Should you wash mushrooms before cooking them?
Dear Straight Dope:
My sister and I were preparing lasagne the other night and I recalled advice I saw on a television show that said you're not supposed to wash fresh mushrooms before you use them in recipes. Is this true, and if so, why? Am I following sage advice or subjecting my family to a dangerous illness? We await your answer. Please hurry, the lasagne is getting cold.
Well, Karon, if you want answers of a culinary nature, you've come to the right place. According to two unimpeachable sources, Larousse Gastronimique (that's a culinary encyclopedia for you TV dinner heathens out there) and Owen Rice, proprieter of MycoLogical Natural Products Ltd. (purveyor of fresh and dried wild and gourmet mushrooms), it is among the deadliest of sins to scrub those fungi. The way Larousse puts it, one suspects you'd be laughed right out of Cordon Bleu for even thinking of it.
"In order to retain the full flavour of mushrooms, it is best not to peel or wash them, but simply to wipe them with a damp cloth and then dry them. If the stalks are tough, stringy, or maggoty, they are removed. Otherwise, the base of the stalk is sliced off. Only the mushrooms that become sticky in damp weather (including certain boletus mushrooms) and those with a bitter outer skin (cortinae and pholiotae) are peeled. THe fleshy tubes of boletus mushrooms are removed if they are too spongy, and the gills of certain other mushrooms are trimmed if they are too ripe. If absolutely necessary, the mushrooms may be washed very quickly, but never allowed to soak. Varieties such as morels, which have a cap that is pitted like a honeycomb, are cleaned with a small brush."
There you go; spoken like a true food snob. Owen, on the other hand, is a bit more pragmatic. "The main line of reasoning here is that mushrooms are very absorbent and some varieties can soak up a lot of water." Cooking soggy mushrooms affects the texture; sauteed mushrooms, for example, will get soupy rather than brown and firm to the bite. He goes on to say that this is not always the case. Different mushrooms have different textures and different people have different preferences for dealing with them. There are people out there who soak wild mushrooms in salt water to get the worms out that sometimes infest them. Mmm-mm. Owen's preference is to not wash mushrooms at all, or to brush them with a soft brush if you really must. Wild mushrooms, of course, come garnished with the humus from the forest floor or from whatever dead wood they grow on. Commercial mushrooms on the other hand ... let's just say that I personally give them a rinse.