For commercial mushrooms that I buy plastic-wrapped at the grocery store, I keep them in their original packaging in the refrigerator. Unopened, these mushrooms will keep for nearly a week before starting to go slimy and brown. If I open a package but have mushrooms leftover, I wrap the container in plastic wrap and poke a few holes to allow air flow.
Wild mushrooms get slightly different treatment. I've found that these keep better in a paper bag in the refrigerator's crisper drawer. The paper allows for better airflow while the crisper drawer keeps the air slightly humid and prevents the mushrooms from drying out. They'll start to get a little shriveled by the end of the week, but are still good for cooking.
Do you use these methods for storing mushrooms or have you found another method that works for you?
(Image: Emma Christensen)