (since 200 B.C.). The ancient Japanese called this same mushroom Mannentake or the “10,000 Year Mushroom.” Grifola Frondosa, another fungus was worth its weight in silver in Ancient Japan, though modern science has not discovered any therapeutic benefits for humans from Grifola Frondosa.

And though some Mushrooms are still used for medicinal purposes, the majority of modern Mushrooms produced are relished in our global pantry for their earthy flavor and general nutrition. And we are eating more every year. Americans consume, on average, 4 pounds of Mushrooms a year, up from one pound a year in 1965. The Chinese have us beat by a mile. They consume about 22 pounds of Mushrooms per year.


Because their environment is controlled to produce daily results, cultivated Mushrooms grow throughout the year. Industry almost thinks of modern cultivated Mushrooms as being “Seasonless” since Mushrooms are harvested every shift.

The acknowledged season for Wild Mushrooms is from late spring into the fall. We are couching our terms because many different varieties, like Morel Mushrooms, have their own seasonal timing and others like White Button Mushrooms, which grow in the dark, have their own methods of determining time (temperature, CO2, moisture).


With many types of Mushrooms grown in natural and controlled environments throughout the world today, fresh mushrooms can generally be found in American grocery stores year around. Dried Mushrooms, Canned Mushrooms, Frozen Mushrooms and Mushroom Powders are also a year round option.


As we mentioned, Mushrooms are a fungus and not technically plants. As a distinct organism, with unique characteristics, they require different growing conditions than a run-of-the-mill garden Vegetable.

First of all, Mushrooms don’t create their own food from soil and sunlight through photosynthesis like plants. Instead they feed off of decaying matter which makes them “heterotrophs.” Also, the bulk of the Mushroom fungus organism, the mycelium, tends to grow underground, or at least out of sight. It is there even when we don’t see any Mushrooms sprouting from the earth. Some of them can go quite a distance. In fact, the largest organism on earth is thought to be a Honey Mushroom discovered in the Pacific Northwest. It went on for miles under the earth.

The part that most of us consider a Mushroom is actually only the fleshy fruiting body of the organism. We should say that again, right? In nature, Mushrooms exist in a vegetative state, below ground, most of the time. They only go into a reproductive state, sending up Mushrooms (also called fruiting bodies) to spread spores, when they are triggered to do so by cues in their environment such as seasonal light, cold or precipitation. This is why we see so many Mushrooms sprout up after a rain.

Basically, when it feels that the time is right to reproduce, the organism sends out spore producers (mushrooms) to fire reproductive spores into the environment. Because of their reproductive role, Scientists call the sprouting, spore-firing, Mushroom a “Sporophore,” which translates as a “Spore Producer.”

With the scientific terms it may be a bit confusing. Put more simply the edible Mushrooms that we fancy are analogous to the apples of an apple tree. They are the fruit of the larger fungus. Instead of seeds, Mushrooms have spores.

Because they come in various shapes and sizes not all Mushrooms fit the model, but the typical Mushroom (sporophore) consists of a Cap (Pileus) and a Stem or Stalk (Stipe). Mushrooms tend to prefer moist environments (95-100% humidity) and can grow quickly on apparently open ground, especially after heavy rains. That being said, Mushrooms are found in deserts, on beaches, even in the occasional snow drift.

Mushrooms come from three primary sources: indoor trays, outdoor logs and wild harvesting / foraging.  Larger commercial Mushroom farmers usually use the first two styles noted and grow their Mushrooms on various substrates (wood chips, sawdust, mulched straw, certain manures, corncobs, nut shells, etc.) preferred by the species being cultivated. Generally, the ideal substrate has moisture levels of about 50%-75% and contains enough nitrogen and carbohydrates to promote rapid growth.

Insects, Bacteria and other fungi can constitute a parasitic risk to growing Mushrooms.

Mushrooms may be foraged as well, and even though we discourage it, there are plenty of guides to help people determine which specimen they’ve discovered on a mushroom picking expedition or on their front lawn after a heavy rain. If you decide to take this dangerous route, make sure to have an experienced person guide you. Double-check what you’ve picked before eating it.  For us, the grocery store is the perfect foraging ground, without any of the extra fun or risk.

Many vendors sell Mushroom Growing Kits for home users aiming to experiment. There is also a good book by Paul Stamet called “The Mushroom Cultivator: A Practical Guide to Growing Mushrooms at Home.” If you want to grow Mushrooms in a larger way, Paul Stamet’s other major work: “Growing Gourmet and Medicinal Mushrooms“ is very helpful. These last three links go offsite to Amazon.


