EATING RAW MUSHROOMS CAUSES PROBLEMS Jan Lindgren
MushRumors, Oregon Myco. Soc., March?April 1997

Most of us think nothing of eating a few sliced, raw, ?store bought? mushrooms in salads, on hors d?oeuvre trays, or when preparing them for the frying pan. Usually the amount eaten is so small that we don?t notice any unpleasant symptoms, but it is not a good idea to eat any mushroom raw. I know the commercial growers will laugh and scoff at this statement and some of you will say you can eat lots of them with no problem, but researchers have shown that even Agaricus bisporus, the ?store bought? mushroom, contains agaritine which metabolizes into a hydrazine.

Many hydrazines are known to be strong carcinogens and can be found in a lot of edible mushrooms. Cooking destroys some or all of the hydrazines, but the steam given off during cooking has been known to make some cooks ill. Besides this fact, the structural material or cell walls in mushrooms is made of chitin, and humans don?t have the ability to digest this derivative of cellulose. The body can do several things to this undigested chitin. It can expel it by vomiting or send it the other way with diarrhea. Small amounts may pass through the gut with other food and go unnoticed, or it may stay in the gut where bacteria will work on it causing bloating, gas, and other discomfort. Cooking does not destroy chitin but may ease its effect. Once in the habit of eating A. bisporus raw, people think they can eat any mushroom without thorough cooking, and this is where they may experience some very unpleasant symptoms. In February, a case recorded at the Or! egon Poison Center told of a woman who ate home cultivated, raw Pleurotus ostreatus with her lunch and experienced nausea, vomiting, and diarrhea. While this may not be a serious health problem it could have been avoided. A better job of educating people about wild collected and cultivated mushrooms is necessary.

We assume that chefs at good hotels and restaurants know not to serve raw mushrooms, but this isn?t the case. You may recall that on June 8, 1991, about 70 people were made ill at a large banquet in Vancouver, B.C., because they were served raw morels and other raw mushrooms in a salad.

The spring verpas, morels, and brainlike mushrooms (Gyromitra) are notorious for their toxicity in the raw state and, for some people, in the cooked state. Please be careful and remember that drying is not a substitute for cooking and that folding sliced mushrooms into an omelet just before serving or pouring hot vinegar and spices over raw mushrooms is not efficient heating or cooking. The best rule to follow is cook all mushrooms thoroughly before eating and eat them in moderation.

A good reference for more information about mushrooms and health is Mushrooms: Poisons and Panaceas by Denis R. Benjamin of Seattle.

The kicker with Agaricus species, including the buttons, is that one of their primary hydrazine components, along with gyromitrin, is “agaritine,” a substance somewhat resistant to cooking heat, with a significant percentage (25–75%) of agaratine material typically remaining after being subjected to various methods of cooking. So, the question as far as avoiding hydrazines in Agaricus is concerned, actually becomes whether to eat members of this genus at all.

We need to keep in mind that lab tests and subsequent conclusions drawn concerning carcinogenic or mutagenic health hazards of hydrazine involve massive doses of isolated extracts administered to mice in a concentrated time frame. Similarly disturbing test results are likely to be found with many substances present in many, many foods humans commonly eat without suffering or even worrying about any particular health concern. The relatively unblemished human history of consuming edible Agaricus species suggests we may continue to do so. The science may suggest we should not over indulge, but we already knew that. As I know of no one stricken by cancer or any other malady as particular result of eating Agaricus, and since the genus includes some of the most delectable of all edibles, there are several wild Agaricus species that remain firmly ensconced on my preferred edibles list.

jarekjurek pisze:

Słyszałem od znajomych grzybozjadaczy z większym stażem, że po zrobieniu takiego naparu, nawet nie trzeba zjadać łysic i wystarczy wypić samą wodę. Ale nie sprawdzałem, zawsze konsumowałem i grzyby i zaparzoną zupo-herbatkę. I zawsze działało tak jak powinno.