If you've stocked up on fresh mushrooms, you'll need to find a way to preserve them.They may only keep a week or so in the fridge, but that can change if you get your freezer involved.You'll just need to take some pre-freezing steps to ensure they don't become mushy when thawed.Either use a paper towel to brush any visible dirt off the mushrooms or lightly rinse them in cold water.Don't soak the mushrooms, and pat them very dry when you finish.Getting the mushrooms too wet is what can cause them to become mushy when thawed.Then, simply line them on parchment paper and freeze for at least two hours.If frozen correctly, your raw mushrooms can last up to a year in the freezer