Production of Edible Mushrooms is known as fungiculture. Worldwide production of consumable mushrooms is currently in the neighborhood of 7.7 million tons across more than 70 countries.  

According to the U.N.’s Food and Agriculture Organization, China is the world’s largest producer of Mushrooms suitable for human consumption, producing around 32% of all the mushrooms across the globe. The Netherlands produces about 10%, France about 6% and Poland about 4%.

In the U.S., which produces about 16% of worldwide production, most of our cultivated Mushrooms are grown in Pennsylvania, California and Florida. Rural Chester County, PA contains the town of Kennet Square, about 40 miles west of Philadelphia, which is known as the Mushroom Capital of the World. If their great Mushroom Festival each September did not cement their claim, the density of mushroom growers would. Over 70 mushroom farms are clustered nearby helping Pennsylvania account for 47% of our domestic American Mushroom production and more than $453 million in revenue. Many people don’t know it, but Mushrooms are the number one agricultural product in The Keystone State, even ahead of Corn. Both White Button Mushrooms (340 million pounds) and Premium Specialty Mushrooms are grown and distributed from Pennsylvania. 

One of the largest Specialty Mushroom purveyors is Phillips Gourmet (35 million pounds), part of the storied Phillips Mushroom Farm that invented cooling houses and year round production in the late 1920’s. They were also the first to cultivate Shitaki Mushrooms on sawdust logs. Today, they cultivate 9 premium Mushrooms and Cremini Mushrooms and Portobello Mushrooms too in their over 1,000,000 square feet of growing space. The links to Phillips go off site to their domains. By the way, we spoke to Jim Angelucci, the general manager of Phillips, about some of our obscure Mushroom questions and he was really helpful with us.

Phillips uses “Pennsylvania Double,” a windowless, chilly concrete building built into the side of a hill to produce its Mushrooms. Each building contains twenty four 60 x 5.5 foot Mushroom beds stacked six deep.

The largest single site Mushroom farm in Pennsylvania (and the U.S.) is located outside of Chester County. It is called Creekside Mushrooms Ltd. and it is located in an old limestone mine in Worthington, PA north of Pittsburgh. Creekside covers 2,030 acres above ground but 150 miles of tunnels 300 feet below ground which encompass 800 acres of Mushroom growing area. They produce about 23 million pounds but have a 60 million pound growing capacity and are vertically integrated on site. Their Organic Mushrooms are sold under the “Moonlight” brand.

Wild Mushroom foraging is a good sized agricultural business as well. The Pacific Northwest is best known for foraging but mushroom hunters go out all over the country.


As mentioned above there are about 14,000 Mushrooms species. Over 2000 of them are Edible Mushrooms varieties.

The bulk of the Mushrooms, about 93%, are in the scientific family Agaricales, which are also known as “gilled mushrooms.” Many of the fleshy and edible Mushrooms belong to the family Agaricales.

Some Edible Wild Mushrooms that we don’t see often belong to Agaricales too including specimens like: The Field Mushroom (Agaricus campestris), The Horse Mushroom (Agaricus arvensis), and The Prince Mushroom (Agaricus augustus).

Within the family Agaricales, the genus Amanita contains some edible Mushrooms (notably the American Caesar’s Mushroom) and some of the most dangerous Mushrooms found worldwide. The genus Amanita is responsible for approximately 95% of the fatal Mushroom Poisonings each year. The Destroying Angel Mushroom is in this genus, as is The Death Cap Mushroom (Amanita phalloides) which contains the toxin α-amanitin and accounts for almost 50% of Mushroom deaths all by itself.

When it comes to poisonous mushrooms, there are subgroups defined by the type of poisoning: Amanita, Muscarine, Hallucinogenic, and Coprinus. Each have different toxins involved and characteristics displayed when consumed. Because of the possibility of confusion, mycologists discourage foragers, other than well-versed experts, from procuring any specimens from this genus. If you think you have eaten a poisonous mushroom, rather than see what happens, it’s best to go to the nearest emergency clinic or call Poison Control.

Medicinal Mushrooms are commonly classified within the genus Ganoderma. These beneficial Mushrooms tend to be shiny and include the Lingzhi mushroom (Chinese) also known as the Reishi Mushroom (Japanese).

