What You Should Know
Boletus edulis is a mushroom that has pores instead of gills and is the type species of the Boletus genus. It is large and can be yellow-brown to reddish-brown in color. It grows under various trees, such as conifers, birches, oaks, and beeches, and can be found all over the world. This mushroom is highly valued for its taste and texture, but can be difficult to find since it often grows hidden beneath the soil surface. Experienced hunters look for small humps in the litter as indicators of the mushroom's presence.
It is also a popular ingredient in many cuisines and is used in various dishes such as soups, sauces, and risottos. Moreover, the nutritional value of Boletus edulis is noteworthy, as it is a good source of protein, fiber, and various minerals and vitamins such as copper, potassium, and vitamin B12. However, it is important to note that while Boletus edulis is generally considered safe to eat, there are some poisonous look-alike species, so it is important to be able to properly identify the mushroom before consuming it.
The largest Boletus edulis mushroom ever recorded was found in Poland, weighing a whopping 6.6 lbs (3 kg). This massive porcini mushroom was in excellent condition, with firm flesh and a delightful fragrance, and was free of any signs of infestation.
Other names: King Bolete, Penny Bun, France (Cèpe de Bordeaux), Spain (Rodellon), German (Steinpilz), Czech Republic (Hřib smrkový), Estonia (Puravikud) Dutch (Eekhoorntjes Brood), Netherlands (Gewoon eekhoorntjesbrood).
Boletus edulis Mushroom Identification
The cap is 1.97 to 7.87 inches (5 to 20 cm) in diameter, fleshy, initially hemispherical, later convex-spread, pillow-like, spread, flat-spread. The surface is initially pubescent, later smooth, slightly wrinkled, matte, slippery in wet weather, shiny, yellowish-brown, chestnut-brown, dark brown, grayish-brown, and does not change color in places of contact.
The hymenophore is tubular. Pores are small, rounded, initially whitish, grayish, with age yellow-green, yellow-olive.
The stem is 1.97 to 7.87 inches (5 to 20 cm) high, 0.79 to 2.76 inches (2 to 7 cm) in diameter, initially bulbous, later club-shaped, expanded to the base, longitudinally wrinkled, dense, fleshy, solid, white, grayish, grayish-brownish, ocher, light brown.
White slightly yellowing with age.
Spores 12-19 * 4-6 μm, spindle-shaped, rarely elongated.
Odor and Taste
The taste and smell are very mushroomy, one of the best species to dry where the mushroom flavor is enhanced.
King boletes are a type of fungus that grow in a mycorrhizal association with trees, particularly hemlock, oak, spruce, and other conifers. They can also be found in lawns and grassy areas under conifers. They are most abundant from June to October in forests of all types, especially in young spruces or at their edges, and can grow at various elevations. They can also grow outside the forest wherever the roots of trees reach, forming a symbiotic relationship with the trees.
Boletus edulis Look-Alikes
Looks very similar but has a slightly darker stem, not as solid flesh, lacks the white cap edge and grows in early Summer.
Has a strongly bitter flesh, the tubes of which gradually turn pink.
Has a reddish tint on the cap skin.
Usually darker, with olive or bronze hues. It is a thermophilic species forming a mycorrhiza with oaks on calcareous soils.
Boletus edulis Time-Lapse
Boletus edulis Cultivation
Boletus edulis is parasitic mushroom it means that when an organism lives on another living creature without giving it any support, or rather getting it sick or killing it.
On the contrary, symbiosis happens to be a mutual or mychorrizal process when it consists of an exchange of nutritional favors.
As a result, an intimate link between mushroom and host plant gets established, so that you can cultivate this type of mushroom only if it is close to its plant.
For this reason, it is quite difficult – if not impossible – to cultivate a mychorrizal mushroom.
A very common example of symbiont is truffle, which is cultivated on mychorrizal plants.
Following the same procedure, the cultivation of boletus has also been pursued by mychorrizing host plants.
Can You Eat Boletus edulis Raw?
Boletus edulis is one of the few wild mushrooms that can be served raw. The literature will often advise against this, and you certainly want to be moderate when eating any kind of mushroom for the first time.
Slices of raw fresh porcini buttons are sweet and delicious, but it is highly unlikely that you will ever find these unless you are picking them in the forest yourselves. Porcini that is passed the ‘button’ stage or that is more than a day or two old will be less sweet and spongy.
Mature mushrooms are delicious when cooked and can be dried.
Recipe: Grilled Porcini Mushrooms with Mint and Garlic
1 teaspoon minced flat-leaf parsley leaves
1 teaspoon minced thyme leaves
1 teaspoon minced rosemary leaves
1 teaspoon minced mint leaves
2 cloves garlic, minced
1/3 cup extra-virgin olive oil, plus more for brushing
1 pound porcini mushrooms (about 6 medium)
Light a medium fire in a charcoal grill.
In a small bowl, stir together the herbs, garlic, and 1/3 cup olive oil.
