3.2. Drying Behavior of Carrot
Experiments were conducted to determine the effects of pre-treatments and drying methods on dehydration and rehydration properties of carrot using a mechanical dryer and a solar dryer. The temperature of the mechanical dryer was 60°C, while the temperature in the solar dryer fluctuated from 30ºC to 60°C. This fluctuation was due to black body inside the drier which was covered by polyethylene and the intensity of sun light. Carrot slices were dried in the mechanical dryer (at 60ºC, at constant loading density, 0.75 lb/ft2) and in the solar dryer (at 30-60ºC, at loading density 0.75 lb/ft2 ) using single layer. The experimental data were analyzed by as per the Fick’s 2nd law of diffusion and moisture ratio (MR) versus drying time (min) were plotted on a semi-log co-ordinate and regression lines and equations were obtained (Figure 1(a) and Figure 1(b)and equations 1 to 8)).