Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)


Nutrition, Dietetics, and Food Sciences

Department name when degree awarded

Food Science and Technology


D. K. Salunkhe


Many innovations have been attempted to shorten drying time or improve dehydration techniques for foods. Despite the recent advances in science and technology the bulk of dried fruit production throughout the world, over 1 1/2 billion tons (dry basis), is prepared by the energy of the sun (Copley and Van Arsdel, 1964), However, other techniques and processes for food dehydration and preservation are occupying more prominent positions in the overall production of dehydrated foods, particularly in the more advanced countries. Economics notwithstanding, it is readily apparent that dehydration as compared to sun-drying offers at least two main advantages. It is more sanitary and it is independent of inclement weather and thus of geographies. These two reasons arc perhaps among the chief ones for the increasing technical developments in dehydration by procedures such as cabinet drying (Beavens, 1944), vacuum drying (Schroeder and Schwarz, 1949), freeze drying (Lawler, 1963) and foam-mat drying (Morgan and Ginnette, 1960). They are perhaps also the reason for continuing research on new and improved dehydration processes which may be adaptable to certain types of products. In this continuing search, electromagnetic waves, which are similar to the more familiar light or radiowaves but differ in frequency and wavelength, have received little attention.