article : About Grifola frondosa

Grifola frondosa, referring to a mythical griffin, commonly known as Sheep’s Head, Ram’s Head and Hen of the Woods or Maitake, is an edible polypore mushroom. It grows in clusters at the foot of trees, especially oak. The Japanese call it "maitake" (pronounced [maitake]), literally meaning "dancing mushroom", and can be commonly found in almost all supermarkets across the nation. Hen of the woods should not be confused with the similarly named edible bracket fungi, chicken of the woods (Laetiporus sulphureus), also known as "sulphur shelf".

The fungus is native to the northeastern part of Japan and North America, and is prized in traditional Chinese and Japanese herbology as an adaptogen, an aid to balance out altered body systems to a normal level. Most people find its taste and texture enormously appealing, though the mushroom has been alleged to cause allergic reactions in rare cases.

Description

Like the sulphur shelf mushroom, hen of the woods is a perennial fungus that often grows in the same place for a number of years in succession. It occurs most prolifically in the northeastern regions of the United States, but has been found as far west as Idaho.

Hen of the woods grows from an underground tuber-like structure, about the size of a potato. The fruiting body, occurring as large as 60 cm, is a cluster consisting of multiple grayish-brown caps which are often curled or spoon-shaped, with wavy margins and 2-7 cm broad. The undersurface of each cap bears approximately one to three pores per millimeter, with the tubes rarely deeper than 3 mm. The milky-white stipe (stalk) has a branchy structure and becomes tough as the mushroom matures.

Maitake, an edible mushroom of the (Polyporaceae) family, can grow up to over 50 pounds (20 kilograms), earning this giant mushroom the title "King of Mushrooms.". In Japan, maitake make up the 4 or so major mushrooms used in the country (other being shiitake shimeji and enoki. There are used in a wide variety of dishes, often being a key ingredient in nabe or cooked in foil with butter.

Use in traditional Oriental medicine

The underground tubers from which hen of the woods arises has been used in traditional Chinese and Japanese medicine to enhance the immune system. Researchers have also indicated that whole maitake has the ability to regulate blood pressure, glucose, insulin, and both serum and liver lipids, such as cholesterol, triglycerides, and phospholipids, and may also be useful for weight loss.

Maitake is rich in minerals (such as potassium, calcium, and magnesium), various vitamins (B2, D2 and Niacin), fibers and amino acids. The active constituent in maitake for enhancing the immune activity has been identified in the late 1980s to be the protein-bound polysaccharide compound, beta-glucan, an ingredient found especially in the family of polyporaceae.

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