Clean the mushrooms with a damp cloth. If desired, cut the mushrooms into 1/2-inch-thick slices and lightly brush them with oil. Grill until lightly browned, about 3 minutes per side. Transfer to a serving platter and brush with the herb-oil mixture. Serve at once.
Recipe: Tagliatelle with Boletus edulis Mushrooms
400 g tagliatelle (14oz) fresh or dried
500 g of fresh or frozen porcini mushrooms (17oz) See recipe notes about using dried porcini
½ glass white wine
3-4 fresh nepitella small leafed wild mint sprigs or thyme
2-3 tbsp extra virgin olive oil
2 garlic cloves peeled
2 tbsp unsalted butter
salt and pepper to taste
grated parmesan for serving
Put water on to boil for the pasta. Add salt once it starts to boil.
Clean the mushrooms by cutting off the end of the stalk. It would be better not to rinse with water, given that the fungus absorbs it. You can use a small brush to remove any soil, or a damp cloth.
Cut the mushrooms into pieces
Fry the peeled garlic cloves in the olive oil, then remove them when golden and add the mushrooms.
Cook them for about 3-4 minutes.
Add wine and nepitella or thyme, increase the heat and cook until the alcohol has evaporated
Reduce the heat and add salt and pepper.
Continue to cook for about another 10-15 minutes. Remove from the heat once mushrooms are cooked through and add the butter.
Cook the pasta in salted boiling water, remove a glass of the pasta cooking water to be used later and then drain and add the pasta to the pan with the mushrooms and butter.
Toss everything together. The pasta absorbs liquid very quickly so if it looks too dry, add a little of the pasta cooking water at a time until you get the right creaminess.
Serve immediately with grated parmesan as required.
Using dried porcini
Because dried porcini have a very strong taste and are expensive, we suggest mixing them with some cremini or white champignon/button mushrooms. That way you also get nice pieces of mushroom in the sauce. 60g (2oz) dried porcini & 400g (14oz) other mushrooms.
Soak the dried porcini in bowl of warm water for about 30 minutes before draining and cooking (the water should cover the mushrooms). You can use a bit of the soaking liquid in the sauce.
Recipe: Pappardelle with Lemon, Garlic and Porcini Mushrooms
455g pappardelle pasta (if you can’t get hold of pappardelle, linguine works well too)
Juice of half a lemon
60g parmesan cheese, grated
2 garlic cloves
25g Merchant Gourmet Dried Porcini mushrooms
1 small glass white wine
300g fresh chestnut mushrooms, sliced
Handful parsley, chopped
Place the Porcini Mushrooms in a small bowl, cover with boiling water and leave to rehydrate for 15 minutes.
Melt the butter in a frying pan, and fry the chestnut mushrooms on a moderate heat for 3 minutes.
Lift the rehydrated Porcini Mushrooms from the bowl and fry with the chestnut mushrooms for 2 minutes.
Peel, and finely slice the garlic and add to the pan with a few grinds of salt and pepper.
Stir the mushroom from time to time allowing them to go nicely golden.
Bring a large pan of salted water to the boil and cook the pasta according to pack instructions.
Place the wine and half of the mushroomy water into the frying pan, and allow to simmer on a gentle heat.
When the pasta is ready, drain and add to the mushrooms.
Throw in the parsley, parmesan and fresh lemon juice, and toss so that all the pasta is nicely covered. Serve.
Recipe: True Italian Porcini Mushroom Risotto
1 ounce dried porcini mushrooms
1 cup hot water
1 (32 ounce) carton beef stock
¼ cup olive oil, divided
3 cloves garlic
1 teaspoon dried rosemary
salt and ground black pepper to taste
1 cup white wine, divided
¼ cup butter, divided
1 shallot, chopped
1 ¾ cups Arborio rice
⅓ cup grated Parmesan cheese
Place porcini mushrooms in a bowl and cover with hot water. Let soak until soft, about 1 hour. Drain, reserving soaking liquid. Squeeze mushrooms to remove excess water and roughly chop.
Bring beef stock to a boil in a saucepan. Reduce heat to low and cover to keep warm.
Heat 3 tablespoons oil in a skillet over medium heat. Add garlic cloves; cook until fragrant, about 2 minutes. Add mushrooms; cook and stir until soft, 5 to 6 minutes. Season with rosemary, salt, and pepper. Discard garlic cloves; pour in 1/2 cup wine. Increase heat to medium-high and simmer until wine reduces, 3 to 5 minutes.
Heat remaining 1 tablespoon oil with 2 tablespoons butter in a saucepan over medium-low heat. Cook and stir shallot until soft, about 3 minutes. Cook and stir Arborio rice until toasted and fragrant, about 3 minutes. Pour in remaining 1/2 cup wine. Simmer until wine is absorbed, about 3 minutes.
Ladle 1/3 of the warm stock into the saucepan; cook and stir until absorbed. Ladle in remaining stock and reserved soaking liquid in small amounts and cook, stirring constantly, until risotto is tender and creamy, 15 to 18 minutes.
Remove risotto from the heat; stir in remaining 2 tablespoons butter and Parmesan cheese. Let stand for 3 to 5 minutes before serving.
