There are a few wild mushrooms which are highly sought after for culinary purposes. In time we will talk about all of them - truffles, chanterelles, morels, lobster mushrooms, horns of plenty ("trumpets of death"). But today we discuss what many consider the king of all mushrooms: Boletus edulis, most commonly known as the Porcini.
Most people have never tried hunting for wild mushrooms, let alone eating them. Nonetheless, Porcinis are well known all over the world. Their taste is universally acclaimed and, for many, their aesthetic is nothing less than the icon of the entire Kingdom of Fungi.
Take a look at that mushroom. Few specimens are as exciting and visually satisfying to find as a mature, undeteriorated Porcini, or one of its close cousins. B.edulis and B.edulis-like mushrooms grow all over the world. You can find these mushrooms from China, through Russia, across Europe and North Africa, and all the way across the ocean in North America and parts of Mexico. As long as you're in the northern hemisphere, you can find some variation of this mushroom in a forest near you from June through November.
Why do I say "nearly identical" and "B.edulis-like?" As with so much of mycology since the advent of DNA analysis, the old paradigms of B.edulis identification have changed. It used to be mycologists were satisfied referring to B.edulis as roughly one widespread species of the Boletus genus. However in the last decade, DNA analysis has again shown that what was once considered a single overarching species is actually a humongous diversity of genetically unique mushrooms.
As a result, if we're being technical, true B.Edulis species probably only grows in Europe, whereas the rest of the world has B.edulis lookalikes. Luckily, this distinction is mostly academic. For forest traipsing bolete hunters around the world it changes almost nothing. You might end up with a Boletus rex-veris, pictured below, instead of a B.Edulis, but you'll still be satisfied.
If you're hunting in North America and interested in discerning the exact species of a B.edulis type mushroom, you can use Michael Kuo's key to B.Edulis, or buy an identification book exclusively for boletes. However, for those of you less inclined to extreme detail, there are certain macro characteristics which can clarify if you're within the broad range of B.edulis-like species and variants.
First, as with every species of Boletus, the spore surface is porous.
If you cut the cap in half, you can see in the cross-section that the pores are in fact thin tubules meshed together to make a cohesive whole.
This pore surface starts out white, then becomes yellow with age, eventually turning olive brown. If you bruise the pores with your finger, they should not change color.
The cap of the mushroom is usually plump, convex when young and then flattening out in the older specimens, with the edges sometimes turning up to reveal the pore surface a bit. The cap can grow to nearly a foot in diameter, although most specimens will be less wide. The cap color of the true B.edulis is reddish brown and gets darker as the mushroom gets older. But several close relatives can be lighter in color.
The stem of B.edulis has as much character as the cap. Often wider at the bottom and tapering toward the top, it should have a consistent white flesh throughout when young. The height varies widely as well, from 3 inches up to 10 inches. Young mushrooms should be undifferentiated white flesh and firm, rather than spongy. When you cut the flesh it might discolor to brown or red.
One thing to look for in judging the quality of the mushroom is to bifurcate the stem and look for the bore holes of insects inside. Ideally the flesh should be white through and through - but often it will be cut through with insect tunnels. In that case, you can cut away the eaten parts and possibly salvage the remainder.
One of the great things about B.edulis and its variant and species is that there are, as far as I know, almost no inherently poisonous lookalikes. There is only one awesome looking, probably poisonous Boletus mushroom I know about, referred to "Satan's Bolete". We'll do a future post all about it, but as you can see here, it is all red on the underside and easy to distinguish.
update 1
update:
So i was reading a comment by 
I put this here to highlight **that i cannot be aware of every lookalike or make you aware of every lookalike. I'm sure there are more boletes which are in fact poisonous some of the time which i have not mentioned. It is with this in mind that i again encourage you to take these posts as an introduction to mushroom identification - a starting point from which to jump off and gain a more in depth and rigorous knowledge.
I think the risks/intentions may be worth a post all on ts own in the future.
There are four concerns with picking, cooking and eating B.edulis-like mushrooms:
- Making sure you don't have a poisonous bolete - like b.satanas or b.sensibilis. one method is to reject any boleteswhose flesh changes color, or at least turns blue.
- The possibility of a personalized allergic reaction - which of course can be serious and is almost impossible to predict.
- The possibility that the mushroom is growing on ground contaminated with heavy metals, which the mushroom absorbs into its flesh.
- The possibility of accidentally picking a species or variant which, although not poisonous, just isn't very palatable. There are tons of these - A good example would be the Tylopilus felleus mushroom, which looks very similar to B.edulis, but instead of being delicious, is terribly bitter.
The simplest way to tell the difference is either to taste the mushroom for bitterness, spitting out the taste without swallowing, or look for "reticulation" on the stem. Reticulation is a net-like pattern sometimes found on mushrooms, often on the stems. B.edulis-like mushrooms have a whitish pattern on a brownish stem - whereas T.felleus has a dark pattern on a white stem.
