FREEZE-DRYING RATES OF FISHES AND MEATS
Tokumatsu Tachiwaki and Seido Kawanaka
Department of Chemical Engineering and Materials Science,
Doshisha University, 1-3 Miyakotani, Tatara, Kyotanabe,
Kyoto 610-0321, Japan
Keywords: freeze drying, fish, meat, vacuum
ABSTRACT
The freeze-drying process has been studied theoretically as the capillary
model, the uniformly retreating ice front model, the zone retreating model
and the adsorption-sublimation model. So the freeze-drying rates are able
to be evaluated.
However, the actual freeze-drying rates of uniform eats such as fishes and
meats are not simply calculated because of the shortages of their physical
properties. Therefore the freeze-drying process has been studied
theoretically as the capillary model in this study. Assuming an operation
at factories, the freeze-drying rates of 24 kinds of fishes and meats were
experimentally measured in case of that the temperature of the heating
plate rose as the dryings proceeded. Based on the uniformly retreating ice
front model, a theoretical equation was obtained in order to estimate the
freeze-drying rates. The freeze-drying rates of fishes and meats were
calculated by the equation with the observed thermal conductivities of
dried fishes and meats. The calculated freeze-drying rates were in good
agreement with the observed freeze-drying rates.
|
