False Morels: Gyromitra, Carcinogens, and Controversy

With spring breathing life into the air it is time to start looking for morel mushrooms (Morchella species), and while it’s still a little early here in the Ottawa Valley, there is a mushroom popping up that has often has a lot of controversy around it.  This mushroom sometimes is called a beefsteak morel, or as I prefer, false morel.  This guy definitely resembles a beefsteak, and superficially a morel.  The Latin name for the species that most often grows here is Gyromitra esculenta, and despite its meaning delicious gyromitra, I would not eat this mushroom, despite frequent testimony that they are edible. 

Above: Gyromitra esculenta.
Below: the cap is attached to the stem in true morel species.

All gyromitra mushroom species contain gyromitrin, and while consuming small quantities of gyromitrin may not be immediately toxic, it is processed by the body into monomethylhydrazine (a component of rocket fuel), which is known to be carcinogenic and will build up in your body over time eventually causing fatal liver toxicity and complete organ failure.  Any given person’s tolerance or susceptibility is extremely variable; there are accounts of people suffering effects of toxicity after one large dosage, whereas others won’t encounter the same effects for years -- often taking smaller amounts over time until *BANG*  body shuts down and your adventures in eating wild mushrooms are over.

Above: the solid stem gives away a false morel.
Below: a hollow stem means a true morel.

One argument often made by those who pronounce this mushroom edible is that you can actually remove the gyromitrin by par boiling the mushroom in several fresh changes of water.  I will admit that this will work in theory, gyromitrin is a water soluble compound and could be boiled out... into the air you happen to be breathing.  Even after all that there is no promise that you have managed to leach it all out. A small quantity of gyromitrin almost always remains -- something I wouldn’t risk.
If you snoop around the internet you will likely find the debate ongoing between those who say it’s edible, and those who say it’s poisonous. You certainly will find a lot of information regarding gyromitrin as a chemical.  I have to claim a spot in neither camp. I would say that I COULD eat this and MAYBE prepare it in a fashion that’s SOMEWHAT safe, however, being rather fond of living a full and healthy life, I would need to be in some pretty dire straits before actually consuming it.  There are so many other edible wild mushrooms out there that don’t require you to play Russian roulette, it’s not worth risking.
All of that being said, it is a beautiful, interesting, and kind of creepy looking dude who plays an important role in the eco-system... but not in my diet. For more information on the edibility of this mushroom check out chef Alan Bergo's article: "On Cooking False Morels or Gyromitra Mushrooms". For more info on how to identify morel mushrooms properly check out this handy Morel Mushroom Identification Guide.
See you in the woods,


1 comment

  • Not all Gyromitra contain Gyromitrin only a few varieties have been found with it as well as a few varieties of Helvella. There has yet to be confirmation of gyromitrin in Gyromitra caroliniana as well as Gyromitra montana, Gyromitra korfii, Gyromitra brunnea with all of these being considered fine to eat and not toxic.


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