ABSTRACT
Variables ................................................................................................. 232 Greeks ..................................................................................................... 233 Superscript .............................................................................................. 233 Subscripts ................................................................................................ 233
References .......................................................................................................... 234
The ancient Peruvian Incas of the Andes knew the basic process of freeze-drying food. Freeze-drying or lyophilization is the sublimation or removal of water content from frozen food. The dehydration occurs under a vacuum, and the wet zone is frozen during the whole process so that nearly perfect preservation results. The Incas stored their potatoes and other food crops on the mountain heights above Machu Picchu (Carter, 1964). The cold mountain temperature froze the food and the water inside slowly vaporized under the low air pressure of the high altitudes; basically, the foods were freeze-dried.
