Does washing mushrooms really ruin them?

Pick up a container of mushrooms and you'll likely see some dirt present. Of course you're going to want to wash them, but you might have heard that washing mushrooms ruins them, which you definitely do not want to do. Is water really the enemy of the mushroom?

According to Cook's Illustrated, some advise against washing mushrooms at all because there's a fear they'll soak up additional moisture which will turn them into a flavorless, waterlogged mess. Instead, many experts recommend brushing off the dirt instead. However, the folks at Cook's Illustrated note that mushrooms are already 80 percent water, and this led them to test out the fungi's ability to soak up any more moisture. They rinsed off a 6-ounce batch of whole mushrooms in cold water, weighing them before and after. They found that they gained a quarter ounce of water, and most of this wound up beaded on the mushroom's surfaces.

Those were whole mushrooms, though. Mushrooms that are already sliced should not be rinsed off because they will soak up water.

So, rinsing mushrooms is A-OK, but you can't just wash them off and put them back in the fridge and forget about them for a few hours even when they're whole. They will turn slimy and it will be disgusting, and nobody will want to eat them.

A good method for washing mushrooms involves using a salad spinner. Of course, you'll want to wash them off before slicing them up, but to do so, all you have to do is place the whole mushrooms in a spinner basket and rinse them off until all the dirt is gone. Then, put the basket into the salad spinner and spin them until they are dry. Blot off any excess moisture and you're good to slice, cook, and serve. 

If you don't have a salad spinner handy, use the same method with a colander and then remove as much water from their surfaces as you can with paper towels.

There are a few rules to keep in mind when prepping mushrooms: If you're serving your mushrooms raw, don't rinse with water — instead, use a brush (like a dry toothbrush) to remove dirt — or risk them being discolored. Cook your rinsed-off mushrooms immediately after cleaning them, definitely do not put them back in the fridge, and never rinse off already-sliced mushrooms. If you follow these rules, you'll have gorgeous mushrooms without dirt and that are not gross, slimy, or flavorless.