B.edulis and B.edulis-like mushrooms are renowned around the world as the some of the best edible wild mushrooms. If you want to try hunting for a feast, I would suggest connecting with your local mycological society or taking a mycological trip with trained mycologists to become familiar with the process in person. Until then, keep your eyes peeled for these marvelous Boletes.
Macroscopic Features:
Cap = Convex at first, then flattens as it gets older, ranging in size from 2.8 to 11.8in (7-30cm). Gets darker as it matures, generally reddish brown and lighter around the edges. A bit sticky to the touch, especially if wet.
Spore surface = fairly deep, whitish pores when younger, yellowing with age until finally ending almost light olive. The pores don't change color when damaged or pressed with a finger,
Flesh = White. Sometimes a bit of brown near the base of the stem. Firm when young, becoming spongy when older. Mixed reports about whether damage changes color of the flesh - wikipedia says possibly light brown or light red change. Boletales says no change. No distinct taste
Stem ("stipe") = 3.1 - 9.8in (8-25 cm) high and up to 2.8in (7cm) thick. Often club like, cylindrical but sometimes with a taper, sometimes bulbous or swollen looking. Reticulation on the exterior of the stem is well defined, fading near the bottom of the stem. White pattern on darker background. Bifurcation should show an undifferentiated white flesh through the stem.
Spore Print = Olive Brown
Ecology ("How it grows.") = Mycorrhizal (In a mutually beneficial symbiotic relationship) with certain trees - primarily conifers (sprice, fir and pines) as well as some deciduous tree - (beech and birch). Therefore will often be found by these trees.
Distribution = The genetically true B. Edulis may only really be in Europe. However, B.Edulis like mushrooms span the globe.
Edibility = The true B.Edulis is commonly considered the king of edible wild mushrooms. Highly sought after and very expensive to buy. The many B.Edulis lookalikes are similarly sought after, however do beware of poisonous or bitter lookalikes, like "Satan's Bolete" and Tylopilus felleus in your hunts.
Other Traits = Often B.Edulis like mushrooms will have bugs in their flesh, as bugs like to eat it as much as people. Cut away the buggy portion if the mushroom is not too old and it can still be harvested.
Disclaimer (Yes - A Bigger Disclaimer)
Since I've started to post these in the #foraging tag, I want to be clear about the risks of mushroom hunting. The fact is, hunting mushrooms as food is an inherently risky activity. These posts are species introductions intended to provide entertaining and edifying reading to readers unfamiliar with mushrooms. Do not rely on this, or any other Amateur Mycology post in deciding whether to eat a wild mushroom - use one of the many resources designed specifically, by professional mycologists to guide people in hunting and eating wild mushrooms.
As I frequently talk about, the entire Kingdom of fungi has been in flux since the advent of DNA analysis and as only an amateur mycologist, dealing only with macroscopic identification, my knowledge should be taken as introductory rather than comprehensive or encyclopedic - AND THESE POSTS SHOULD NOT BE USED TO IDENTIFY A MUSHROOM AND EAT IT. I could easily be wrong in identifying a species or describing a characteristic. Even trained mycologists have made mistakes and poisoned themselves in the course of their activities! As a result, I have and will continue to say in these posts that the safest approach is always going to be abstaining from eating your finds and, it goes without saying, you ingest wild mushrooms at your own risk.
Having said that, many people do take part in the hobby for foraging purposes, and doing so with an eye to detail and with a reasonable methodology is important. My hope in writing these posts is to inculcate good macro-identification habits in my readers and begin to eliminate the irrational fears which surround mushrooms and replace them with knowledge and a healthy respect. My suggestion for those who want to forage and have no actual hunting experience would be to forgo eating any mushroom until you find a fungi knowledgeable local or the local mycological society to hunt with. That's a great way to get comfortable with your local edibles make friends and be safe.
Have a Mushroom you want help identifying? - leave a message on the Steemit Mycology discord channel.
https://discord.gg/JJgEW2y
For The Online Mycokey program look Here
For A Crash Course On How To Identify A Mushroom Read The Amatuer Mycologist #3
For a Glossary Of Relevant Mycological Terms, Micheal Kuo's Website Provides
Information Sources:
http://www.mushroomexpert.com/boletus_edulis.html
https://en.wikipedia.org/wiki/Boletus_edulis
http://www.mykoweb.com/CAF/species/Boletus_edulis.html
https://en.wikipedia.org/wiki/Rubroboletus_satanas
https://en.wikipedia.org/wiki/Tylopilus_felleus
http://boletales.com/genera/boletus/b-edulis/
Photo Sources:
1
[2](By Dezidor, Own Work, CC BY 3.0 (http://creativecommons.org/licenses/by/3.0), via Wikimedia Commons)
[3](By Ron Pastorino, Mushroom Observer, CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0), via Wikimedia Commons)
[4](By Alinja Own work GFD via Wikimedia Commons)
[5](By Alinja (Own work) GFDL
[6](By photo taken by Archenzo in an Italian wood Piacenza's Appennino Own work GFDL, vie Wikicommons)
[7](By Tylopilus_felleus_060914c.jpg: bernd gliwa derivative work: Ak ccmCC BY-SA 2.5, via Wikimedia Commons)
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