Rapid Thawing Device by Radio Frequency Dielectric Heating

Abstract

　Thawing method by using dielectric heating can rapidly heat food with less temperature difference between the surface layer and inside of the food, because the food itself becomes a heat-generating element. Compared with microwaves (300MHz～30GHz), radio frequency waves (3MHz～300MHz) are so suitable for thawing that hot spots and thermal runaway hardly occur. The half-thawing state at slightly lower temperature range -5 to -1°C than the freezing point is called “Tempering”, which is distinguished a complete-thawing state. “Tempering” has been variously utilized for frozen food processing. Herein we introduce thawing cases and an overview of batch type and continuance type radio frequency thawing equipments.