The Complete Guide to King Oyster Mushrooms

King oyster mushrooms are edible fungi known for their seafood-like flavor and meaty texture. But many people might not know these delicious mushrooms also have significant health benefits, such as reducing cholesterol levels and helping with diabetes.

We’ve done our best to gather all the information you need to know about king trumpets—from understanding their health benefits and picking them out at the grocery store (or out in the wild) to cooking with them for a delicious meal.

What are king oyster mushrooms?

The king oyster mushroom, scientifically known as Pleorotus eryngii (also sometimes spelled as Pleurotus eryngii), is an edible fungus native to Europe, Asia, and Africa. It’s one of the biggest species in the oyster mushroom family—a group of fungi named after their lack of stipe.

The king trumpet is one of the most popular mushroom choices in the world, partly due to its fantastic flavor but also due to its lax growth conditions. It has several different nicknames, which include:

• King trumpet mushroom
• Boletus of the steppes
• French horn mushroom
• Trumpet royale

P. eryngii naturally grows on the buried roots of hardwoods such as maples, willows, and beeches. The size of each specimen will mostly depend on the amount of nutrients each tree can provide. This makes it a highly adaptable mushroom and an ideal starting point if you want to grow your own mushrooms at home (1).

Most fungi lovers agree that king oyster mushrooms taste like seafood (specifically like abalone or scallops) due to their savory umami flavor. They also have a chewy, meaty texture that makes them the ideal choice for anyone looking to replace meat and other animal-based products.

However, not many people know that king trumpet mushrooms can also be highly beneficial for human health. Researchers suggest these delicious fungi have cholesterol-lowering, antidiabetic, and antiobesity properties (2) (3).

How do king trumpet mushrooms look?

King oyster mushrooms are the largest species in the oyster fungi family, with a 3–12 cm (1.1–4.7 in) cap and a 3-10 cm (1.1-3.9 in) white stem. The cap’s edges are initially convex, later flattening down until they start rolling inwards—which gives king oysters their characteristic funnel look. The grey gills are thin and distant from each other.

Usually, cultivated king trumpets grow larger than wild-picked ones. In nature, you can find this species growing alone or in small groups of a handful of specimens. Its spore print is completely white (1).

What are the varieties of king oyster mushrooms?

There are at least five varieties of king oyster mushrooms, although the literature is rather limited and hard to access. As such, it’s hard to tell exactly what distinguishes these strains from each other. The five recognized varieties are:

• P. eryngii var. eryngii
• P. eryngii var. ferulae
• P. eryngii var. tingitanus
• P. eryngii var. elaeoselini
• P. eryngii var. nebrodensis

From what we could gather, the varieties mostly have to do with where the species grows. For example, the traditional P. eryngii var. eryngii is closely linked to king oysters growing in France while P. eryngii var. Nebrodensis is associated more with Sicily in Southern Italy (4).

We know this can be a little confusing—but not to worry. No evidence suggests that these varieties have significant differences when it comes to nutritional or therapeutic properties Still, oyster mushrooms are one of the biggest families in the edible fungi world, encompassing unique species such as pink oysters and Indian oysters, so you’ll find some variations in flavors, nutritional values, and health benefits.

History of king oyster mushrooms

Experts theorize that king oysters go way back in history. While the first official mention of the species only dates back to the 1800s, there’s evidence to support that some ancient American and Asian cultures used these fungi.

A comprehensive review released in 2000 states that Ancient Mexicans, for example, were frequent consumers of oyster mushrooms. Mexicans have over 100 different nicknames for the species of the oyster family and commonly use them to treat sexual dysfunction and constipation. As such, it’s not crazy to think that king oysters were a part of the Aztecs’ menu (5).

Similarly, there’s some evidence to support Ancient Egyptians using all manner of mushroom for their medicinal properties and culinary value. At the time, they believed that mushrooms were a gift of the gods—an absolute delicacy reserved only for the highest of nobles (6).

The first official mention of the species dates back to 1815 when Swiss botanist Augustin Pyramus de Candolle first described it. Later, it was revised by the famous mycologist Elias Fries—although we couldn’t find the exact date of the revision.

Experts state that mass production of king oyster mushrooms (and many other species of the oyster family) began during World War I. Due to the greater demand for food, mycologists started working on highly effective cultivation techniques for Pleorotus species, allowing them to be distributed all around the world (7).

Health benefits of king oyster mushrooms

Like many of the other mushrooms we’ve covered, king oysters are a perfect example of functional fungi—species that have nutritional and health benefits. Researchers have found that king trumpets are excellent sources of cholesterol-lowering, antidiabetic, and antiobesity properties.

