Nothing beats the delicious aroma of sautéed mushrooms filling your kitchen or the rich, savory taste when paired with steak or roasted vegetables.
But anyone who’s bought fresh mushrooms knows what it’s like to open the fridge and see your caps shriveled and spotty. Or how you were so excited to add them to your latest dish, but now they’re a little slimy. You’re left wondering, “Are these mushrooms still good to cook with?”
Let’s look at the tell-tale signs that your mushrooms are going bad. Our mushroom experts at Monterey know exactly what to look out for, as well as the best tips for keeping your mushrooms as fresh as possible.
Signs of Expired Mushrooms: How to Tell If a Mushroom Is Bad
Mushroom Check! My Mushrooms:
Mushrooms aren’t exactly shy about letting you know when they’re reaching their expiration date! Here are some warning signs that your mushrooms are, or are getting very close, to their expected shelf life:
Mushrooms Are Slimy
In general, fresh mushrooms have a firm texture and may be slightly damp. Some varieties, like Oyster mushrooms, may be slick, which is different from slimy.
Sliminess is a sign that your fresh fungi are reaching a point of no return. A film of slime means the mushroom is getting ready to decompose. We always like to say, “If a mushroom is completely covered in slime, it’s past its prime!” Do not eat.
Dark Spots on Mushrooms
Spots aren’t necessarily a sign that your mushrooms are bad unless combined with other signs of expiration.
Some mushroom varieties naturally have dark spots or coloration, and some can even develop natural blotches, light bruises, or mild discoloration on the caps from handling during packaging.
If the spots are deep in color, noticeable, and present with other warning signs — like sliminess — those mushrooms aren’t fresh anymore. If the spots look at all like decay, throw them away.
Mushrooms Smell Bad
Fresh raw White or Brown mushrooms have a very subtle, natural smell that’s nearly unnoticeable. You’d have to stick them right against your nose to smell that earthy scent.
Mushrooms that are spoiled will likely have a distinctly bad odor. If you open the packaging and catch a nasty whiff, those mushrooms are starting to decompose and should be thrown away.
Mushrooms Are Wrinkled or Shrunken
Wrinkles are typically not a sign of expiration. It means your mushroom is starting to dry out from being in the fridge for too long and is often seen with diminished scale of the cap itself — in other words, it’s shrinking!
Mushrooms are 95% water, so they show signs of dehydration more distinctly than other produce items. If they are a little dry, consider immediately eating them or adding them to a liquid-based dish like soup to rehydrate and improve their texture.
Mushrooms Are Deformed or Cracked
No two mushrooms grow into the exact same shape, but a mushroom that is noticeably deformed can be a sign of shriveling from dehydrating in the fridge. Cracking of the cap can also indicate the mushroom is drying out.
Follow the same advice for wrinkled or shrunken mushrooms and eat immediately, or else throw them away.
FUN-GI FACT: Did you know decomposing mushrooms are a great food to add to your compost?
Their rich nutrient profile can be passed along to your plants in the garden.
Learn more about how we compost at Monterey Mushrooms!
How Long Do Fresh Mushrooms Last?
Growers like us at Monterey have made significant improvements in packing and shipping mushrooms, which means you have more time to enjoy them. You may even want to try using your fresh mushrooms in one of the fan-favorite recipes from our free More Flavor, Less Guilt Cookbook!
The average shelf life of mushrooms is 10 days from the day they were harvested. Because the ‘shrooms had to travel from the farm to a distribution center and then to your grocery store, the average mushroom package has seven days from the time it hits the grocery shelves to when it needs to be eaten.
One of the best ways to know how long your mushrooms are good for is to know where to find the expiration date on the packaging.
Determining Your Mushrooms’ Expiration Date
In order to pick the freshest mushrooms in the produce section, be sure to read the coded information on its packaging. Here at Monterey Mushrooms, our coding is on the right-hand side of most packages, as depicted below:
All mushroom packages, bags, and bulk cases are coded with the following: Location code(s) / Julian date / Line number / Military time.
You can identify expired mushrooms with the Julian date. It tells us what day of the year the mushrooms were harvested — starting with January 1. For example, mushrooms harvested on February 15th would display “046” as the second number of that code. By adding ten days to that Julian date, you can determine the expiration date; in this case, that would be on February 25, with a Julian date of “056.”
How Long Do Dried Mushrooms Last?
Many home chefs keep dried mushrooms on hand to incorporate in dishes ranging from soups and sauces to pasta and rice dishes. Many chefs and food industry professionals swear by dried mushrooms and consider them a pantry staple to take advantage of their slightly more concentrated taste and avoid the ten-day limit of fresh mushrooms. The best way to store dried mushrooms is to keep them in an airtight container or resealable plastic bag in a dark, dry place.
Best Ways to Keep Mushrooms Fresh
While your mushrooms will have their expected shelf life, you can reduce concerns about how long mushrooms last in the fridge before they go bad by storing them correctly.
Here are things to do to keep your ‘shrooms fresher for longer:
- The best place for mushrooms is in their original container since they are specifically designed by the experts to keep your food fresh. But after opening the package, you can move your mushrooms to a paper bag. Not plastic!
When you store your mushrooms in their original container until opened and then move them to a paper bag, the moisture they naturally retain is slowly released, whereas, in a sealed plastic bag, the trapped moisture will cause your mushrooms to age quickly.
- Know when and how to wash your mushrooms. Many think that after opening a package of mushrooms, the next step is to wash them like you would other produce before eating.
The texture and shelf life of mushrooms, however, can be affected by rinsing them directly under a running faucet. Instead, only clean your mushrooms prior to eating them by lightly brushing off any dirt using your hands or a damp paper towel.
- Freeze, marinate, or dehydrate your mushrooms to save for later! While fresh mushrooms are typically best eaten within 10 days of being harvested, you can extend the lifespan of your mushrooms by freezing or dehydrating them. From there, they can be added to soups, sauces, or other popular dishes.
Dehydrated mushrooms can even be ground into a mushroom powder and added to smoothies, soups, and more. Lastly, marinated mushrooms can be sealed in mason jars and stored for up to a year.
Take Mushrooms From the Shelves and Onto Your Plates!
The surefire way to make sure your tasty mushrooms don’t go bad is to eat them before they expire.
When you keep a few exciting recipes to whip up, you’re sure to use your mushrooms well before they’ve spoiled. At Monterey Mushrooms, we are expert mushroom growers who love to cook. That’s why we frequently post recipes on our site and put together incredible cookbooks.
In our More Flavor, Less Guilt Cookbook, we have over a dozen delicious recipes that are both fresh and low-calorie! Download your free cookbook, head to your local grocery store, and enjoy the deliciousness of mushrooms with confidence!
