Fresh mushrooms last 5 to 7 days in the refrigerator when stored in a paper bag, and as few as 1 to 3 days in plastic. The difference comes down to moisture control. Mushrooms are 85 to 95 percent water, and unlike most produce, they have no protective skin to slow moisture loss or block bacteria. How you store them determines whether they stay firm and flavorful or turn slimy within days.
Why Mushrooms Spoil So Quickly
Mushrooms are among the most perishable items in your kitchen, and it helps to understand why. After harvest, they keep “breathing” at an extremely high rate, consuming oxygen and releasing carbon dioxide, heat, and moisture. This respiratory rate accelerates as temperature rises. When stored at room temperature versus refrigerator temperature, mushrooms lose moisture nearly twice as fast. That moisture leaves the mushroom flesh and collects on whatever surface surrounds it. If that moisture has nowhere to go, it pools around the mushrooms and creates ideal conditions for bacteria and mold.
The lack of a cuticle, the waxy outer layer that protects most fruits and vegetables, means mushrooms are essentially exposed flesh from the moment they’re picked. They bruise easily, absorb water readily, and offer no natural barrier to microbial attack. This is why storage choices that seem minor for other produce, like the type of bag or container, make a dramatic difference for mushrooms.
The Best Container for Refrigerator Storage
A brown paper bag is the single most effective everyday storage method. Paper absorbs excess moisture released by the mushrooms while still allowing airflow, reducing the humidity inside the bag by roughly 45 percent compared to plastic wrap. In one large study, mushrooms stored in plastic bags were 60 percent more likely to develop mold or bacterial growth within just 72 hours at refrigerator temperature. Mushrooms in breathable packaging stayed firm, kept their natural aroma, and remained in good condition for up to a week.
Here’s a quick comparison of common storage methods:
- Paper bag: 5 to 7 days. Mushrooms stay firm with minimal sliminess.
- Plastic bag (sealed): 1 to 3 days. Moisture gets trapped, leading to rapid sliminess and decay.
- Original store tray (opened): 2 to 4 days. Performance drops quickly once the plastic overwrap is removed.
If you don’t have a paper bag, a bowl lined with a paper towel and loosely covered with another paper towel works well. The goal is the same: absorb released moisture while letting the mushrooms breathe. Avoid airtight containers unless you line them generously with paper towels and leave the lid slightly cracked.
To Wash or Not Before Storing
Don’t wash mushrooms before putting them in the fridge. Any added moisture accelerates spoilage. Wait until you’re ready to cook them.
When that time comes, you may have heard that mushrooms should never touch water because they’ll absorb it like sponges. This is somewhat exaggerated. One practical test found that a pound of mushrooms rinsed under running water absorbed only about 0.8 ounces of moisture. The key is to rinse briefly under running water rather than soaking them. A quick rinse followed by a pat-down with a paper towel removes dirt effectively and won’t ruin your sear. Submerging mushrooms in a bowl of water, however, will make them waterlogged and mushy.
Wild mushrooms are a different story. Morels, for example, have a honeycomb texture that harbors grit and tiny insects, so they typically need a soak in salted water before cooking. But this should happen right before you cook them, never before storage.
Shelf Life by Variety
Not all mushrooms hold up equally in the fridge. Button and cremini mushrooms are the sturdiest everyday options, lasting a full week in a paper bag. Portobellos, being larger and more exposed, tend to dry out faster and are best used within 5 days. Shiitake mushrooms fall in a similar range, about 5 to 7 days when kept dry.
Oyster mushrooms are more delicate, typically lasting 4 to 5 days under good conditions. Their thin, fan-shaped caps lose moisture quickly and become rubbery if they dry out too much, so keeping them loosely wrapped is important.
Wild foraged mushrooms like chanterelles and morels have a much shorter window. Chanterelles are notoriously perishable and rarely last more than a couple of days in the fridge. The best approach with wild mushrooms is to store them unwashed, in a paper bag, and use them as soon as possible. If you can’t cook them within a day or two, move to a longer-term preservation method.
How to Freeze Mushrooms
Freezing extends mushroom storage to several months, but raw mushrooms don’t freeze well. The high water content forms ice crystals that rupture cell walls, leaving you with a mushy, watery mess when thawed. Cooking them first solves this problem.
You have two good options. Sautéing is the simplest: cook sliced mushrooms in a bit of oil or butter until they release their liquid and it evaporates, then cool completely before transferring to freezer bags. Blanching is the other route and works especially well for whole or halved button, cremini, and portobello mushrooms. Drop them in boiling water for about 2 minutes, transfer immediately to ice water to stop the cooking, then drain and pat thoroughly dry before freezing.
Spread the prepared mushrooms in a single layer on a baking sheet and freeze for an hour or two before transferring to bags. This flash-freeze step prevents them from clumping into one solid block. Frozen mushrooms keep their flavor well, though the texture will be slightly softer than fresh. They’re best used in soups, sauces, stir-fries, and other cooked dishes rather than eaten on their own.
Drying for Long-Term Storage
Dehydrating is the best method for truly long-term storage, and dried mushrooms develop a concentrated, savory flavor that fresh ones can’t match. You can use a food dehydrator or a conventional oven.
Slice mushrooms to a uniform thickness of about a quarter inch. Set your dehydrator or oven to 140°F (60°C). In a dehydrator, the process takes 8 to 10 hours. A conventional oven takes up to twice as long, and you’ll want to prop the door open slightly for airflow. For larger pieces, flip them every 3 to 4 hours. Mushrooms are done when they snap cleanly rather than bending.
Store dried mushrooms in an airtight container in a cool, dark place. They’ll keep for 6 to 12 months. To rehydrate, soak them in hot water for 20 to 30 minutes. Save the soaking liquid, too. It makes an incredibly flavorful base for risotto, gravy, or soup.
Storing Cooked Mushrooms
Cooked mushrooms follow the same rules as any other leftovers. Keep them in an airtight container in the refrigerator and use within 3 to 4 days. If you’ve cooked more than you can eat in that window, freeze them. Cooked mushrooms hold up well in the freezer for 3 to 4 months.
Signs Your Mushrooms Have Gone Bad
Fresh mushrooms should feel dry to the touch, smell earthy and mild, and have a firm, springy texture. When they start to turn, the signs are unmistakable:
- Sliminess: A sticky or slippery coating is the clearest sign of bacterial activity. Slimy mushrooms should be discarded.
- Dark spots: Minor bruising from handling is normal, but widespread dark or black patches indicate active decay.
- Sour or ammonia-like smell: Fresh mushrooms smell earthy. If they smell sour, alcoholic, or like ammonia, fermentation or bacterial growth is underway.
- Wrinkled, shriveled texture: This means the mushrooms have lost too much moisture. They’re not necessarily unsafe, but the flavor and texture will be poor.
A single slightly soft mushroom in an otherwise good batch can be trimmed and used. But if multiple mushrooms are slimy, discolored, or smelly, toss the whole batch. Mushrooms that have visible mold, even just on one or two in the container, should all be discarded, since mold spores spread invisibly.