Oyster Mushrooms are some of the most widely consumed mushrooms in the world, along with button and shiitake mushrooms.
There are several varieties of oyster mushrooms with different characteristics and colors and everyone has their favorites.
King oysters, the largest of the oyster mushrooms, are unique and popular with chefs worldwide for their size, flavor and texture.
In this article, discover everything you need to know about king oyster mushrooms, including what they taste like, their health benefits and how to clean, store and cook them with easy recipes.
What is a King Oyster Mushroom?
A king oyster mushroom is a delicious edible mushroom with a thick stem and thin, flat cap. Often the stem is nearly as wide as the cap.
King oyster mushrooms have several English names, including king trumpet, royal trumpet, French horn and scallop mushrooms.
And, if you’re wondering, why is it called king oyster mushroom? There are a couple of reasons.
Firstly, when it comes to flavor and texture, many consider the king oyster superior to other oyster mushrooms.
And flavor and texture are not the only things that make them superior. They’re also the largest species of oyster mushrooms.
Although king oysters and other oysters are part of the same genus or family, Pleurotus, they’re different species.
Oyster mushrooms (Pleurotus ostreatus) grow in clusters and have short stems with oyster-shaped caps.
There are several different varieties with a range of colors, including gray, pearl, pink, blue and yellow oysters.
These easy-to-grow mushrooms are a popular choice for mushroom cultivators worldwide. Pearl oysters and phoenix oysters are the varieties most commonly cultivated.
King oysters (Pleurotus eryngii) are different. They grow individually and have defined, thick, white stems and small tan-colored caps.
But, their appearance can vary substantially depending on how they’re grown.
When cultivated indoors with less fresh air and low light, king oysters grow tall, fat stems with tiny caps.
But in the wild, with lots of fresh air and light, they have smaller stems and larger caps and look more like Pleurotus ostreatus oyster mushrooms.
What Does King Oyster Mushroom Taste Like?
While everyone agrees that king oyster mushrooms are unique, delicious and intensely umami, people describe their taste differently.
To most, they taste earthy, woody and slightly nutty, while others describe them as savory and meaty with seafood-like flavors.
Those who find them somewhat like seafood compare their taste and texture to scallops, calamari or abalone.
And some people have even detected subtle anise or licorice flavors in their king oyster mushrooms.
Does King Oyster Mushroom Taste Like Meat?
King oyster mushrooms have a meaty texture and, depending on how you cook them, can sometimes taste like mild-flavored meats.
Because they retain their texture well when cooked, vegans often use them as a substitute for scallops, and when crispy fried with a crunchy coating, they taste similar to chicken.
But, to appreciate their mushroomy flavor, it’s best to saute them. Like other oyster mushrooms, sauteeing brings out their unique earthy flavors.
Can You Eat The Whole King Oyster Mushroom?
Yes, you can eat the whole king oyster mushroom, and unlike many other gourmet mushrooms, people prize king oysters for their stems, not their caps.
Their stems are possibly the meatiest of all mushrooms. When sliced horizontally, they look so similar to scallops that people sometimes refer to them as “vegan scallops.”
Can You Eat King Oyster Raw?
Technically you can eat king oyster mushrooms raw, but this is not the best way to enjoy them, and they’re usually not served raw.
Some mushrooms, like enoki, taste good eaten raw or cooked. But, raw king oysters have little flavor other than being slightly metallic, and are tough and hard to chew.
Cooking brings out their delicious umami flavors and also makes them more nutritious.
The heat helps break down their cell walls, releasing nutrients and medicinal compounds.
How to Cook King Oyster Mushrooms
Because of their size and texture, king oyster mushroom stems are exceptionally versatile, and people often use them as a meat substitute.
Prized by Asian chefs, they’re a popular ingredient in Chinese, Japanese and Korean cuisine.
There you’ll find them in stir-fries, fried in tempura batter and served with dipping sauces, or skewered whole and grilled.
In other places, people use king oysters to make tasty barbecue skewers, vegetable casseroles, and pasta sauces.
And, as they keep their shape and meaty texture when cooked, they work well in dishes with longer cooking times like soups and stews.
When sliced lengthways, king oyster mushroom stems are perfect for the grill. Baste them with soy or barbecue sauce and grill them until they’re golden brown.
King Oyster Mushroom Recipes
There are loads of delicious oyster mushroom recipes for you to try, and many of them are quick and easy.
And, although king oysters absorb other flavors well, we like to savor their unique flavors. So king oysters sauteed with a touch of butter are our favorite.
Below are a couple of easy recipes to get you started, and for more inspiration take a look at “30 of the best mushroom recipe ideas.”
Sauteed King Oysters with Butter
This recipe, adapted from Great British Chefs, highlights the umami flavor of the king oyster mushrooms and is quick and easy to make.
Serve these sauteed king oysters with eggs for a luxurious breakfast treat or as part of a nutritious autumn salad with leafy greens, rocket and tomato.
