Dehydration or drying, is one of the oldest and gentlest methods of food preservation. Food dehydration works by removing only the water content from the ingredients. All other nutrients remain, and become highly concentrated. Dried foods are extremely nutritious, easy to prepare and store, and light weight to ship.
Because dehydration takes place at moderate temperatures, the ingredients are still considered raw. The only exceptions are the meat and egg ingredients, which are dehydrated at high enough temperatures to kill any bacteria present and are therefore essentially considered 'cooked'. This is because they must be human-edible grade, to enter our manufacturing facility.
The removal of moisture prevents enzymatic activity, which can lead to browning and decomposition of foods, and also prevents the growth of bacteria, yeast and molds. Dehydration does not actually destroy or kill the food enzymes, as occurs in baking and freezing or high pressure processing such as extrusion. Enzyme activity in dehydrated foods is simply suspended, until the food is rehydrated.
A remarkable example of the way dehydration preserves without destroying, is in Africa, where scientists have discovered live fish being hatched from fish eggs, that have been dehydrated in the sun, during droughts that sometimes last for years. When the rains fall, the lakes and rivers refill with water to rehydrate the eggs - and live fish emerge. The eggs are actually preserved and remain viable throughout the natural dehydration that takes place.