PRODUCT CATALOGUE PRODUCT CATALOGUE | Page 9

DEDICATED DRYING MACHINES MANUFACTURER Rehydration of Dehydrated Foods Dehydrated products readily take up moisture when immersed in a liquid medium, leading to significant changes in their thermophysical properties. The rehydration kinetics, the structural properties (apparent density, true density, specific volume and internal porosity), the viscoelastic behavior (compression tests), and the flavor losses were taken care during rehydration of various fruits and vegetables. The effect of temperature on the above properties is also important for some fruits and vegetables dehydrated by different drying methods (Convective i.e Hot Air Drying, Vacuum Drying, Freeze Drying, and Osmotic Drying). The structural properties of rehydrated foods appear to show a hysteresis compared to those measured during dehydration processes. The shrinkage that takes place during dehydration prevents rehydration and produces products with lower apparent density and higher porosity. Structural damages that occur during drying seem to affect also the viscoelastic behavior of the rehydrated foods and the hysteresis phenomenon is also observed at the textural properties, with a degree varying between the different drying methods. The characteristics of dehydration and rehydration kinetics determined the product quality. Dedicated Drying Solutions Corporate Office KDM Analytical B-2/41 First Floor, Rohini Sector-16, Delhi-110089 India Tel +91-9643480893 +91-9540666954 E -mail [email protected] Application Lab D-198, Mundka Industrial Area Delhi-110081 web www.kdmanalytical.com