Freezing mushrooms is a great storage technique. Since fresh mushrooms only last up to a week in the refrigerator, freezing lets you save them for a much longer period of time.
Edible mushrooms should be cooked before being frozen or they'll become mushy when reheated. A few extra minutes of cooking may save you a soggy mushroom in the end.
Always add frozen mushrooms directly to a dish without thawing. Three different cooking methods to use before freezing mushrooms are sautéing, blanching, and steaming.
This involves cooking pieces of mushrooms quickly at a high heat with a little fat. Since you will be freezing the mushrooms after they cool, you don't have to be quite as exact with ingredient amounts as you would with a traditional mushroom sauté.
To use, simply remove the desired amount and add to any mushroom recipe. With this method they'll maintain a more firm texture than with blanching or steaming.
The downside is that due to the fats involved, sautéed mushrooms won't last as long in the freezer. Try to use them within 9 months for the best quality. Check for freezer burn before using.
Blanching, or parboiling, is the process of cooking something in boiling water for a timed period, then plunging it into cold water to stop it from cooking further. This stops enzymatic actions that degrade the color, flavor, and texture of the mushrooms. It also can kill bacteria and remove dirt.
Freezing mushrooms after blanching works best for mushroom soup recipes. To use, add the frozen mushrooms to the soup 20 minutes before it's done.
Blanched mushrooms will keep in the freezer for up to a year.
Steaming is the process of cooking something in steam instead of a liquid. Steamed mushrooms hold their flavor and texture better than blanched mushrooms.
Mushrooms are often given an anti-darkening treatment before steaming to retain their color. To do this, cover them in water with a tsp of lemon juice added for every pint of water. Stir and let the mixture sit for 5 minutes.
Freezing mushrooms after steaming works for most mushroom recipes. To use, add the frozen pieces to any dish. You may add these to a stir-fry, but take care not to add too many at once and bring the temperature of the pan down.
Steamed mushrooms will keep in the freezer for up to a year.
Finally, always use proper packaging when freezing cooked mushrooms. Whether plastic containers, jars, or freezer bags, they should be air-tight and not crack at low temperatures.