Botulism in mushrooms

ботулизм фото
botulism molecules

Most of us with the word botulism have an association with canned food. First of all it refers to the mushroom blanks of home origin.

Why is botulism in mushrooms and how to destroy a dangerous bacterium? Where does it come from in canned food and how to make twists in order to avoid dangerous poisoning? Let's figure it out.

A bit of history

Botulism and fungi are far from the only combination. Traditionally, from the middle of the 20th century, when they began to massively use hermetic canning, and to this day the source of the disease for most of the victims are home preparations for the winter. But in historical times, mass cases of botulism in Russia arose only as a result of eating salted and dried fish. In Europe, poisoning was associated with meat sausages, hence the name of the disease (Latin botulus - sausage).

ботулизм в грибах фото

Botulism is a dangerous toxic and infectious disease caused by toxins of the bacterium Clostridium botulinum. This wand lives in the soil and is common everywhere. It is capable of forming spores that are extremely resistant to adverse environmental factors - high temperature (up to + 120 ° C), lack of moisture, ultraviolet radiation and disinfectants. In anoxic conditions and at temperatures above +10 ° C, the bacterium actively multiplies with the release of large amounts of gases. A byproduct of the vital activity of the bacillus is the botulinum toxin, which has a paralyzing effect on the nervous system and the muscles of animals and humans.

For fatal poisoning, a microscopic dose of botulinum is enough - from 5 to 50 ng / kg body weight. Without timely medical intervention, fatal outcome is likely in 30–60% of cases, and even with treatment, this figure approaches 10%. That is why botulism is one of the most dangerous foodborne diseases and its prevention among food poisoning takes the first place among other diseases.

Where does botulism in mushrooms come from

ботулизм в грибах как выглядит According to statistics, more than half of cases of poisoning are associated with the consumption of canned homemade mushrooms. According to other sources, in Moscow and the region this figure reaches 84%. Fish accounts for 10%, canned meat and sausages - about 4%. Why does mushroom poisoning cause botulism more often than others? Since the bacteria are contained in the soil, it is very difficult to get rid of them when preparing them - mushrooms are the most contaminated with soil compared to other products, and you will not be able to completely remove its microscopic particles.

As for industrial canned food, the danger of botulism in mushrooms and other products is minimized, because the plants use special high-temperature regimes for sterilizing products.

How does botulism develop in mushrooms? To accumulate toxin, certain conditions are necessary. The pathogen sticks fall into the mushrooms along with the ground. The reproduction of bacteria occurs in closed jars without oxygen. The optimal temperature for botulinum is +35 ° C, so when storing blanks at room temperature, the risk of poisoning increases. Home temperature sterilization regimes have practically no effect on the pathogen spores, especially since they cannot affect the already produced toxin. Nevertheless, the observance of a certain technology of mushroom spinning reduces the risk of botulism to a minimum. We will talk about this a little lower, and now we will learn how to properly store mushrooms in order to avoid poisoning.

How to avoid botulism in canning mushrooms

Since only those products that for some time were stored under a tightly closed lid without oxygen, become dangerous to health, you can only be poisoned with canned food. For example, botulism in fried mushrooms is found in the case when the original product was initially preserved, and then opened and cooked.

To minimize the trouble with mushrooms, follow the following rules for storage and preparation of the product.

  1. как избежать ботулизма при консервировании грибов Keep canned food in a cool cellar room, refrigerator, at a temperature not exceeding +6 ° C.
  2. Do not store homework for more than one year.
  3. Before eating, pickled mushrooms must be further processed - boil, bake or fry.
  4. Recycle collected mushrooms immediately - do not leave them for tomorrow.
  5. When harvesting, carefully cut the mushroom, leaving the roots in the soil, so as not to soil the entire contents of the basket.
  6. Wash and clean the raw materials thoroughly from soil and debris.

How to preserve

The only sure way to avoid botulism in mushrooms is to harvest them in such a way that they do not require airtight closures. It can be salted in an open way or dried. Proven antiquated methods will keep the product no worse than the new-fashioned marinade.

What to do if these recipes do not interest you? Here are some tips on how to avoid botulism when preserving mushrooms, which will minimize the risk.

  1. как избежать ботулизма в грибах Do not seal canned mushroom metal lids. Unfortunately, most housewives do not comply with this rule. Meanwhile, the banks should be closed with parchment paper or thick capron lids.
  2. Recipes in which mushrooms are poured with hot marinade without boiling are very dangerous. In this case, canned food should stand in the refrigerator for at least 10 days and should be eaten as early as possible.
  3. To reduce the likelihood of botulism in pickled mushrooms, boil them for 30 minutes before canning.
  4. Remember that boiling does not guarantee the destruction of botulism bacteria, since spores easily withstand temperatures of up to +120 ° C. Therefore, it is possible to sterilize canned food with the help of an autoclave, in which temperature is possible above +125 ° C.

A simple and reliable way to preserve mushrooms for a long time is freezing. With the advent of freezers available, this method is becoming increasingly popular.

Signs of botulism in canned mushrooms

признаки ботулизма фото
cap swelling

How to identify botulism in pickled mushrooms? The main danger is that externally the product can look quite harmless. Mushrooms taste good, do not change color and smell, however, microscopic amounts of toxin can already be inside the jar. Moreover, if a product is eaten by several people, it is likely that not everyone will get sick, but one or two of them who have caught the toxin.

Still, there is unequivocal evidence of the presence of the botulinum bacteria in a sealed jar. Here are the characteristic signs of botulism in canned mushrooms:

  • Bomb's can - swelling of the lid;
  • clouding of the content.


The toxin is very stable and can persist in canned food for years, even if the bacteria have long died. It is not affected by salt, sugar, vinegar and spices. Therefore, there is no way how to kill botulism in mushrooms.

All suspicious banks, as well as canned foods with a shelf life of more than one year should be thrown away without regret!

Repeat preventive measures to help avoid poisoning. It is necessary to strictly adhere to several rules for harvesting mushrooms for the winter.

  1. профилактика ботулизма In no case do not seal the marinade sealed with the help of tin lids - it is better to use nylon covers or parchment paper.
  2. Thoroughly clean the raw materials from debris and earth.
  3. Boil the mushrooms for half an hour before canning.
  4. Keep canned food in a cold place and store them for no more than a year.
  5. And to throw out suspicious cans with a swollen lid or clouded contents without regret.

Do not risk your health and do not try to try the product - as mentioned earlier, botulin may be present in canned foods that are apparently not spoiled.

In conclusion, we can say: it is always necessary to remember that any canned food can be a source of such a dangerous food infection as botulism. Mushrooms in this regard are the most dangerous, which is caused by the popularity of pickled mushroom canned food, where in anaerobic conditions, that is, without oxygen, ideal conditions are created for the growth of clostridia, especially at 35 ° C.