Drying of food

Drying food is inexpensive. A commercial dehydrator can easily pay for itself in a summer or two.

This is one of the oldest preservative techniques; the sun, fire, and mounds of host sand have been used of dry foods since prehistory.

For most foods, the drying nutritional value retained is about the same as with freezing. Drying has a lower heat exposure than canning and therefore destroys fewer vitamins.

Drying reduces the water activity, thus preserving foods by avoiding microbial growth and deteriorative chemical reactions.

The effects of heat in microorganisms and the activity of enzymes are also important in the drying of foods. 

While sun drying used to be the most common treatment for prunes, raisins, apricots, and figs, forced hot air-drying is now widely used because it is more predictable.

Home and restaurant cooks can use the oven or small electric driers whose temperature is easier to control.

Drying conditions profoundly influence pasta cooking quality. If pasta dries too quickly the surface will harden and the pasta may fracture due to stress as moisture trapped within attempts to migrate to the surface.
Drying of food