State University Extension
Preserving Food Safely - 01600518
1. Trays must be at least 1 1/2 inches narrower than the
inside of the oven to allow for air circulation. Allow at
least 2 1/2 inches between trays and 3 inches of free space
at the top of the oven. Cheesecloth may be spread over the
trays (under the food) to prevent small pieces from falling
between the slats.
2. Load two to four trays with no more than 4 to 6 pounds
of prepared vegetables distributed among them. Vegetable
pieces should be in a single layer. More than one kind of
vegetable can be dried at the same time. Strong-smelling
vegetables should be dried separately.
3. Place an accurate and easily read thermometer on the
top tray toward the back.
4. Preheat the oven to 160 degrees Fahrenheit (71 degrees
Celsius), and then add the loaded trays. Prop the door
open at least 4 inches.
5. Place a fan outside the oven in such a position that
air is directed through the opening and across the oven.
Change the position of the fan frequently during drying to
vary the circulation of the air.
6. Maintain the temperature at 140 degrees Fahrenheit (60
degrees Celsius). It takes less heat to keep the
temperature at 140 degrees Fahrenheit as drying progresses,
so watch the temperature carefully toward the end of the
7. Examine the vegetables often, and turn the trays
frequently. At the start of the drying process, there is
little danger of scorching, but when nearly dry, the product
may scorch easily. Even slight scorching destroys the
flavor and may lower the nutritive value, so be careful not
to allow the temperature to rise above 140 degrees
Fahrenheit, especially during the latter stage of drying.
NOTE: Tests for dryness will come with experience. The
approximate drying times are merely a guide to judging
proper dryness. Most vegetables will be brittle when dry
and would shatter if hit with a hammer.