Freezing Mushrooms: A Step-By-Step Guide

Mushrooms are a versatile ingredient, adding a savoury flavour and meaty texture to many dishes. They can be frozen raw or cooked, but their high water content means they can become soggy or mushy when defrosted. To avoid this, it's best to cook them slightly before freezing, by steaming or sautéing. This draws out the internal moisture, ensuring a nicer texture and more intact mushroom for use post-freeze. To freeze, transfer the mushrooms to a freezer-safe container or bag, removing as much air as possible to prevent freezer burn, and seal. Frozen mushrooms should be used within a year, but sooner is better, and they can be added directly to dishes like stews, casseroles, pasta bakes, stir-fries, and soups.

Preparing mushrooms for freezing

At this point, you have a choice to either steam blanch or sauté the mushrooms before freezing. This step is optional, but it will help to preserve the flavour and texture of the mushrooms. If you decide to steam blanch, dip the mushrooms in a solution of lemon juice or citric acid and water for 5 minutes, then steam for 3-5 minutes, depending on the size. If you prefer to sauté, heat butter and oil in a skillet over medium-high heat, add the mushrooms in a single layer, and cook without stirring for 4-5 minutes. Then stir and cook for an additional 3-4 minutes. Allow the mushrooms to cool completely before the next step.

Once your mushrooms are prepared, it's time to freeze them. Place them on a parchment-lined baking tray, ensuring they are spread out and not clumped together. Put the tray in the freezer until the mushrooms are frozen, then transfer them to a freezer bag. It is important to remove as much air as possible from the bag before sealing it. Label the bag with the date, and your mushrooms will stay good for up to a year, although the flavour and texture may start to diminish after four months.

Some varieties of mushrooms freeze better than others. Maitake mushrooms, for example, have a low water content and freeze well raw. However, due to their high water content, some types of mushrooms may become mushy when thawed, so it is recommended to use cooked or blanched mushrooms in dishes where you want to retain texture, such as casseroles or pizzas.

Cooking mushrooms before freezing

Mushrooms can be frozen raw, but their high water content means they can become soggy and mushy. Cooking them before freezing helps to preserve their texture, flavour, and nutritional value.

There are two main ways to cook mushrooms before freezing: sautéing and steaming. Sautéing involves heating the mushrooms in a frying pan with a small amount of butter or oil over high heat for about five minutes, or until they are fully cooked and most of the liquid has evaporated. It is important to note that sautéed mushrooms will have a shorter freezer life than steamed mushrooms.

Steaming is a quick cooking process that helps preserve produce before freezing. It works by destroying enzymes that can cause food to spoil. To steam blanch your mushrooms, bring a pot of water to a boil and place a steamer basket inside. Add the mushrooms and let them steam for 3-5 minutes. Then, immediately place them in ice water for the same amount of time that they were steamed.

Regardless of the cooking method, it is important to allow the mushrooms to cool completely before freezing. Spread them out on a tray and place them in the freezer until they are frozen solid. Then, transfer the mushrooms to a labelled, resealable freezer bag, removing as much air as possible before sealing. Frozen mushrooms will last in the freezer for 9-12 months and are best suited for cooked dishes such as soups, casseroles, stews, or pizza toppings.

Freezing cooked mushrooms

Cleaning and Preparing the Mushrooms

Start with fresh mushrooms that look and smell good. Avoid any with dark spots or a shrivelled appearance. You can clean the mushrooms by gently brushing off any visible dirt with a soft-bristled mushroom brush or a damp paper towel. Avoid soaking the mushrooms in water, as this can make them mushy. After cleaning, slice or chop the mushrooms according to your preferred size.

