Can you freeze cooked mushrooms?

In this brief guide, we will answer the query, “Can you freeze cooked mushrooms?” and will discuss ways to freeze mushrooms.

Can you freeze cooked mushrooms?

Yes, you can freeze cooked mushrooms. Mushrooms may be prepared in a variety of ways, including roasting or simply sautéing in oil or butter. Make sure they’re in an airtight container and then freeze them thoroughly. Make a date and contents label, then put it in the freezer. As a leftover, it should be consumed within 4 days when stored in the refrigerator and for a maximum period of 4 months, when stored in the freezer, according to the USDA.

Effects of freezing mushrooms

Fresh mushrooms may be refrigerated for approximately a week before they start to lose their freshness and become squishy, brown, or slimy. Mushrooms may be frozen, but do so at your own risk as it can degrade their flavor.

While numerous factors are involved in quality loss in frozen mushrooms, the most detrimental is the enzymatic browning reaction. In some cases, blanching can be used prior to freezing to avoid browning of vegetables, however, studies have reported that in the case of mushrooms, blanching was harmful to the characteristic structure of mushrooms. The blanching process itself reduced the initial mushroom whiteness, and blanched frozen mushrooms showed a remarkable toughness after thawing and cooking. However, the omission of the blanching process resulted in a maintenance of the original structure characteristics but did not alter the enzyme activity in the mushroom tissue. Excellent results in stabilization of the color of frozen mushrooms by inhibiting undesired discoloration were obtained after washing fresh mushrooms in sodium metabisulfite solutions (1).

Frozen food loses part of its nutritional value over time. B vitamins, copper, potassium, and vitamin D are all abundant in mushrooms. Several water-soluble vitamins may be affected by freezing such as riboflavin, niacin, and folate, which are all water-soluble. Make sure to keep in mind that fresh food loses some of its nutritional value over time. There is a loss in the antioxidant properties of mushrooms due to freezing. Many antioxidant compounds are mainly present as a covalently bound form with insoluble polymers. Therefore, it is suggested that heat treatment might disrupt the cell wall and liberate antioxidant compounds from an insoluble portion of mushroom, which, in turn, increases the pool of bioaccessible antioxidant compounds (2).

In the same way, it is possible to alter the appearance of the texture. Although fresh mushrooms may be frozen, their high water content means that when they are thawed, they become mushy. Squishy mushrooms may be OK in certain soups, casseroles, and blended recipes, but they may not be ideal in others. Freezing mushrooms drastically affects their texture, especially when mushrooms are blanched. Hardness increases with blanching time, as well as with storage period. Studies showed that, as storage time of frozen mushrooms increased from 3 to 6 mo, shear press increased very significantly. Hardness of frozen-thawed mushrooms was confirmed through sensory evaluation (1).

Although various pre-freezing preparation procedures may preserve the freshness, texture, and nutrition of mushrooms, it is not always possible.

Ways of storing mushrooms in the freezer

When it comes to freezing mushrooms, the fresher they are, the longer they will last. Firm and earthy, the fresh texture and scent of mushrooms are irresistible. In addition, they’re devoid of mushy or dark areas.

You may be able to obtain locally produced mushrooms at your local grocery shop, but you may also find them at your local farmer’s market. Brush the dirt off the mushrooms before freezing them. Washing mushrooms before freezing them might cause them to become mushy when they’re cooked.

Trim the mushrooms’ stems and put them in a freezer-safe plastic bag if you want to freeze them uncooked. Before closing the bag and putting it in the freezer, squeeze out as much air as possible. Preparing mushrooms before freezing is suggested if you don’t want to freeze them uncooked.

Steam  Blanching

Preserving food before freezing is easier using steam blanching, a rapid cooking method. To prevent food from spoiling, it obliterates enzymes that speed up the process. The steam blanching process, which inactivates Listeria and Salmonella, two prevalent foodborne germs, improves the mushrooms’ safety before freezing them.

