Pleurotus ostreatus, the oyster mushroom, is a common edible mushroom. It was first cultivated in Germany as a subsistence measure during World War I and is now grown commercially around the world for food. It is related to the similarly cultivated king oyster mushroom. Oyster mushrooms can also be used industrially for mycoremediation purposes. The oyster mushroom is one of the more commonly sought wild mushrooms, though it can also be cultivated on straw and other media. It has the bittersweet aroma of benzaldehyde which is also characteristic of bitter almonds.
Both the Latin and common names refer to the shape of the fruiting body. The Latin pleurotus (sideways) refers to the sideways growth of the stem with respect to the cap, while the Latin ostreatus (and the English common name, oyster) refers to the shape of the cap which resembles the bivalve of the same name. Many also believe that the name is fitting due to a flavor resemblance to oysters.
The name oyster mushroom is also applied to other Pleurotus species, so P. ostreatus is sometimes referred to as the Tree Oyster Mushroom or the Grey Oyster Mushroom to differentiate it from other species in the genus. Other names may exist:
Straw Mushroom
Hiratake (“Flat Mushroom” in Japanese)
The mushroom has a broad, fan or oyster-shaped cap spanning 5–25 cm; natural specimens range from white to gray or tan to dark-brown; the margin is inrolled when young, and is smooth and often somewhat lobed or wavy. The flesh is white, firm, and varies in thickness due to stipe arrangement. The gills of the mushroom are white to cream, and descend on the stalk if present. If so, the stipe is off-center with a lateral attachment to wood. The spore print of the mushroom is white to lilac-gray, and best viewed on dark background. The mushroom’s stipe is often absent. When present, it is short and thick.
The oyster mushroom is frequently used in Japanese, Korean and Chinese cookery as a delicacy. It is frequently served on its own, in soups, stuffed, or in stir-fry recipes with soy sauce. Oyster mushrooms are sometimes made into a sauce, used in Asian cooking, which is similar to oyster sauce. The mushroom’s taste has been described as mild with a slight odor similar to anise. The oyster mushroom is best when picked young; as the mushroom ages, the flesh becomes tough and the flavor becomes acrid and unpleasant.
Oyster mushrooms are widely cultivated and used in Kerala, India where a wide variety of dishes are prepared from them. Oyster mushrooms are mainly cultivated in large clear polyethylene bags with buns of hay layered in the bags, and spawn sown between the layers.
Oyster mushrooms are also used in the Czech and Slovak contemporary cuisine in soups and stews in a similar fashion to meat.
Oyster mushrooms contain small amounts of arabitol, a sugar alcohol, which may cause gastrointestinal upset in some people.
I will briefly present some of the most worldwide cultivated oyster mushroom species. An important aspect worth considering here is that some Pleuortus species are thermophilic (they love higher temperature ~30-32 °C / 86-89.6 F) while some other species are chriophilic (lower temperatures such as ~8-15 °C / 46.4-59 F are more suitable for their development). Taking into account this, we may choose what species to cultivate and in what season. Another important aspect is the sensitivity level of the mushroom; therefore we have more or less sensible species to the environmental factors present in the grow room. One thing is certain, these factors influence the mushroom developmental process, and are composed of biotic (e. g., competitive molds, flies, nematods, or other competitive mushrooms for the same substrate), while a-biotic factors refer to developmental conditions such as: temperature, humidity, ventilation, and light.
Species of Cultivated Pleurotus:
1. Pleurotus citrinopileatus (golden oyster mushroom)
2. P. djamor (flamingo, salmon or pink oyster mushroom)
3. P. eryngii (king oyster mushroom)
4. P. ostreatus (oyster mushroom)
5. P. florida (the Florida oyster)
6. P. pulmonarius (the lung oyster, Phoenix mushroom)
7. P. cornucopiae (branched oyster mushroom)
8. P. columbinus
9. P. cystidiosus
10. P. flabellatus