Ingredients
- 2 king oyster mushrooms
- Olive oil
- 1.4 oz (40g) of unsalted butter, cubed
- 1 sprig of thyme (optional)
- 1 garlic clove, bashed (optional)
- Flaky sea salt
Instructions
- Clean and slice the king oysters in half lengthways. Then lightly score a 5mm diagonal criss-cross pattern into the cut side of the mushrooms to help them cook more evenly and absorb the seasoning better.
- Heat a pan over high heat. Once the pan is almost smoking hot, add a drizzle of olive oil and place the mushrooms in the pan cut-side down. Turn the heat down to medium-high
- Cook the mushrooms until they turn a nice golden color, around 3 to 5 minutes, depending on the size of your mushrooms.
- Add the butter to the pan and let it melt. Then add the thyme and garlic and season with salt.
- Turn the mushrooms over and baste with the foaming butter while they finish cooking.
- Drain, sprinkle with sea salt and serve hot.
Garlicky King Oyster Mushroom Scallops
This king oyster scallops recipe, adapted from Loving It Vegan, makes a tasty appetizer or main course. The delicious garlic and butter sauce is always a hit and compliments the mushrooms’ umami flavor.
To make this a vegan mushroom recipe, simply substitute the butter with vegan butter.
Ingredients
- 1 pound (450g) of king oyster mushrooms
- 1 tablespoon olive oil plus a little more for brushing
- ¼ teaspoon sea salt
- ¼ teaspoon ground black pepper
- ⅛ teaspoon paprika
- 4 tablespoons butter or vegan butter
- 3 cloves garlic, crushed
- 1 tablespoon freshly-squeezed lemon juice
- 2 tablespoons chopped parsley
Instructions
- Clean your mushrooms, cut the ends off the stems and slice them horizontally into 1-inch (2.5cm) thick discs.
- Place the mushroom slices on a baking tray and brush them with olive oil. Then turn them over, brush the other side with olive oil and season with salt, black pepper and paprika.
- Coat a cast-iron skillet with a thin layer of olive oil and preheat it over medium-low heat. Add some mushroom slices to the hot skillet, seasoned side down.
Make sure not to overcrowd the pan. There should be spaces between the slices, and none of them should overlap.
- While the first side is searing, season the other side with salt, black pepper and paprika. Cook for around 2 minutes, and then flip the mushroom slices over. The seared side should be golden brown.
- Cook the other side for around 2 minutes, until golden brown, then return the scallops to the baking tray.
Repeat steps 3 to 5 with the rest of the mushroom slices, adding more oil if needed until they’re all seared and golden brown.
- Add your butter or vegan butter and crushed garlic to the same skillet and let them cook for around 1 minute until fragrant.
- Add lemon juice and parsley to the pan and turn off the heat. Put all the scallops back into the pan and gently move them around to coat them with sauce.
- Serve your king oyster mushroom scallops with chopped parsley and lemon slices.
Where to Buy King Oyster Mushrooms
Depending on where you live, you may be able to buy fresh king oyster mushrooms at your local grocery store or farmer’s market.
Because king oysters are usually grown indoors, they’re available year-round, and you’ll often find them in larger supermarket chains, Asian grocery stores or specialty produce stores.
Try to find a supplier nearby to ensure you get the freshest possible king oyster mushrooms and select mushrooms with firm, smooth stems and caps.
Wrinkled or slimy mushrooms or mushrooms with dark spots have passed their prime. They won’t last long and may go bad quickly once you get them home.
In some areas, you can order king oysters online from local mushroom farmers who’ll deliver fresh king oysters to your door.
If you’ve tried the options above and cannot source fresh king oysters (or just prefer the freshest possible mushrooms), we recommend growing your own mushrooms at home.
Where to Find King Oyster Mushrooms in the Wild
King oyster mushrooms are widely cultivated, but if you want to find king oysters growing in the wild, you’ll have to visit the Mediterranean regions of Southern Europe, Russia, Central Asia and North Africa.
There you’ll find king oyster mushrooms growing on the roots of dead or decaying deciduous trees.
Unlike other oyster mushrooms, king oysters are not only saprotrophic, meaning they feed on dead and dying organic matter, but sometimes also slightly parasitic on the roots of herbaceous plants.
The fruiting temperatures for king oysters are 59 to 65°F (15 to 18°C) with humidity levels of 80% to 90%, which means you’ll usually find them emerging from the soil in autumn and early winter.
How to Grow King Oyster Mushrooms
Oyster mushrooms are one of the easiest mushroom species to grow, and we recommend them for beginner mushroom growers.
Although king oysters are slightly fussier and take a little longer than the Pleurotus ostreatus species, they’re still popular with small-scale mushroom cultivators.
You can grow king oysters indoors in bags of substrate or outdoors in mushroom beds.
Like other oysters, king oyster mushrooms will grow on low nutrient, cellulose-rich substrates like straw or sugar cane bagasse.
But, you’ll get much better yields when using a mushroom substrate with more nutrients like supplemented sawdust blocks or master’s mix.
