You can air-dry, oven dry or use a dehydrator to dry your mushrooms.  For the purpose of this article, I will be focusing on using the dehydrator.

Why dry mushrooms?

Mushrooms rehydrate to almost the same consistency as fresh mushrooms, so this is a great way to store them for longer periods than they would last any other way.  You retain most of their nutrients when dehydrating, and they also tend to pick up better flavor.  They also grind down well into a powder which is great for getting mushroom taste into dishes that you may not want to actually feel them.  My husband can’t stand the texture of mushrooms, but he enjoys dishes made from soups that contain them.  This has been a great way to include homemade ‘cream of mushroom soup’ in the meals we all enjoy.  You could also mix powered mushrooms into sauces that normally contain them to avoid the texture but still enjoy the flavor.  You can actually buy dehydrated mushrooms, but if you have a dehydrator search out mushrooms when they are on sale or clearanced because they are at or near their sell-by date for the best deal – or learn to grow them yourself.

How To:

Wash your mushrooms to get any dirt off, then slice them in even thicknesses about 1/4 – 1/2 inch.  You can buy mushrooms already washed and sliced if you desire. Lay them on your dehydrator trays in a single layer and turn it on to the vegetable setting or around 110F.  Dry them for 4-8+ hours.  How long dehydrating takes depends on how thick you have sliced them.  When they are dry, they will feel extremely light and should crack like a dry cracker without giving you too hard a time.

Store in an airtight container in your pantry.  They will last at least a year so long as the conditions are right.  Avoid lots of exposure to light, heat and of course keep it away from moisture!

To Use:

To rehydrate quickly, pour boiling water over the amount of mushrooms you want to rehydrate and cover, letting it sit.  This will rehydrate them quickly, however, their flavor may get lost in the soaking liquid.  To rehydrate slowly, soak them 30 minutes to overnight (thinly sliced mushrooms should rehydrate quickly) in room temperature water.  They will retain more flavor this way.  Or, add dry mushrooms right to soup and they will rehydrate as it cooks.

You can save the soaking liquid, which has flavor, and use it in future cooking.  Beware of grit though, it will settle at the bottom of the container you are soaking your mushrooms in.  Pour the liquid slowly from the container and stop before the grit pours out.

Rinse your mushrooms before use – it won’t remove flavor but it will remove grit.

Equivalents: 

Most recipes include mushrooms as an ingredient by weight.  You can weigh a portion of your mushrooms – perhaps by ounce or pound – and keep them on a  separate tray(S) then weigh or measure them by weight or cup after drying so you have an idea of how they will convert.

Here are some helpful notes:

1 pound fresh button mushrooms = 20 to 24 medium mushrooms 
• 1 pound fresh button mushrooms = 5 cups sliced 
• 1 pound fresh = 6 cups chopped 
• 1 pound fresh button mushrooms = 2 cups sliced and cooked 
• 1 pound fresh = 2 cups cooked 
• 1 pound fresh mushrooms = 3 ounces dried and reconstituted
8 ounces sliced fresh mushrooms = 1-1/2 ounces dried mushrooms plus 3/4 cup boiling water
1-1/2 ounces dried mushrooms = 8 ounces sliced fresh
• 1-1/2 ounces dried mushrooms = 4 ounces drained canned sliced
• 1 Tablespoon powdered mushrooms = 3 Tablespoons whole dried mushrooms
• 1 Tablespoon powdered mushrooms = 4 ounces fresh mushrooms
1 Tablespoon powdered mushrooms = 2 ounces canned mushrooms