Effect of temperature on water diffusion during rehydration of sun-dried red pepper (Capsicum annuum L.)

Abstract

Rehydration, which is a complex process aimed at the restoration of raw material properties when dried material comes in contact with water. In the present research, studies were conducted to probe the kinetics of rehydration of sun-dried red peppers. The kinetics associated with rehydrating sun-dried red peppers was studied at three different temperatures (25, 35 and 45 °C). To describe the rehydration kinetics, four different models, Peleg’s, Weibull, first order and exponential association, were considered. Between these four models proposed Weibull model gave a better fit for all rehydration conditions applied. The effective moisture diffusivity values of red peppers increased as water rehydration temperature increased. The values of the effective moisture diffusivity of red peppers were in the range 1.37 × 10−9–1.48 × 10−9 m2 s−1. On the other hand, the activation energy for rehydration kinetic was also calculated using Arrhenius equation and found as 3.17 kJ mol−1.