3.2. Rehydration kineticsThe water

3.2. Rehydration kinetics
The water intake curves for instant rice under different dry conditions, showing weight gain on rehydration (WGR) as a function of rehydration time, are shown in Fig. 2. In all the cases the amount of moisture absorbed increases with rehydration time, but at a decreasing rate up to an asymptotic value. The rehydration stabilised ranged from 3 min (for MW = 560 W, T = 70◦C) to 15 min (for MW = 0 W, T = 90◦C) and WGR was around 2.5 under various drying conditions. These curves followed a general pattern of bounded growth, characteristic of a first order process. Therefore an asymptotic model(Eq. (13)) with non-zero asymptote was chosen to describe the kinetics of rehydration, where the subscript e refers to equilibrium time: