I’ve never cooked a mushroom before in my goddamn life. As a child, like most other children, I had two sworn enemies: mushrooms and onions. I’ve since learned to delight in the taste of onions and the flavor they add, but mushrooms are still iffy territory for me. I just don’t like the texture, you know? I guess I’ll just never be sophisticated.
Anyway, I still think mushrooms are really cool. They’re definitely smarter than us. That’s a problem for a different time, but did you know that the majority of mushrooms sold in grocery stores are actually grown indoors in a bed of moss? Awh! Mushrooms might look ugly and dirty (who doesn’t?), but they’re actually just ugly. What appears to be “dirt” on the mushrooms is likely just the natural coloration.
With that in mind — and the fact that mushrooms are so porous and sponge-like — rinsing them under water isn’t an excellent idea. It’s not going to harm you or the mushrooms per se, but it will likely make them rather mushy. Maybe that’s why I don’t like mushrooms — everyone’s been trying to feed me freaking water-logged mushrooms!
Instead, Bon Appetit recommends largely skipping the cleaning process with mushrooms. In the event you actually do find some moss or dirt on your mushrooms, you should wipe them off with a dry paper towel. If they really do seem truly dirty and you feel as though you absolutely must rinse them, you ought to dry them off afterward and cook immediately.
As for pesticides and the other invisible nasties you might want gone from your produce, mushrooms are usually relatively safe in this regard. According to the Environmental Working Group, which tracks pesticide use in fruits and vegetables in the U.S., mushrooms are among the “Clean Fifteen” items with the lowest amount of pesticide residue.
Despite all this, the FDA still states that you should wash all produce under running water before eating. It’s really a matter of your personal values: Do you want to play it safe and eat shitty tasting mushrooms, or do you want to live fast, die young and eat unwashed shrooms that taste as the gods intended?