Boletus edulis Taxonomy and Etymology
In 1782 French botanist Pierre Bulliard described this species. Early alternate names include Boletus solidus by English naturalist James Sowerby in 1809, and Gray's Leccinum edule. Gray's transfer of the species to Leccinum was later determined to be inconsistent with the rules of botanical nomenclature, and he was unfamiliar with the earlier works of Fries when he published his arrangement of bolete species.
In Rolf Singer's classification of the Agaricales mushrooms, it is also the type species of section Boletus, a grouping of about 30 related boletes united by several characteristics: a mild-tasting, white flesh that does not change color when exposed to air; a smooth to distinctly raised, netted pattern over at least the uppermost portion of the stem; a yellow-brown or olive-brown spore print; white tubes that later become yellowish then greenish, which initially appear to be stuffed with cotton; and cystidia that are not strongly colored.
A molecular analysis published in 1997 established that the bolete mushrooms are all derived from a common ancestor, and established the Boletales as an order separate from the Agaricales.
The generic name is derived from the Latin term bōlētus "mushroom", which was borrowed in turn from the Ancient Greek βωλίτης, "terrestrial fungus". Ultimately, this last word derives from bōlos/βῶλος "lump", "clod", and, metaphorically, "mushroom". The βωλίτης of Galen, like the boletus of Latin writers like Martial, Seneca and Petronius, is often identified as the much prized Amanita caesarea.
The specific epithet edulis in Latin means "eatable" or "edible".
Boletus edulis Synonyms
Tubiporus edulis (Bull.) P. Karst
Boletus betulicola (Vassilkov) Pilát & Dermek
Boletus citrinus A. Venturi
Boletus clavipes (Peck) Pilát & Dermek
Boletus edulis f. albus (Pers.) J.A. Muñoz
Boletus edulis f. arcticus Vassilkov
Boletus edulis f. betulicola (Vassilkov) Vassilkov
Boletus edulis f. citrinus (Pelt. ex E.-J. Gilbert) Vassilkov
Boletus edulis f. citrinus J.A. Muñoz
Boletus edulis f. edulis Bull.
Boletus edulis f. laevipes (Massee) Vassilkov
Boletus edulis f. olivaceobrunneus (Zeller & F.D. Bailey) Vassilkov
Boletus edulis f. praecox Vassilkov
Boletus edulis f. pseudopurpureus (Murr) Vassilkov
Boletus edulis f. quercicola Vassilkov
Boletus edulis f. roseipes Vassilkov
Boletus edulis f. subaereus Vassilkov
Boletus edulis f. tardus Vassilkov
Boletus edulis subsp. betulicola (Vassilkov) Hlaváček [as 'betulicolus']
Boletus edulis subsp. clavipes (Peck) Singer
Boletus edulis subsp. edulis Bull.
Boletus edulis subsp. euedulis (Maire) Singer
Boletus edulis subsp. euedulis Maire
Boletus edulis subsp. slovenicus (Smotl.) Hlaváček
Boletus edulis subsp. trisporus Watling
Boletus edulis var. abietis Schiemek
Boletus edulis var. arcticus (Vassilkov) Hlaváček
Boletus edulis var. arenarius H. Engel
Boletus edulis var. betulicola Vassilkov
Boletus edulis var. citrinus Pelt. ex E.-J. Gilbert
Boletus edulis var. clavipes Peck
Boletus edulis var. communis Alb. & Schwein.
Boletus edulis var. edulis Bull.
Boletus edulis var. elephantinus (With.) Pers.
Boletus edulis var. elephantinus Massee
Boletus edulis var. laevipes Massee
Boletus edulis var. ochraceus A.H. Sm. & Thiers
Boletus edulis var. piceicola Vassilkov
Boletus edulis var. pseudopurpureus Murr
Boletus edulis var. quercicola Vassilkov
Boletus edulis var. quercus Schiemek
Boletus edulis var. tuberosus Pers.
Boletus elephantinus With.
Boletus esculentus ß albus Pers.
Boletus olivaceobrunneus Zeller & F.D. Bailey
Boletus persoonii Bon
Boletus quercicola (Vassilkov) Singer
Boletus reticulatus var. albus (Pers.) Hlaváček
Boletus reticulatus var. citrinus Hlaváček
Boletus slovenicus Smotl.
Boletus solidus Sowerby
Boletus solidus Sowerby (1809)
Boletus venturii Bon
Ceriomyces crassus Battarra (1775)
Dictyopus edulis (Bull.) Forq., 1886
Dictyopus edulis var. edulis (Bull.) Quél.
Leccinum edule (Bull.) Gray, 1821
Leccinum elephantinum (With.) Gray
Suillus citrinus (A. Venturi) Kuntze
Tubiporus edulis (Bull.) P. Karst.
Tubiporus edulis subsp. edulis (Bull.) P. Karst.
Tubiporus edulis subsp. euedulis Maire
Tylopilus porphyrosporus var. olivaceobrunneus (Zeller & F.D. Bailey) Wolfe
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