The easiest way to grow king oysters is with a ready-to-fruit mushroom growing kit.
These contain a fully colonized substrate block that’s ready to fruit. Simply open your kit, place it in a spot with indirect light and good airflow and mist it with water once or twice a day.
People who live in extreme climates may have to use a fruiting chamber to help maintain fruiting conditions.
Monotubs, shotgun fruiting chambers and Martha grow tents are all inexpensive, DIY fruiting chambers and perfect for fruiting king oysters.
If you have some mushroom growing experience, you can buy king oyster mushroom spawn, prepare bulk substrate and make your own fruiting blocks.
One of the fun things about growing king oyster mushrooms is that by altering the growing conditions, you can produce different-looking mushrooms.
For example, if you open the top of your bag without folding it back, the space between the top of the substrate and the top of the bag will trap CO2.
The higher levels of CO2 will result in king oysters with thicker stems and smaller caps.
You can also decide when to harvest your king oyster mushrooms and baby king oysters as are popular with chefs as mature king oysters.
How Long Does it Take King Oysters to Grow?
If you’re using a grow kit, you could have ready-to-harvest king oysters within two weeks of opening your kit.
Mushroom pins will start forming on the surface of the substrate in around 4 to 8 days, and over the next week, they’ll increase in size daily.
If you’re growing king oysters from scratch, allow an additional 10 to 14 days for incubation while your king oyster mushroom spawn colonizes the bulk substrate.
Our article, “How Long Does It Take To Grow Mushrooms? All Questions Answered,” has more information on these timelines.
Can You Grow King Oysters in a Bucket?
Yes, you can grow king oysters in a bucket, but they’re not recommended for this cultivation method as they’re predominantly a top-fruiting mushroom species.
In the wild, king oysters grow on the ground and not on the sides of logs like side-fruiting oyster mushroom species.
If you want to grow king oysters in a container instead of bags, then a monotub is a good option as this caters to top-fruiting mushrooms.
If you grow king oysters in a bucket, they’ll grow out the holes in clusters like other oyster mushrooms and will not have the same characteristic, thick stems.
How to Clean and Prepare King Oyster Mushrooms
King oyster mushrooms are one of the easier mushrooms to clean and prepare, thanks to their large, defined stems.
Most cultivated king oysters grow indoors in bags, with little to no dirt and debris. All that’s needed to clean them is a gentle brush or quick wipe with a damp kitchen towel.
However, if you harvest wild king oysters or grow them outdoors, you may want to give them a quick rinse under running water and pat them dry with a paper towel.
Only rinse your mushrooms just before you plan on using them, as washing can shorten their shelf life.
Once clean, trim off the bottom of the stem and then slice or chop your king oysters to suit the dish you’re preparing.
Recipes often use king oysters halved or sliced lengthways, sliced into rounds for scallops or chopped into smaller pieces for casseroles and pasta sauces.
Our article on how to clean mushrooms has more information for you.
How to Store King Oyster Mushrooms
Unless you are lucky enough to find king oysters loose at a farmer’s market, they’ll usually come in plastic packaging.
You can store them in your fridge in this packaging for a few days. But first, poke a few holes in the plastic so excess moisture can escape and the mushrooms can breathe.
But, if you need to store your king oysters longer, a loosely closed paper bag on a shelf in the fridge, not in the crisper drawer, is the best way to extend their life.
How long do king oyster mushrooms last? When stored correctly in the fridge, king oysters last longer than most other types of mushrooms.
The average shelf life of other oyster mushrooms is 2 to 7 days, while king oysters last an average of 10 days in the fridge and in ideal conditions can last more than two weeks.
Health and Nutritional Benefits of King Oyster Mushrooms
King oyster mushrooms are not only delicious, but they’re also full of beneficial nutrients and medicinal compounds.
Like other oyster mushrooms, king oysters are fat-free, low in cholesterol and sodium, high in protein and fiber and low in carbs making them valuable as part of a keto diet.
They’re a good source of riboflavin, niacin, pantothenic acid, phosphorus, potassium, copper, thiamin, vitamin B6, folate, iron, magnesium, zinc and manganese.
King oysters are also full of antioxidants and, even when cooked, contain large amounts of the amino acid L- ergothioneine, a potent antioxidant.
The beneficial compounds in king oysters help humans maintain good health by activating our immune systems, and studies show they have potential anticancer and antiviral benefits.
Our article on the health benefits of oyster mushrooms has more information for you.
Final Thoughts
King oyster mushrooms are large, meaty and delicious. As a result, people often use them as a meat substitute in vegan meals.
Another thing that makes them popular is that they last longer in the fridge than most other mushrooms.
Depending where you live, you may find fresh king oyster mushrooms at your local farmer’s market, Asian grocery stores or specialty produce stores.
If you can’t source fresh oyster mushrooms locally, the good news is that they’re relatively easy to grow at home, both indoors and outdoors.
To learn more about growing oyster mushrooms, visit our Mushroom Growing Hub or enroll in one of our online mushroom cultivation courses.