Cooking the Mushrooms

There are a few different methods you can use to cook the mushrooms before freezing:

• Sautéing: Heat butter and oil in a skillet over medium to high heat. Add the prepared mushrooms in a single layer and allow them to cook without stirring for 4-5 minutes. Then, stir and cook for an additional 3-4 minutes. Avoid adding salt during cooking, as it can draw out moisture and affect the browning process. You can add seasonings like salt, pepper, and onions after the mushrooms have browned, if desired.
• Steaming: Sort the mushrooms by size, as blanching times vary. If the mushrooms are larger than an inch across, slice or quarter them. To prevent discolouration during blanching, soak them for 5 minutes in a solution of lemon juice or citric acid and water. Place the mushrooms in a steamer basket over boiling water and steam for the appropriate time based on their size. Cool the mushrooms by plunging them into ice water for the same amount of time they were steamed.
• Roasting: You can also roast the mushrooms before freezing, although specific instructions for this method are not readily available.

Cooling and Freezing the Mushrooms

Allow the cooked mushrooms to cool completely. Spread them out on a baking sheet or tray and place them in the freezer to flash-freeze. Once they are frozen solid, transfer the mushrooms to a labelled resealable freezer bag or airtight container, removing as much air as possible to prevent freezer burn. Frozen cooked mushrooms can be stored for up to a year, although some sources suggest using them within 6 to 9 months for the best flavour.

Using Frozen Cooked Mushrooms

When ready to use, you can either thaw the mushrooms overnight in the refrigerator or add them frozen directly to a dish that will be thoroughly cooked. Frozen cooked mushrooms can be added to various recipes, such as quiche, stir-fries, pizza, pasta, sauces, and more.

Storing frozen mushrooms

To store mushrooms in the freezer, it is important to prepare them properly. They should be cleaned and dried before being frozen. Mushrooms can be frozen raw, but they will become very mushy when cooked, so it is usually best to cook them slightly before freezing. They can be sautéed or steamed before being frozen.

To sauté the mushrooms, heat a small amount of butter or oil in a frying pan over high heat. Add the mushrooms and cook for about five minutes, or until they are fully cooked and most of the liquid has evaporated. To steam the mushrooms, soak them in a solution of lemon juice or citric acid and water for five minutes, then place them in a steamer basket and steam for 3-5 minutes.

Once the mushrooms are cooked, they should be spread out on a baking sheet and placed in the freezer until they are frozen solid. Then, they can be transferred to a labelled, resealable freezer bag or container, removing as much air as possible before sealing to prevent freezer burn.

Frozen mushrooms can last for up to six months in the freezer and should be used in cooked dishes, as freezing changes their structure and texture, making them unpleasant to eat raw. They can be added directly to hot recipes, such as soups, casseroles, pasta dishes, and stir-fries, or thawed overnight in the fridge before use.

It is important to note that mushrooms are like sponges and will absorb scents, so they should be kept away from strong-smelling items in the freezer. Additionally, avoid stacking items on top of the mushrooms to prevent bruising.

Using frozen mushrooms

Frozen mushrooms can be used in a variety of dishes, from soups and sauces to pizzas and burgers. They can be added directly to recipes that will be heated, or thawed in the refrigerator before use. Here are some tips for using frozen mushrooms:

• Frozen mushrooms are best suited for cooked dishes and should not be consumed raw. Cooking enhances their earthy flavour and improves their texture.
• If you're using frozen mushrooms in a dish that doesn't involve cooking, such as a salad or pizza topping, allow them to thaw in the refrigerator first. This will soften them and make them easier to work with.
• Frozen mushrooms are versatile and can be added to various dishes to boost both flavour and nutrition. They can be tossed into soups, stir-fries, casseroles, and pasta sauces without the need for pre-thawing or additional prep.
• To maintain the nutritional value of frozen mushrooms, avoid recooking them. Simply warm them up by adding them towards the end of your meal preparation. This ensures you get the most out of their antioxidants, B vitamins, copper, and potassium content.
• Frozen mushrooms can be used to make delicious marinated snacks. Sauté them with a sprinkle of salt, allow them to cool, and then store them in a sealed container in the refrigerator for up to a week.
• For blended dishes like burgers, it is recommended to use thawed and diced mushrooms. Mix them with ground meat for juicy, flavourful burgers.
• Frozen mushrooms are convenient and help reduce food waste. They can be purchased or prepared in advance, ensuring you always have a tasty and nutritious ingredient on hand.

Frequently asked questions