Drying is not a precise method of food preservation, and the amount of drying time will vary depending on the equipment, moisture content of the fruit and the humidity in the air. Spray a cookie sheet or similar flat tray with vegetable spray, or line the tray with plastic wrap or parchment paper and spray with vegetable spray. Another option is to use the specially designed plastic sheets for electric dehydrators, and follow the manufacturer’s directions.
Oven drying: Test your oven to be sure it can maintain a low enough temperature; otherwise, “case hardening” may occur. This is the formation of a “crust” on the food, which prevents the interior from drying properly.
To test your oven, set it to the lowest setting. Place an oven-safe thermometer on the rack where food will be placed. Leave the oven door open 2 to 6 inches. Place a fan near the open door to circulate air. Check the temperature. If your oven can maintain a low enough temperature (140 to 145 F), it may be used for food dehydration. Racks should be 2 inches apart, with at least 3 inches of clearance from the top or bottom to the rack. See Table 1 for approximate drying times.
Note: Oven drying is not a safe procedure to follow if young children and pets are present.
Food dehydrator drying: Follow the manufacturer’s directions.