The three primary options for drying food at home are: sun dehydration, oven dehydration, and using a food dehydrator.
The advantages of sun dehydration are straightforward. Obviously, the sun provides a free, renewable energy source for food dehydration. However, sun dehydration requires a location that has several consecutive hot days of 90 to 95 degree Fahrenheit weather (32 to 35 degrees Celsius) and low humidity. Unfortunately, only a few areas in the United States, primarily the southwest, consistently have this type of climate. Solar dehydration is a variation of sun dehydration in which the sun's rays are collected inside a specially designed unit with adequate vents for the removal of moist air. Due to the enclosed unit, the temperature inside is usually 20 to 30 degrees Fahrenheit warmer than in open sunlight which results in a shorter drying time. Solar dehydration has advantages over sun dehydration, including more focused, higher temperatures and thus shorter drying times and protection from insects and other wind borne matter. However, inclement weather, limited ideal weather climates and a lack of control over the weather are the main problems with both sun dehydration and solar dehydration. All of these problems can cause inadequate dehydration which can spoil the drying food.
Oven dehydration involves drying food at temperatures between 130 and 150 degrees Fahrenheit (54 to 65 degrees Celsius) in your home appliance. With oven dehydration, you simply place food items on the wire racks in your oven, set the heat and leave the oven door slightly ajar to let moisture out. Advantages of oven dehydration include: a) an easy, practical way to experiment with dehydration, b) little to no additional investment is required, assuming an oven is already available, c) food protection from insects, dust and other outdoor matter that can plague sun dehydration and d) it does not depend on the weather. However, oven dehydration does have its disadvantages including: a) inefficient energy use given the oven’s size and cost, b) the danger inherent in leaving the oven door open while it is in use, c) the lack of air movement which is a component of food dehydration and moisture removal and d) many ovens cannot set temperatures below 200 degrees Fahrenheit (93 degrees Celsius).
In contrast to sun dehydration and oven dehydration, food dehydrators offer the most controlled, even and protected drying environment. Food dehydrators are specifically designed to eliminate the disadvantages of sun dehydration and oven dehydration by providing a constant ideal drying temperature combined with heated air that circulates via a blower or fan. Thus, the two main components in food dehydration – heat and air – are eminently controllable via the dehydration unit. A food dehydrator’s advantages, versus sun dehydration and oven dehydration methods, include: a) a more efficient usable unit and space, b) a temperature control that can precisely maintain a constant desired drying temperature, c) a fan that circulates the air, thus removing moisture and d) more efficient dehydration processing time.
Published 5/18/2009 12:00:00 AM