by: Val Hillers, Ph.D. , Extension Food Specialist
The least expensive method of preserving food is drying. It is also the oldest. Dried foods use less storage space than other ways of preserving food.Drying Fruits and Vegetables, PNW397 contains complete instructions for home drying. This extension bulletin may be ordered from WSU Bulletin Office.
Methods Of Drying
There are several methods of drying; each has advantages and disadvantages:
Sun dryingdepends on the temperature and the relative humidity outside. Sun drying can be used when the temperature is in the 90°s with low humidity and low air pollution. A major advantage is low cost. Drying trays, netting to protect against bugs, and the fruit are the only investment. Another possible advantage is the sun's sterilizing effect caused by ultraviolet rays that may slow the growth of some organisms. The disadvantage is that sun drying can only be done when the temperature is high and the humidity is low.
Solar drying is like sun drying, only better. The sun's rays are collected in a solar box; drying temperature is higher and drying time is shortened.
Oven drying. To dry small amounts at one time, the oven drying method can be used. There is little or no investment in equipment. You don't have to depend on the weather. Most foods can be dried in an oven.
Dehydrator drying. Dehydrators yield a better-quality dried product than any other method of drying. A dehydrator should have a heat source, a thermostat, and some method of air circulation.
Testing For Dryness: Home-dried foods should be conditioned before packing because different pieces of food dry differently. Too much moisture left in a few pieces can cause the whole batch to mold.
Place dried foods in a tightly closed large container. Stir or shake every day for a week. This will equalize the moisture (those pieces that are too dry will take some of the moisture from those that are too wet). If the dried food still seems too moist, return to the dryer for several more hours.
Storage Of Dried Foods: Dried foods maintain the best quality and nutritional value if they are used in less than 12 months. Moisture must be kept from dried foods when they are stored or the food could mold.
Containers suitable for freezer use also work for dried foods. Heat-sealed plastic bags and plastic or glass containers with tight-fitting lids are excellent for storage. Some people prefer to store dried food in the freezer because it takes up little space and there are no problems with mold or insects.