The colorful gems you found sprinkled throughout cereals as a child were often the best part of breakfast, and the pearly white cubes floating on top of hot chocolate can still make cold winter days warm. For a snack or an addition to breakfast cereal or cocoa, you need to dry marshmallows 6 to 24 hours, or until they reach the desired dryness. For long-term preservation, dry marshmallows 24 to 36 hours, or until hardened all the way through.
Fresh or Store-Bought Marshmallows
You get better results from dehydrating homemade marshmallows than you do store-bought ones. Store-bought marshmallows contain an array of preservatives added to keep marshmallows fluffy and moist -- the opposite of what you want in this preparation. Some brands of marshmallows contain combinations of gum arabic, xanthan gum and lecithin that nearly prevent drying.
Homemade marshmallows, on the other hand, contain only gelatin, sugar and sugarcane syrup, so nothing impedes the drying process. Food colors, oils and extracts let you flavor your marshmallows as you like. You can find concentrated flavorings in the cake aisle of the supermarket. As a guideline, you need about12 to 15 drops of flavoring per 1-pound batch of marshmallows, but add it to taste for best results.
Making Homemade Marshmallows
To make marshmallows at home, dissolve 1 packet of unflavored gelatin and 2 parts, or 2/3 cup, granulated sugar in 1 part, or 1/3 cup, of water in a saucepan over low heat on the stove. Add the gelatin-sugar mixture to a stand mixer and use the whisk attachment to combine it with 1/2 cup of light corn syrup, food coloring and flavoring on high speed until it reaches the soft peak stage, about 15 minutes. Grease a rimmed cookie sheet and dust it with confectioner's sugar. Then spread out the marshmallow mixture on the sheet in an even layer using a rubber spatula.
You have to operate the oven at a temperature low enough to speed the evaporation of marshmallow's moisture without cooking them. To dry marshmallows in your oven, set it on Warm and let it heat for 10 minutes, then turn it off. Turn the oven light on and the fan, if these functions operate independently of the heating element. Place the marshmallows in the oven and let them dry for one week before checking. The marshmallows should feel firm but pliable when ready. Cut the marshmallows into squares with a spray-oiled pizza wheel or a sharp knife.
Air drying is your next best choice for drying marshmallows -- if your area has less than 60 percent humidity and the temperature is 75 degrees Fahrenheit or above. To dry marshmallows outdoors, set the pan in a shady area or an area out of direct sunlight. Cover the pan with a layer of cheesecloth and let the marshmallows dry until they reach the desired dryness. The exact drying time varies depending on the weather, but check the marshmallows every day until they dry.
You can use a rectangular dehydrator to dry marshmallows, too. Round dehydrators have a tray system that makes it difficult to spread marshmallows in an even layer. Rectangular dehydrators have a sliding tray system that makes spreading the marshmallow in an even layer easy, which makes them dry uniformly. Line the dehydrator tray with a piece of parchment paper and dry the marshmallow at 80 degrees Fahrenheit for 6 to 24 hours, or until they reach the desired dryness. Start checking the marshmallows after 6 hours of drying.