Food dehydrators are small home appliances for drying fresh foods yourself. They come in a wide variety of sizes and capabilities, and can dry fruit, vegetables and meats. They work by very gently heating the air and blowing it throughout the food drying area. It can take a number of hours, or even days, to adequately dry and preserve juicier items.
If you are an avid gardener and always grow more produce than you can consume during the summertime, a food dehydrator might be a good investment. You can stock up on dried vegetables and ensure yourself home-grown vegetable soup throughout the winter months. If you like camping and hiking, making your own trail mix is surely appealing. But beware - buying produce to dry will probably wind up costing you more than purchasing a similar quantity of dried fruit and vegetables. Large food processors can buy and dry produce much more cost effectively than an individual consumer can.
Food dehydrators blow air either up from the bottom heating element, or horizontally from a heater placed in one side. The horizontal flow has the advantage that you can dry a mixed batch of things without worrying about flavor mixing; your dried apples taking on the flavor of the beef jerky drying below them, for instance. If this isn't an issue, then the bottom-heating dehydrators should serve you adequately.
Food to be dried in a food dehydrator is sliced very thinly for faster drying, and laid out in single layers on thin stacking trays, which are vented to allow air to flow through them. The trays are loaded into the unit and then left to dry. Some items will dry quicker than others and should be removed or they will become brittle. Very juicy foods like oranges and tomatoes can take quite a period of time in the food dehydrator, and should not be mixed with quicker drying foods such as carrots and potatoes.
If you want to make your own meat jerkies, look for a good drying-marinade recipe. Most food dehydrators will come with a recipe book that should include marinades for meats. Make sure that the unit you are using will heat the meat to temperature high enough to kill e-coli and other bad bugs.
Food dehydrators consume very little electricity; much less than an oven, for instance. One utility company estimates that the cost of operating a food dehydrator continuously for 24 hours is $0.49. Compared to the cost of operating a coffee maker ($1.63 for 24 hours), this is quite a bargain. So don't let the fear of high electric bills hold you back from drying as much of the harvest as you wish.