The Ultimate Guide To Storing Mushrooms, By Microbiologists

Mushrooms are a versatile ingredient used in cooking, but they are highly perishable and delicate. To extend their shelf life, it is crucial to store them correctly. While the refrigerator is the ideal place to store mushrooms, the crisper drawer is often too moist. Instead, the main section of the refrigerator is recommended. This helps slow down decay and extends the shelf life of mushrooms. To prevent moisture buildup, it is best to avoid plastic containers and bags, opting instead for breathable packaging like cardboard boxes or brown paper bags. Additionally, keeping mushrooms unwashed and whole further prolongs their freshness. For longer storage, cooking and then freezing mushrooms is an option, although this may alter their texture and flavour.

Avoid plastic containers

When storing mushrooms, it is best to avoid plastic containers. Mushrooms have a high moisture content of around 90%, and their structure is such that they can easily lose water. If trapped in a plastic container or bag, the mushrooms will end up sitting in a damp container, which causes discolouration, mould, and slime. Plastic wrap with no holes can also trap moisture and speed up spoilage.

Instead, it is recommended to store mushrooms in a breathable container, such as a paper bag, which can help to absorb any excess moisture. Paper bags can be layered with paper towels to further help with moisture absorption. Cloth bags are another option for mushroom storage, as they allow for moderate airflow, preventing too much moisture loss while avoiding condensation.

If you wish to store mushrooms for longer, you can dry them or cook and freeze them. To dry mushrooms, use a dehydrator or air-drying techniques, and then store them in an airtight glass jar. Freezing mushrooms involves cooking them first and then placing them in a freezer-safe bag.

Use breathable paper bags

Properly storing mushrooms is crucial to prevent mushroom poisoning, which is often caused by improper storage. Mushrooms need to breathe to remain viable for human consumption. Therefore, they should be stored in breathable paper bags.

Paper bags are ideal for storing mushrooms because they offer the right balance of air circulation and moisture absorption. They allow mushrooms to breathe and slowly dry out, preventing the rapid growth of bacteria. Plastic bags, on the other hand, trap moisture, leading to a damp environment that degrades the quality of the mushrooms and causes discoloration, mold, and slime.

To store mushrooms in a paper bag, place the mushrooms in a small paper bag and fold the top down to close it securely. Do not seal the bag, as this will restrict airflow. Instead, loosely fold the top to allow for proper air circulation. You can line the bag with a paper or cloth towel to absorb any moisture released by the mushrooms and control condensation.

Store the paper bag containing the mushrooms in the refrigerator. The cool temperature will maintain their crispness and extend their shelf life. Mushrooms stored in paper bags can last up to 10 days, depending on the species and their condition. However, it is best to use them within a week for peak freshness and flavour.

Control condensation

Mushrooms are best stored in a place with moderate airflow to prevent too much moisture loss while avoiding condensation. They are often sold in plastic containers, but this is not ideal for storage as plastic traps moisture, causing the mushrooms to sit in a damp container or bag, which leads to discolouration, mould, and slime.

To control condensation, line a breathable paper bag with a paper or cloth towel to absorb any moisture released by the mushrooms. This method allows them to last up to 10 days. If you wish to store them for longer, dry them or cook and freeze them.

It is also important to note that mushrooms are best stored in the fridge, but not in the crisper, as many crispers are set to a high-humidity setting, which encourages the condensation of water on the mushrooms' surfaces.

Additionally, freshly harvested mushrooms can be left on the counter for about a day, but they should not be washed before storing as moisture is the number-one enemy when it comes to keeping mushrooms fresh.

Refrigerate

Refrigeration is a common method for storing mushrooms and prolonging their shelf life. Mushrooms have a high water content, and their structure allows them to easily lose water. Therefore, the key to storing mushrooms in the refrigerator is moisture control.

When storing mushrooms in the refrigerator, it is recommended to avoid using plastic containers or bags. Plastic traps moisture, causing the mushrooms to sit in a damp environment, which leads to discolouration, mould, and slime. Instead, opt for a breathable paper bag, such as the ones often used to package and sell mushrooms at farmers' markets. A mesh produce bag is also a suitable alternative. To further control condensation, line the bag with a paper or cloth towel to absorb any moisture released by the mushrooms. This storage method can keep mushrooms fresh for up to 10 days.

If you purchase pre-packaged mushrooms, you can simply place them in the refrigerator as the package's perforation will allow air to circulate and dry out excess moisture. When you're ready to use them, wipe off any dirt with a damp paper towel, rather than washing the mushrooms, as this can cause them to absorb too much water and spoil faster. If you don't use all the mushrooms at once, cover them back up with plastic wrap, but be sure to punch a couple of holes in the wrap to maintain ventilation.

For longer-term storage, you can dry or cook the mushrooms and then freeze them. Cooking methods such as blanching, sautéing, poaching, or steaming help lock in texture and flavour before freezing. To freeze raw mushrooms, it is recommended to first cook or blanch them to help preserve their structure and flavour. Then, freeze them on a parchment paper-lined baking sheet until they are frozen solid before transferring them to an airtight, vacuum-sealed plastic bag to prevent freezer burn.

Freeze

Freezing is a great way to store mushrooms and avoid food waste. It is best to freeze mushrooms at the peak of their freshness. Mushrooms that are dry, shrivelled, darkened, mouldy, or give off an unpleasant odour should not be frozen.

To freeze mushrooms raw, brush off any visible dirt, trim the stems, and place them in a freezer bag. Squeeze out as much air as possible and seal the bag before placing it in the freezer. Raw mushrooms can also be frozen after steaming or sautéing to preserve their nutritional value. To steam blanch, soak the mushrooms in a solution of one teaspoon of lemon juice or 1.5 teaspoons of citric acid to one pint of water for five minutes. Then, steam the mushrooms for 2-5 minutes, depending on their size, and immediately plunge them into ice water for the same amount of time. Drain the mushrooms, spread them out on a tray, and freeze until solid before transferring them to a labelled, resealable freezer bag. Sautéing is another option for preparing mushrooms before freezing. This involves cooking the mushrooms in 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. Allow the mushrooms to cool, then freeze them in a similar manner to the steamed mushrooms.

Frozen mushrooms are best used within a year, although they will last for up to 9-12 months. They are most suitable for cooked dishes such as soups, casseroles, stews, or as a pizza topping. Frozen mushrooms can also be added to dishes like pasta, rice, or quinoa. It is recommended to cook frozen mushrooms from frozen, as they can become soggy if defrosted.

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