One of the reasons that growing your own mushrooms at home is so rewarding is that they are so much fresher than what you can get at the supermarket or even a farmers market. But sometimes you can't eat all of your freshly harvested mushrooms right away (especially when you grow a huge crop of them). Here are some of our favorite ways to store them.
In the Fridge
If you just need to store them for a few days, the refrigerator is your best bet. Just put your cluster of mushrooms in a paper bag, fold the bag closed, and pop them in the fridge. This allows the mushrooms to breathe a bit, and it prevents them from drying out. Alternatively, you can put them in a plastic or glass storage container, but we like to put a paper towel at the bottom of it to prevent condensation from sitting against the mushrooms. That's what you want to avoid; moisture can make the mushrooms soft and mushy. Properly stored, a cluster of oyster mushrooms should stay fresh in the refrigerator for about 5 days.
In the Freezer
If you have a really big bunch of mushrooms or need to store them for a longer period of time, you can try freezing them. Mushrooms do tend to lose a bit of their texture when you freeze them, but they should still work great in stews, sauces, and soups. Mushrooms freeze best after you sauté or blanche them. Just cook them, cool them, and then freeze them. If you want to freeze raw oyster mushrooms, we recommend separating the cluster into individual caps first. Whether pre-cooked or raw, spread your mushrooms out on a sheet pan, and then freeze them. This way, they won't clump together in one big piece when they freeze. After they are frozen, you can transfer them to a freezer bag or storage container for longer storage.
Dry Them
Drying mushrooms allows you to concentrate a lot of their umami flavor and nutrition and store them for a longer period of time at room temperature. This works best in a dehydrator because the lower temperature helps preserve more of the mushrooms' flavor, but you can also use your oven. Set your dehydrator to 110 degrees F and arrange individual oyster mushrooms caps in a single layer without them touching. Dehydrating should take about 4–6 hours, but it largely depends on the size of the caps and your dehydrator. If you want to use your oven, arrange dry oyster mushroom caps on a sheet pan and put them into a 150-degree F oven for an hour. Flip the mushroom caps over and bake for another hour. Take them out of the oven, and let them cool. After they cool, check if they're completely dry. If not, return to the oven and let them dry for another 20–30 minutes. Cool, test, and repeat if necessary until they are completely dried out. Store your dried mushrooms in an airtight container in a cool, dark cupboard.
To rehydrate dried mushrooms, place them in a heat-proof bowl and pour boiling water over them. Let them soak for about 15–30 minutes. Drain the mushrooms, and reserve the flavorful soaking liquid to add flavor to soups and sauces. Use the rehydrated mushrooms as you would use fresh ones, perhaps in this (pulled oyster mushroom bao recipe).
Tip: You can also grind up dry mushrooms and use as healthy, and umami-rich flavoring for dishes like chili.