By the way, the terms “mushroom” and “toadstool” are purely unscientific labels applied to different varieties of fungus. While there’s no real scientific difference or definition, the two terms have come to mean different things in the common parlance. The name “toadstool” is often given to those fungi that are inedible or poisonous, while “mushroom” is generally BUT NOT ALWAYS reserved for those that are safe to eat.

The most commonly cultivated Edible Mushroom species are Button Mushroom (most common in the U.S.), Cremini Mushrooms, Portobello Mushrooms, Shiitake Mushrooms, Oyster Mushrooms, Morel MushroomHen of the Woods Mushroom (aka Wine Cap Mushroom and Maitake Mushrooms, Lions Mane Mushrooms, Reishi Mushrooms, Nameko Mushrooms(aka Butterscotch Mushrooms), Velvet Foot Mushrooms, Brown Beech Mushrooms, Pioppino Mushrooms(aka Chestnut Mushrooms), and Royal Trumpet Mushrooms (aka King Oyster Mushroom).


Mushrooms can be found in most local grocery store in various forms including: Fresh Mushrooms (whole & prepped), Dried Mushrooms, Canned Mushrooms and Frozen Mushrooms. Some types of Mushrooms are even sold as a Mushroom powder or Mushroom Extract.

The specific details of what to look for in each type of Mushroom varies but generally when looking for Fresh Mushrooms look for young Mushrooms in prime condition, with whole, closed, clean, caps and no signs of bruising or sliminess. Look under the Mushroom Cap for the “ring,” the soft covering that joins the edge of the cap to the stem. It should be intact and covering the Gills so that the gills are covered and cannot be seen. If you can see the gills, the Mushroom is past its prime.

Because they are very moist (about 90% water), Mushrooms should appear and feel “springy,” that is firm and dry, without actually being dry or shriveled. The longer the Mushroom has been sitting on your grocer’s shelf the darker it will be with more brown discoloration.

Aroma can also help you make better Mushroom purchasing decisions. Good, fresh Mushrooms will smell earthy. The stronger the earthiness, the more flavor the Mushroom contains. Sour or fishy smelling Mushrooms should be avoided. Mold growth and sliminess are other definite signs that the Mushrooms are bad.

We tend to avoid buying pre-sliced, fresh Mushrooms because it is harder to tell how many mushroom caps you are getting. This can be a problem if a particular recipes calls for mushrooms by the count (the certain number of whole mushrooms) not by volume or weight.

Also cutting into the product in a factory someplace starts the clock running on moisture loss and Oxidation. We can’t know how long the Mushrooms have been in transit.

Of course, Fresh Mushrooms are not the only way to go. Dried Mushrooms are frequently a smart option because they tend to cost less and actually have a better, more concentrated, flavor than fresh Mushrooms. The trade-off is that they are a little lacking in the texture department.

When shopping for Dried Mushrooms look for packages that are well sealed with no mold and no visible moisture inside the package.

Canned Mushrooms or Frozen Mushrooms are also available. They are usually packed in opaque packaging so there is not a lot of inspection possible. Make sure that the can is not banged up or dented and that any bag is well sealed. After that your purchasing decision should be influenced mostly by the reputation of the brand, your experience with the brand and the price.

You can also defy the seasons and order your own Mushroom Growing Kits, online. This link goes off site to Amazon.

The details of what to look out for when buying specif Mushrooms varies a lot from one Mushroom type to another. To learn more about purchasing specific Mushroom types, see that Mushroom's specific Resource Page

For example, see Button Mushrooms to learn more about what to look for when buying them. 


Fresh Mushrooms are a fairly perishable item. Excessive moisture degrades fresh Mushrooms and can make them soggy.

When brought home from the store, or farm stand, they should be stored in their original cardboard container on a shelf in the refrigerator. If you want to remove the plastic wrap, if any, and cover the Mushrooms with a dry paper towel that is fine. Placing them under wax paper or in a paper bag is good as well.

We don’t recommend using the higher humidity crisper drawer for moisture-sensitive Mushrooms. Stored as described above, Fresh Mushrooms should last about 5-7 days in the refrigerator. Stored at room temperature they will only last a day or so. Because of their moisture content, we don’t suggest freezing fresh Mushrooms at home. If you Sauté them first they can be frozen.

If you found a great deal and want to store an abundance of fresh Mushrooms, you can Slice them and dry them at home. Dried Mushrooms should be stored in an airtight container in a cool dark place such as a cabinet or pantry. Stored this way they can last up to a year, maybe two. They can last even longer if they are frozen. Don’t forget that Dried Mushrooms will need to be Rehydrated before use.

