Is it safe to reheat mushrooms?

Question

According to this very popular Bright Side video (https://youtu.be/P2BVyHOdFUo) , it is not safe to reheat mushrooms as they not only lose their nutritional value, but can also make you ill. This, clearly, is a very simplistic position as we would not have such delicacies as tinned mushroom soup, and pre-cooked mushrooms on pizza toppings etc.

So what precautions should one take when reheating mushrooms? Is it a particular variety that is prone to this? I have been cooking and reheating fresh white and brown mushrooms in dishes for many years now in stews and casseroles without any ill effects. Have I just been lucky?

Answer 1

That's a myth, and as such your follow-up questions are moot.

There is no scientific evidence of any kind that any particular method of reheating mushrooms -- or not reheating them -- is dangerous or problematic in any way. The popularity of that video does not automatically make it valid; videos about "slenderman" are equally, if not more, popular.

What's problematic about leftover mushrooms has nothing to do with reheating them, but rather with storage. Mushrooms, like garlic, potatoes, and onions, are dug out of the dirt and as such carry an array of dirt-loving bacteria. If the mushrooms aren't properly washed in the first place (and many people think you can't wash mushrooms because of another myth), and then they are not refrigerated promptly and correctly, they become incubators for those bacteria, including the dreaded Clostridium botulinum.

However, if your mushrooms are contaminated, those bacteria and their toxins are present whether you microwave your leftover stroganoff or eat it cold.

The idea that the microwave destroys the nutritional value of the mushrooms is just the old hoax, promulgated when home microwaves were introduced in the 70's, and equally nonsense.