Blanching food also has the potential to retain nutrients. Before steaming, separate the mushrooms by size or chop them into similar-sized bits to reduce the amount of time they need to be blanched.

A study showed that after 14 d of storage, mushrooms washed in water would not be acceptable for the normal consumer due to strong browning. Washing in water caused an increase in storage browning of frozen mushrooms. Physical damage to the mushrooms during washing contributed to the rupture of the membranes separating the compartments of polyphenol oxidase (PPO) enzyme and phenolic substrates. The subsequent mixing of enzyme and substrates forms brown compounds and reduces whiteness. No significant change in whiteness of frozen mushrooms during 90 d of storage was detected when short-time dipping in boiling water was applied. In this matter, blanching is positive (1). 

However, blanching is undesirable because of weight loss and toughness increase during storage of blanched frozen mushrooms. A study demonstrated that blanching time before freezing had a significant effect on the texture of frozen mushrooms. Frozen whole mushrooms, blanched for 5 min, had markedly tougher texture than those blanched for 1 or 2 min (1). 

An alternative to prevent both hardening and browning is washing with sodium metabisulfite, which could effectively avoid the enzymatic browning caused by polyphenol oxidase. Mushrooms washed in water with sodium metabisulfite would be acceptable to the wholesalers even after 30 d of storage. Sulfur dioxide and its derivatives are the most powerful and extremely versatile PPO inhibitors, which inhibit enzymatic as well as nonenzymatic browning of vegetables, fruits, and mushrooms during their storage, freezing, and processing (1).

First, soak your fresh mushrooms in a combination of 2 cups (480 mL) of water and 1 teaspoon (5 ml) of lemon juice for 5–10 minutes to avoid discoloration during the blanching procedure. The mushrooms may be steamed using 4 cups (960 mL) of water and a teaspoon (5 mL) of lemon juice. Alternatively,

Bring a saucepan of water to a boil and set a steamer basket inside to blanch your mushrooms. Steam the mushrooms for 3–5 minutes after adding them to the basket.

To cool the mushrooms, take them from the steamer and put them in an ice bath for the same length of time as you cooked them. Place the mushrooms in freezer-safe bags after straining the water to prevent them from drying out.

Sautéing

Using a tiny quantity of oil at a high temperature, sautéing swiftly softens and browns food over dry heat.  Vitamins may be saved by cooking this method without the use of water. Cooking with fat may also help the body absorb antioxidants and other plant elements. 

Add fresh mushrooms and a little quantity of heated oil or butter to a big pan and increase the heat to medium-high. Cook for about 5 minutes. Cook for about 5 minutes, or until they’re nearly done. The mushrooms should be soft but not mushy at this point in the cooking process.

To cool down the mushrooms, remove them from the pan and set them on a paper towel or dish. If you want to save them for later, put them in a freezer-safe bag and freeze them.  Using any of these procedures, frozen mushrooms may be used in many ways. They function best when added to meals that are going to be cooked.

To defrost frozen mushrooms, what is the best way to do so?

It’s best to keep frozen mushrooms in your freezer for between nine and twelve months. Cooked meals like soups, casseroles, and stews may benefit from the use of frozen mushrooms. If you don’t have an oven, you may cook pasta, rice, or quinoa by adding frozen mushrooms to the grain while it’s boiling and cooking.

Frozen mushrooms may be softened by placing them in the refrigerator overnight to defrost before using them in a recipe that calls for longer cooking times.

Conclusion

In this brief guide, we answered the query, “Can you freeze cooked mushrooms?” and discussed ways to freeze mushrooms.

References

1. Czapski, J., and K. Szudyga. Frozen mushrooms quality as affected by strain, flush, treatment before freezing, and time of storage. J food sci, 2000, 65, 722-725.
2. Barros, Lillian, et al. Effects of conservation treatment and cooking on the chemical composition and antioxidant activity of Portuguese wild edible mushrooms. J Agric Food Chem, 2007, 55, 4781-4788.