By Marilyn Wells

Cooperative Extension

One of the oldest methods of preserving summer fruits and vegetables is with the drying method.

Drying foods is simple, safe and doesn’t require refrigeration. Dried foods are perfect for backpacking, camping and snacking. Meat jerky, nuts and seeds provide good sources of protein for meals or snacks.

Fruit chips provide energy and dried vegetables can be rehydrated for a meal or a soup. While you are setting up camp, add water to the veggies and reconstitute them for 1 to 2 hours. Then prepare the vegetables in the same water to retain the vitamins.

When you dry foods, bacteria, yeasts and molds cannot grow and spoil the food because the moisture has been reduced.  The food will become smaller and lighter in weight making for a nutritious snack.

Foods can be dried in the sun, in an oven or in a food dehydrator by using the combination of warm temperatures, low humidity and air current.

For drying fruits, choose fruit without blemishes, wash, halve and slice into thin slices. To prevent darkening, dip into ascorbic acid mixed with water or a juice loaded with vitamin C.

For drying vegetables, wash and slice in uniform pieces. Blanch the vegetables in boiling water to stop the enzyme action which causes loss of color and flavor during drying. Immediately, dip into ice cold water to stop the cooking process. Lay the slices individually on the tray so there is air circulation all around.

Dry fruits until they have 20% moisture left  by cutting several pieces in half. There should be no visible moisture and no moisture can be squeezed from the pieces. The fruit should remain pliable. Let the fruit cool completely and pack it loosely in plastic or glass jars. Seal the container and let it stand for 7-10 days. If condensation appears, return the fruit to the dehydrator for more drying. Vegetables should be dried until they are brittle or “crisp”. They should contain only 10% moisture. They should be crisp enough to shatter if hit with a hammer.

A food dehydrator is a small electrical appliance used for indoor drying of foods. It has a heating element, a fan and vents for air circulation. It is designed to dry foods at the correct temperature of 140 degrees F. Food dehydrators can be purchased at many locations and the instructions will give you step by step directions for optimum food drying. The drying process may take from 6-36 hours depending on the type of food.

For outdoor drying, look for a hot, dry, breezy day with the temperature at 85 degrees or higher. Humidity should be no higher than 60%. Foods must be covered or brought inside at night due to the condensation of the cool night air. Outdoor drying racks can be easily constructed with cement blocks and stainless steel screens. Lay a sheet of aluminum or tin on the ground to reflect the heat to the dryer. Place cement blocks on either end of the metal sheet and the stainless steel screen over the top of the blocks. Lay food out so that the pieces are not touching. Place another screen on top of the food.

If you have an oven, you have a dehydrator even though a regular oven will take 2X longer to dry the food than a dehydrator. An oven works well to dry meat jerky, fruit chips or mushrooms. Oven drying is a slower method unless you have a convection oven with the built in fan for air movement. Optimum temperature for drying food is 140 degrees F. so if your oven does not register that low, it cannot be used as a dehydrator. At a temperature higher than 140 degrees F., you will cook the food instead of drying it. Cooking will not let the interior moisture escape so the food will eventually mold. Do not raise the temperature above 140 degrees during drying. Place a cake cooling rack on a cookie sheet and lay thin slices of food on top of the cookie sheet. Allow the door to be left 2 to 6 inches ajar for air circulation.

For more information contact the NC Cooperative Extension, Davie County Center, Marilyn_Wells@ncsu.edu  336-753-6100.