Fresh mushrooms make a great addition to any kitchen. In stir-fries, sauces and many other dishes, I love mushrooms rich in umami. They are a great choice for Meatless Monday meals because they are dense and meaty. A simple but delicious bowl of mushroom broth is a great way for a fall evening to warm up.
Fresh mushrooms can be expensive and have a short shelf life. Tossing whole packages of slimy mushrooms can not only be a waste, but it also costs money. To maximize their shelf life, six storage options were tested. The winner kept the mushrooms fresh for a full 10 days. It also enhanced their flavour. These are the methods that we tried and how they performed.
The Methods We Tested
I searched the internet to find different mushroom-storage methods. Because mushrooms are best preserved fresh, I didn’t wash them before storing them. Another common opinion was that mushrooms should not be kept in a crisper. This is again due to moisture. You can adjust the humidity in most crispers, but many people choose the high-humidity setting for leafy greens and mushrooms.
After doing my research, I narrowed down my options to six. Six packages of whole white button mushrooms were purchased, the most popular variety in the grocery store. I put one on the middle shelf and then took the rest to a large bowl. Next, I separated the 10 remaining mushrooms into separate batches for testing.
Ratings and judging criteria: According to various sources, mushrooms can last between seven and fourteen days in the refrigerator. Because all methods performed equally for the first five days, I decided to test them for 10 days. I monitored the status every day and, after 10 days, I gave the mushrooms a rating of 10.
Mushroom Storing Method: Plastic Bag and Paper Towels
- Rating: 1/10
This method: I found this advice via FoodNetwork.com. It sounded simple enough. I wrapped the mushrooms with paper towels and put them in a plastic bag. The theory is that the paper towels absorb moisture while the open bag allows for ventilation.
Results After ten days, all of the mushrooms in the bag had a thin slime layer. The mushrooms had a strong odour, and four of the 10 were discoloured.
What I learned: Both the paper towel and plastic bag were damp. This leads me to believe this storage method was trapping moisture instead of preventing it. This batch became slimy quickly — it was around day six that things started to go downhill.
Mushroom Storing Method: Use a bowl with plastic wrap
- Spoilage 50%
- Rating: 3/10
This is how it works: I put the mushrooms in a large glass bowl that was big enough to keep them from crowding. I wrapped the bowl in plastic wrap and punched five holes into it. It was mostly left alone for the 10 days, as I didn’t want it to be unwrapped during the testing period.
The result: The bowl’s bottom was slightly damp. Half of the mushrooms had slime on the bottom, but it wasn’t as severe as the plastic bags. Two mushrooms were significantly darker than others.
What I learned: Half of the mushrooms were likely safe to eat. However, I decided to throw the entire batch. This test is similar to the one with plastic bags. It suggests that plastic film may not be the best friend for mushrooms.
Storing Mushrooms in Original Container
- Rating: 3/10
This method: The package of mushrooms was taken straight from my grocery bag to the middle shelf of the fridge. I let the mushrooms sit for 10 days without checking them visually.
The results: On day 10, the mushrooms looked the same as they did when I brought them home. They looked perfectly white, with no visible discolouration. There were water droplets inside the container. This is likely why four mushrooms had slime on them, and one had mould. The mushrooms also had a faint odour.
The takeaway: I was disappointed that this was (or was) my preferred storage method. As long as the mushrooms are used up within five days, I have never had any issues with them going bad. This method works well for temporary storage and is certainly the most convenient.
Mushroom Storing Method: Bowl and Paper Towels
- Rating: 6/10
This is how it works: I lined a large glass container with paper towels, spread the mushrooms out and covered it with another layer. This method allowed me to monitor the freshness of the mushrooms every day, unlike the plastic wrap-covered bowl. They stayed fresh and dry for five days.
The result: At the end of 10 consecutive days, two mushrooms had developed a slimy film while half of them developed dark spots. The paper towels were dry.
The takeaway: While it’s a big improvement over the plastic version, nobody wants slimy mushrooms. Although I may be cautious, I would not eat any of the left mushrooms even if they looked good.
Mushroom Storing Method: Paper Bag
- Rating: 6/10
This is how it works: Harold McGee, a food writer, preferred this method. He transferred the mushrooms from the original container to a brown bag and placed them in the refrigerator.
The results were All the mushrooms were slightly dry and wrinkled. Four mushrooms had dark spots. There was no discernible smell.
The takeaway: The brown paper bag kept moisture away, even though the dark spots were a little concerning. I decided to discard the mushrooms with dark spots and cook the rest of them. Cook’s Illustrated states that older mushrooms can be eaten. Their guide on mushrooms states that older mushrooms have a deeper, earthier and more mushroomy flavour than unblemished ones.
Mushroom Storing Method: Paper bag with paper towels
- Rating: 7/10
This is how it works: I lined a brown paper bag using a folded paper towel and then placed the mushrooms in the bag.
The result: There were no slimy mushrooms at the end of the 10 days. The mushrooms turned darker were three, and the rest looked more tanned. Three mushrooms also had a slight wrinkle.
The takeaway: The combination paper towel/paper bag effectively kept the moisture under control, so the mushrooms weren’t squished. The mushrooms in a paper towel-lined bag did slightly better than those in unlined bags.
The Best Takeaways
Plastic traps moisture, so mushrooms can end up in damp containers or bags, which can cause discolouration, mould and slime. Although button mushrooms should be eaten within five days of purchase, brown paper bags can help extend their shelf life. Plus, you might end up with a more flavorful mushrooms dish.