A typical serving of king trumpets will be mostly composed of crude protein, fiber, and carbohydrates, with very little fat. This makes them a good choice for vegetarians looking for new protein sources that don’t come from animals. Plus, P. eryngii contains several micronutrients, such as zinc, magnesium, potassium, and calcium (8).

As for the health benefits, research points out that king trumpets may lower both blood cholesterol and body fat levels in metabolically unhealthy patients. Participants reported noticeable improvements after just three months of eating king oysters daily. Furthermore, they also reported feeling better overall—possibly due to the mushrooms’ antioxidative and anti-inflammatory properties (3).

A 2011 study further supports using king trumpet mushrooms for lowering cholesterol and even suggests them for managing atherosclerosis—a condition where the arteries get clogged by plaques (2).

More recent preliminary research points out that king trumpets may even be useful for treating certain neurological disorders. While the mechanisms behind it aren’t clear, experts theorize that the species may interact with specific genes that could prevent neurodegenerative processes (9).

Where do king oyster mushrooms grow?

It’s common to find king oysters in Asian, European, and North African countries—although they seem more prevalent in Italy and the Mediterranean French coast. Usually, they grow on the buried roots of hardwoods, near Apiaceae trees, or as a parasite to thistle plants (particularly the European Eryngium campestre).

However, one of the main reasons why king oysters are so widespread is that they’re pretty easy to cultivate. Unlike other mushrooms, these fungi don’t require you to be very strict about their growing conditions, and they can yield up to 0.5 kg (1 pound) after a single 45-day cycle.

This makes it one of the top choices for people looking to grow their own mushrooms at home. Experts recommend inoculating a vertical hardwood log with plug spawn and letting the species run its course. After only a few weeks, you’ll have a delicious batch of king oysters to enjoy! (1) (10)

What is ethical wildcrafting?

Ethical wildcrafting refers to harvesting natural resources in a way that doesn’t harm the environment, including local mushroom and animal species. Wildcrafting is often confused with foraging, but the key difference is that the first refers to harvesting for medicinal purposes and the latter for culinary reasons.

If you’re new to the fungi world, or you’ve never gone wildcrafting, we recommend you take some time to learn the basics of ethical wildcrafting. Be sure to follow these simple guidelines:

• Do some research before heading out and take note of any endangered or poisonous lookalikes in your area
• Carry a field guide whenever you’re out harvesting
• Don’t take more mushrooms than you need—and don’t disclose patch locations with others as it could lead to overharvesting
• Pick the mushrooms gently, and only use scissors or knives if it’s absolutely necessary
• Request permission from the landowner, if wildcrafting on private property
• Check local regulations on harvesting, if wildcrafting on public land

If you don’t know where to start, we recommend you look for local harvesting group and forums. More experienced mycologists will gladly show you the ropes if you’re willing to learn. Plus, they will help you avoid dangerous lookalikes.

Is it safe to wildcraft for king trumpet mushrooms?

No matter the species, it’s never 100% safe to eat wild-picked mushrooms. A lot of mushrooms have poisonous lookalikes that can fool even the most experienced mycologist. In the case of P. eryngii, the most dangerous one is Inosperma erubescens—a deadly species that can sometimes look almost identical to P. eryngii’s.

Even if you’re absolutely sure that you’ve picked the right species, wild mushrooms can sometimes carry toxins from the environment. These can lead to gastric discomfort and pain—and there’s no guarantee that cooking the fungi will thoroughly get rid of them.

How do you take king oyster mushrooms?

There isn’t a specific way to cook king oyster mushrooms—like most fungi, this species is known for its versatility both as a side dish or as an ingredient for other recipes. King trumpets are popular in Asian cuisines as well as Italian. For some home cooks, these fungi might be the best vegan meat substitute (especially as vegan scallops), while others may use them to top salads or pizzas.

Here, we sharing some of our favorite king oyster mushroom recipes so you can enjoy all the benefits of these fungi in a delicious way.

Pan-fried king oysters: Preheat an iron skillet, add some oil, and throw in the mushrooms after you’ve cut them in halves. After three minutes, add salt and black pepper and continue cooking for about five more minutes. Finally, turn down the heat and add butter (or vegan butter), lemon juice, shallots, and a few cloves of garlic—after everything is cooked, enjoy!

Fried king oyster mushrooms: Who doesn’t love vegan fried chicken? Just prepare some batter with flour, water, and spices, and coat the mushrooms thoroughly. Then, drop them in oil over medium-high heat and let them cook for a few minutes. You can even make them gluten-free with gluten-free flours.

