Kinetics and Quality Aspects of Beetroots Dried in Non-Stationary Conditions

This paper presents the results of experimental studies on convective drying of beetroot (Beta vulgaris L.) in non-stationary conditions. The effect of stepwise changing air temperature and pretreatment methods such as osmotic dehydration and blanching on the material quality were investigated. The main aim of the studies was to find a drying mode by which the product quality degradation is minimized. Therefore, except for drying kinetics, the total color change, water activity, retention of betanin, and ability to rehydration were examined. It was proved that drying of beetroots in intermittent conditions contributes to shorter drying time, higher retention of betanin, better color preservation, and less water activity.