The details of how to store specific Mushrooms and for how long varies a lot from one Mushroom type to another. To learn more about storing specific Mushroom types, see that Mushroom's specific Resource Page

For example, see Button Mushrooms to learn more about what to look for when storing them. 

Culinary Uses

Most Mushrooms are completely edible* (both Cap & Stalk), and most should not be eaten Raw. Even those that are deemed safe to be eaten Raw, should only be consumed uncooked in limited quantities.

Generally, Mushrooms are porous, and can pick up surrounding tastes when cooked. Most do so without losing their own flavor.

On Smart Kitchen’s Home Plate Mushrooms are Tender, Thin, Moist and Lean (C, T1, T3, M, L). We classify Mushrooms as “cooked” because not all Mushrooms can be eaten Raw and even those that can be should only be consumed Raw in limited quantities. We also classify them as Thin but many times the actual thickness will depend on the type of Mushrooms and how they are prepped.

Without question, Mushrooms are very moist (about 90% moisture). They are also low in Fat so classified as “Lean.”

Mushrooms can be attention-grabbing examples of Flair, the fourth of Smart Kitchen’s 4 Levers of Cooking. Smart Kitchen has some interesting Exercises that show how to sculpt Mushrooms. Two of them are: Turning Mushrooms and Carving Mushrooms.

Once prepped, some Mushrooms (check by variety), can be eaten Raw in Salads, Sandwiches, Crudités or Canapés. Raw their flavor is mild, but cooking brings out their fragrance and a “meatier” Umami taste. Mushrooms can also be cooked as a Raw Ingredient in dishes such as: Omelets, Scrambled Eggs, Sauces, Soups, Stews, Pilafs, Paellas, Risottos, Pizzas, Stuffing, etc. Cooking Mushrooms allows them to absorb flavors from other items in the pan and to deepen their natural Umami flavor. How you add Mushrooms into your favorites dishes is really only limited by your imagination.

Mushrooms can also be cooked independently as a Side Dish or Garnish. Since they are mostly water, they will shrink noticeably (approximately 50%) when heated to cooking temperatures. If using a Dry Heat Cooking Method with Fat Added, they will also absorb a lot of the cooking Fat so choose a good, flavorful Butter or Oil. Cooked Mushrooms can also be added to other dishes such as Pastas, Hamburgers, Sandwiches, Sauces, and many of the uses listed above for raw Mushrooms.

In the kitchens of America, Mushrooms are most commonly found as an ingredient in Tomato Sauce or as Pizza Toppings, but you will find them in Quiches, Frittatas, Vol au Vents, Tartlets, CrepesDuxelle, Mushroom Essence, etc., but we are just getting started.

Mushrooms are integral ingredients in dishes like CivetCoulibiac, and Mushroom FondueFumet is a concentrated Stock that is often made from Mushrooms. If a dish is described by the word "Champignon" it means that it is made with Mushrooms. Also, if a dish is described as "à la Forestiêre" it means that it is "of the forest" and should contain Mushrooms (usually Wild Mushrooms), Potatoes, and Bacon (or Salt Pork)..

Smart Kitchen’s Recipe section has a number of Mushroom recipes that work well with Mushrooms such as: Crab Stuffed Cremini Mushrooms, The Hunger Games Mushroom Soup, Wild Rice and Mushroom Soup, Kosher Mushroom Lasagna, Mushroom Gravy, Mushroom Clam Bisque, Roasted Mixed Mushrooms and Kosher Warm Mushroom & Sweet Potato Salad.

The details of how to use Mushrooms varies a lot from one Mushroom type to another. To learn more about using specific Mushroom types, see that Mushroom's specific Resource Page

For example, see Button Mushrooms to learn more about what to look for when using them. 

Portion Size

Allow 1-2 oz of Mushrooms per person.


The specific Resource pages on specific Mushrooms has more detailed information on Mushroom nutrition but in general Mushrooms are low in calories and very low in sodium (that’s what Salt is for) while providing important nutrients like Selenium, Potassium, Riboflavin, Niacin (two B Vitamins not often found in vegetables) and Vitamin D (when exposed to sunlight, Mushrooms make Vitamin D in their “skin” just like we do).

Mushrooms, are thought to stimulate the immune system and according to new research may help prevent certain kinds of cancers. See the Nutrition Sections of the various types of Mushrooms listed in Varieties).

Gluten Free


Low Fat


Low Calorie