Over on the Mushroom Identification Forum on Facebook, there is a lengthy and vehement flame war going on today about the safety and desirability of eating raw mushrooms. It is astonishing to read about the variety of species that some people will consume in the uncooked state, and I question the wisdom of many of their choices. The argument now seems to be generating more heat than light.
Instead, read this article. It seems to be the definitive reference I’ve found about whether or not to cook your edibles:
- Cooking lessens the likelihood of bacterial or nematodal infection.
- The chitin in fungal cell walls is hard to digest, and this can induce vomiting and other GI symptoms in many people. Cooking over heat alleviates this by breaking down the chitin, which may also release more absorbable nutrients from the cells.
- There are many other irritating, poisonous, or carcinogenic compounds in fungi (notably in true and false morels, but even in grocery store button mushrooms) that can be successfully cooked out of them to varying degrees.
- However, and most Importantly, there are some toxins such as the amanitins in death caps and the orellanines in Cortinarius that cannot be effectively cooked out of the mushroom.
- Among the well-known choice edible species, the consumption of raw morels, hedgehogs, chanterelles, or oyster mushrooms is highly capable of making you sick. [In fact, according to a recent annual toxicology report from the North American Mycological Society, true morels (Morchella) are responsible for more cases of reported mushroom toxicity than any other genus, and in most of these cases this is because they were consumed raw.] Porcini are less commonly irritating and more commonly eaten raw, but some people are sensitive to them even in the cooked state. Use caution.
- Edible Amanitas such as the coccora (Amanita lanei) and the Caesar’s amanita (A. caesarea/”cochiseana”) shown above are commonly eaten raw with no noticeable consequences. If you like these, you should consider doing as the Italians do, and use a lemon or lime juice marinade so as to make a “ceviche”. This will have a strong anti-bacterial effect.
- Brining and pickling, common in Eastern Europe, also inhibit bacteria and mold. Russians will indiscriminately boil and pickle any Russula they gather, even the known emetic types, and seem not to suffer by eating them after this preparation.
- Edible gelatinous oddballs such as witch’s butter (Dacrymyces/Tremella) or toothed jelly fungi such as Pseudohydnum gelatinosum are typically eaten raw, but so rarely and in such small quantities as to be insignificant in the reports of gastric upset.
- The fly agaric (Amanita muscaria) is sometimes boiled to remove its toxins and eaten. This blog has addressed this practice and its pros and cons several times over the past year.
Personally I am not a fan of any raw mushrooms. Even the grocery store button mushroom, Agaricus bisporus, tastes lousy when raw. How did it become fashionable to put them on salads, especially when so many people suffer gastric distress afterwards?
Porcini and Caesar’s amanitas are probably the two wild types that are most commonly recommended for raw consumption. I’ve tried both and… meh. Cooked is better. I put the Caesar’s in Asian stir-fry dishes with great success. I think some of the raw-food fad that sees dishes served with raw porcini shavings is just a testament to the chef’s ego. I don’t buy into it.
As the MykoWeb article notes, there is also a possibility of bacterial or nematodal (worm) infection when eating raw mushrooms. Washing them should be mandatory, but the risk is even more effectively eliminated with cooking. If you need persuading on this point, look at Laurie Herring’s photo of a Leccinum surrounded by elk droppings:
One last thing I would note is that this article addresses only the intrinsic toxicity of the various mushroom species. It does not deal with mushroom allergies, which affect only a small percentage of individuals. These vary by species, and can even result from ingestion of the commonplace white button mushroom sold in groceries.
What do you think? Do you eat and enjoy raw mushrooms? Ever suffer a tummy ache because of it? Let us know in the comments.