Effects of Drying Conditions on Rehydration Characteristics of Tobacco Strips

In order to find out the interaction among different heating and moistening processes,the effects of temperature and humidity of drying medium and initial moisture content in tobacco strips on the rehydration characteristics of strips were investigated by simulating the conditions of strips drying and rehydrating in a climate chamber.The results showed that: 1) Dualistic Weibull distribution model could be used to describe the kinetics of strips drying,and the parameter,α,in Weibull model could be used as a characteristic time parameter to characterize the rate of a drying process.2) At lower drying temperature(70,80℃),the rehydration rate decreased significantly with the increase of humidity of drying medium;while at higher drying temperature(90℃),the humidity of drying medium affected strips' rehydration rate relatively slightly.Equilibrium moisture content of rehydration decreased with the increase of humidity of drying medium,and there was no obvious difference between the equilibrium moisture content and drying temperature.3) At the same drying condition,strips' rehydration rate increased with the decrease of moisture content in dried strips.When the initial moisture content in strips reduced from 14% to 5%,the equilibrium moisture content during rehydration increased first and then decreased,while it decreased more obviously when the initial moisture content lowered to 5%.