How to turn your oven into a dehydrator

Here's how to dehydrate foods in even the most average of ovens.

Alina Bradford CNET Contributor
Alina Bradford has been writing how-tos, tech articles and more for almost two decades. She currently writes for CNET's Smart Home Section, MTVNews' tech section and for Live Science's reference section. Follow her on Twitter.
Alina Bradford
3 min read

Your oven is waiting!

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Dehydration is one of the easiest ways to preserve food. You don't need to buy special jars, preservatives or special equipment. You don't even need to buy a dehydrator. Your oven, whether it be full-sized oven or a toaster oven, can dehydrate food perfectly in the same amount of time.

Tools for oven dehydration

The tools for dehydrating food in your oven are simple and you probably already have them in your kitchen. You'll need:

  • Lemon juice (for fruits)
  • Mandolin slicer or knife
  • Wax paper
  • Cookie sheets (or any flat pan)
  • Spatula

Prepping the foods

How you prep foods depends on what you are dehydrating. Here are some tips for the best results:

  • To prevent fruits from turning brown, soak them in a half-and-half mixture of lemon juice and water for five minutes before drying.
  • For foods to dry evenly and thoroughly, the pieces need to be the same size and thin. Around ¼-inch (0.63-centimeter) slices are best. If your knife skills aren't the best, try using a food mandolin.
  • Fat can make dried foods rancid. It can also scorch during oven drying. Cut all visible fat from meats and use lean cuts.
  • Put a sheet of wax paper on your cookie sheet and lay your foods on top. This will prevent a sticky situation when you try to remove the foods from the sheet.
  • You can place large pieces of meat directly on your oven's rack, but use paper towels to blot any excess marinade so that it doesn't drip down onto the heating element.

Bring the heat

The temperature of your oven is key for proper dehydration. Too hot and your foods will scorch or burn. You'll want the oven's temperature to be under 200 degrees Fahrenheit (93.3 Celsius) for the best results. Unfortunately, most ovens won't give you many temperature options under 200 degrees. Don't worry. Simply set your oven to "warm" and you'll be all set. If you do have temperature options, 120 degrees F (49 degrees C) to 140 degrees F (60 degrees C) is usually optimal for a wide range of foods.

In the beginning of the drying process, you can speed things along by cranking the heat up to 150 degrees to 160 degrees F (65 degrees to 70 degrees C) until the surface moisture has evaporated. As soon as the surface of the foods seem dry, lower the heat to 120 degrees F (49 degrees C) to 140 degrees F (60 degrees C).

Dehydrating for the win

There are a few things to remember while you dry foods in the oven:

  • Many ovens have hot spots that can cause some areas to dry faster than the others. Throughout the drying process, be sure to rotate the pans so they all dehydrate uniformly. This is particularly important when using an toaster oven because there usually isn't a fan to distribute heat evenly.
  • Flip the foods over several times throughout the drying process so that all sides get dried evenly.
  • Space the pans 1.5 inches (2.54 cm) apart so that air can circulate around the foods as they dry.
  • Oven drying times vary, depending on the food. Plan on it taking 6 to 10 hours. Drier foods take less time, while juicier foods take longer. If the food is sticky or moist, it isn't done drying.