And so, while every cook we see on TV tells us to wipe each mushroom with a damp cloth and never, ever rinse for fear those porous mushrooms will just soak up water and turn to mush, we've been happily giving ours a quick run under the faucet. It's far less time-consuming and, frankly, they taste just fine.
Well, we now have Gourmet magazine on our side...One of the little tips in the front of the July issue mentions that it's a myth that mushrooms can't be washed. In fact, Gourmet performed an experiment, soaking a bunch and testing how much water they absorbed. It was about one sixteenth of a teaspoon per mushroom — only a bit more than is absorbed by an asparagus, they say.
And that's if they soak in water. Ours merely shower.