Oyster mushrooms (Pleurotus ostreatus) are a type of edible mushroom that are shaped like oysters. They’re one of the most popular mushrooms in the world.
Learn more about the benefits that oyster mushrooms may have for your health.
What Are Oyster Mushrooms?
Mushrooms are neither plant nor animal. They’re a type of fungus. There are over 10,000 known types of mushrooms.
Oyster mushrooms come in a range of different colors:
- Gray
- Golden
- Brown
- Tan
- Cream
Oyster mushrooms have gills that are white colored. They also have very short stems. Oyster mushrooms can grow up to about 9 inches high.
Oyster mushrooms can be found in the wild. They grow on dead or decaying logs in temperate and tropical forests. They were first cultivated by a German scientist in 1917 and are now the third most commonly cultivated mushroom in the world, most often grown in China.
Oyster Mushrooms Nutrition
Oyster mushrooms are low in calories and rich in minerals and vitamins. A 100-gram serving of oyster mushrooms contains:
Calories: 33
Protein: 3 grams
Fat: 0.4 grams
Carbohydrate: 6 grams
Dietary fiber: 2.3 grams
Potassium: 420 milligrams
Folate: 38 micrograms
Niacin (vitamin B3): 5 milligrams
Pantothenic acid (vitamin B5): 1.3 milligrams
Riboflavin (vitamin B2): 0.3 milligrams
Oyster Mushrooms Health Benefits
Mushrooms have been used in folk medicine for centuries in countries ranging from ancient Rome and Greece to China and India. The health benefits of mushrooms, though, have only been thoroughly studied scientifically in recent decades. These studies have been mostly test-tube and lab based, so more studies are needed to confirm the effects of mushrooms on people.
High in Antioxidants
Oyster mushrooms are rich in antioxidant compounds such as flavonoids and phenolics. Antioxidants are substances that reduce or prevent cell damage in your body. Antioxidants fight free radicals, which are linked to diseases like cancer.
Scientists have found that oyster mushrooms contain higher amounts of antioxidants than other types of cultivated mushrooms. This is probably why oyster mushrooms are used in so many dietary supplements.
Mushrooms are also rich in an amino acid called ergothioneine. Scientists say that this substance has potent antioxidant activity. Edible mushrooms are the main source of ergothioneine.
May Help Heart Health
Eating oyster mushrooms may be beneficial for your heart. This may be due to beta-glucans, which are fibers that make up the cell walls of yeast and fungi. When fermented by bacteria in your gut, beta-glucans produce short-chain fatty acids that are able to reduce your body’s production of cholesterol.
In a study of 20 adults, participants who drank a soup made with 30 grams of dried oyster mushrooms for 21 days had lower triglycerides, oxidized LDL (bad) cholesterol levels, and total cholesterol compared to those who ingested a placebo.
A study of 89 participants with diabetes found that eating oyster mushrooms for 7 days lowered not just their blood sugar but also their cholesterol, triglycerides, and blood pressure.
May Improve Cognitive Health
In a study of 663 participants aged 60 and above, those who ate more than two portions of mushrooms a week had a lower risk of developing mild cognitive impairment.
May Lower Cancer Risk
Scientists have found that mushrooms are high in bioactive compounds. A review of several scientific studies found that eating about 18 grams of mushrooms (about two medium mushrooms) a day may help lower your cancer risk by 45 percent. This may be due to mushrooms’ special compounds like ergothioneine.
May Help Control Blood Sugar Levels
Some limited studies have found that regularly eating oyster mushrooms may have an effect on your blood sugar level. One study on hospitalized patients with type 2 diabetes found that eating 150 grams of oyster mushrooms three times a day for 7 days reduced fasting blood sugar levels by about 22 percent. After 1 week without mushrooms, fasting blood sugar levels increased by about 13%.
Another study of healthy participants found that taking a mixture of powdered mushroom in water for 14 days reduced their fasting blood sugar levels by 6 percent.
Oyster Mushrooms Taste
Oyster mushrooms have a sweet, delicate taste. Some types have an anise-like scent. Others, like the yellow oyster mushroom, have a fruity aroma. The stems of the yellow variety, though, may be bitter to some people.
Mushrooms have an amino acid called glutamate. This gives mushrooms a strong umami flavor. Umami is categorized as the fifth taste, also referred to as savory. The other tastes are:
- Sour
- Sweet
- Bitter
- Salty
Umami flavor can help enhance foods that are low in sodium. This reduces the need to add more salt. This means that mushrooms make a great substitute for meat.
How to Prepare Oyster Mushrooms
You can find oyster mushrooms in farmers markets and grocery stores. Dehydrated oyster mushrooms can also be found in Asian grocery stores, but you don’t need to rehydrate them before cooking.
Oyster mushrooms can also easily be grown at home. You can find oyster mushroom growing kits sold through gardening websites and magazines, and seed catalogs.
Choose mushrooms that have a firm texture and even color. Refrigerate them in a paper bag. They’re best used within a few days but can be kept for a week in the fridge.
Mushrooms don’t freeze well and become mushy when defrosted, as they’re about 80% to 90% water.
Don’t wash or clean oyster mushrooms until just before you’re ready to use them. Cut off the lower part of the stems and discard them. If you are using wild mushrooms, thoroughly rinse the gills to flush out any insects. Gently press the mushrooms between cloth or paper towels to get rid of extra water.
How to Cook Oyster Mushrooms
You can cook oyster mushrooms in a variety of styles, such as sautés, stir fries, and soups. If adding to a dish that needs long cooking time, add the oyster mushrooms at the last stage of cooking.
Oyster mushrooms are versatile and go well with all kinds of meats like poultry, seafood, fish, and red meat. They also taste great on their own when roasted whole.
Try oyster mushrooms in dishes like:
- Mushroom chowder
- Oyster mushroom tempura
- Scrambled eggs with oyster mushrooms
- Stir fried oyster mushrooms with tofu, minced ginger and garlic
- Sautéed in butter and cream, then added to pan-fried chicken