Drying and Rehydrating Kinetics of Green and Red Peppers

The effects of air temperature, air velocity, and pretreatments (blanching, sulphiting, and sodium chloride dipping) on drying kinetics of green‐ and red‐pepper slices were investigated. Drying experiments were performed in a fluidized bed dryer. In the falling rate period, moisture transfer from peppers was described by applying the unsteady state Fickian diffusion model, and the apparent moisture diffusion coefficients (D a ) were calculated. The effect of temperature on D a could be interpreted according to Arrhenius law. Drying rate and therefore D a values were found to be affected by pretreatments. Rehydration rates of dried peppers at 25 and 45 °C were also determined and found to be independent of drying conditions and rehydration temperature. Predrying treatments were found to improve partly the rehydration characteristics of peppers.