Factors affecting the quality of food dehydration are:
3. Air Speed or velocity
Raw material preparation
Drying time varies depending on the type of food dehydrator you use and the properties of your food for drying. Let us visualize what water must do in order to get discharged. The moisture from the center of the food must travel to the surface to escape. For example, apples can be cut into uniform slices with appropriate thickness for drying. Too thick slices will take longer time to dry. On the other hand, too thin slices will crumble and break easily. Based on experience, inch inch (0.5cm) seems to be appropriate for most drying applications.
When using your food dehydrator, food is spread on drying trays which are then stacked up or placed into the specially designed drying chamber. It is important to spread the food evenly so that the entire surface of the food is exposed for drying. To ensure that all the food surfaces are exposed for drying, it is recommended that you periodically flip over the food.
Some food dehydrators may not have a uniform distribution of air but this can be easily resolved by rotating the trays every few hours so as to minimize the unevenness.
Drying time is in fact the most important factor in any drying process. However, it is affected by the air temperature and air velocity. Therefore, when considering these drying elements, remember that these are inter-related. The most common mistake made by people when drying foods is thinking that increasing the temperature to shorten the drying time. The recommended temperature for drying most products is 130degF.