King oyster stir-fry: Stir fries are a fantastic way to pack a lot of healthy ingredients in a single, easy-to-make recipe. Pick a few vegetables, nuts, and mushrooms, and chop them accordingly. Then, on a pan, add a tablespoon of olive oil and gradually add the ingredients, sauteing them according to their specific cooking times. That’s it! If you want to experiment further, add soy sauce (or other sauce) to taste along with mushrooms like shiitakes or portobellos.

King oyster mushrooms: The royalty of the forest

King oysters are a top choice among mushroom lovers worldwide. Their meaty texture and seafood-like flavor make them the perfect substitute for meat and a delicious ingredient for almost any recipe. Plus, they’re very easy to cultivate at home.

If you want to find out about other types of mushrooms, keep up on shroomer. Here, you’ll find all the details you need about psychedelic and functional fungi from all over the world, along with the latest news on medicinal research on edible mushrooms.

References

1. Paul Stamets, “Pleurotus eryngii” in Growing Gourmet and Medicinal Mushrooms (1993), 304–308.
2. Nuhu Alam, Ki Nam Yoon, Jae Seong Lee, Hae Jin Cho, Mi Ja Shim, and Tae Soo Leea. “Dietary effect of Pleurotus eryngii on biochemical function and histology in hypercholesterolemic rats.” Saudi Journal of Biological Sciences, 18(4) (2011): 403–409. https://doi.org/10.1016/j.sjbs.2011.07.001
3. Kleftaki, S. A., Amerikanou, C., Gioxari, A., Lantzouraki, D. Z., Sotiroudis, G., Tsiantas, K., Tsiaka, T., Tagkouli, D., Tzavara, C., Lachouvaris, L., Zervakis, G. I., Kalogeropoulos, N., Zoumpoulakis, P., & Kaliora, A. C. “A Randomized Controlled Trial on Pleurotus eryngii Mushrooms with Antioxidant Compounds and Vitamin D2 in Managing Metabolic Disorders.” Antioxidants (Basel, Switzerland), 11(11) (2022): 2113. https://doi.org/10.3390/antiox11112113
4. Alma E Rodriguez Estrada, Maria Del Mar Jimenez-Gasco, Daniel J Royse. “Pleurotus eryngii species complex: sequence analysis and phylogeny based on partial EF1α and RPB2 genes.” Fungal Biology, 114(5-6) (2010): 421–428. https://doi.org/10.1016/j.funbio.2010.03.003
5. Gaston Guzman. “Genus Pleurotus (Jacq.: Fr.) P. Kumm. (Agaricomycetideae): Diversity, Taxonomic Problems, and Cultural and Traditional Medicinal Uses.” International Journal of Medicinal Mushrooms, l(2) (2000): 95–l23. http://dx.doi.org/10.1615/IntJMedMushr.v2.i2.10
6. Adel F. Ahmed, Ghada Abd-Elmonsef Mahmoud, Mohamed Hefzy, Zhenhua Liu, and Changyang Ma. “Overview on the edible mushrooms in Egypt.” Journal of Future Foods 3 (2023): 8–15. https://doi.org/10.1016/j.jfutfo.2022.09.002
7. Kamil Piska, Katarzyna Sułkowska-Ziaja, Bożena Muszyńska. “Edible mushroom pleurotus ostreatus (Oyster mushroom) – Its dietary significance and biological activity.” Acta Sci. Pol. Hortorum Cultus 16(1) (2017): 151–161. https://www.researchgate.net/publication/314664059_Edible_mushroom_pleurotus_ostreatus_Oyster_mushroom_-_Its_dietary_significance_and_biological_activity
8. D. Krüzselyi, D. Kovács, J. Vetter. “Chemical Analysis of King Oyster Mushroom (Pleurotus Eryngii) Fruitbodies.” Acta Alimentaria, 45(1) (2016): 20–27. http://dx.doi.org/10.1556/066.2016.45.1.3
9. Soumia Teniou, Abderrahmane Bensegueni, Brooks M. Hybertson, Bifeng Gao, Swapan K. Bose, Joe M. McCord, Benoît Chovelon, Chawki Bensouici, Ahcène Boumendjel, Isabelle Hininger-Favier. “Biodriven investigation of the wild edible mushroom Pleurotus eryngii revealing unique properties as functional food.” Journal of Functional Foods, 89 (2022): 104965. https://doi.org/10.1016/j.jff.2022.104965
10. MycoCosm. “Pleurotus eryngii ATCC 90797 v1.0.” No date. https://mycocosm.jgi.doe.gov/Pleery1/Pleery1.home.html