Four mathematical models for thin layer drying were selected to simulate the drying characteristics of sliced and solid turmeric. Moisture content data were converted to MR and fitted to these four equations. The values of estimated parameters of the equations were listed (Table 1). Among the stated models, the Page model gave highest value of R2 (0.9946) with low value of SEE (0.0317) for sliced samples in comparison to solid.
This indicates that, sliced turmeric drying fits better to Page model. This in turn established good drying behavior of turmeric in sliced form than whole. Nevertheless, the SCD system exhibited satisfactory performance for turmeric drying as evident from R2 and SEE values obtained irrespective of it being whole or sliced.
Thus, to understand the drying behavior, the predicted values of MR from the Page model for sliced and solid turmeric were fitted with respective experimental values against time and represented in Fig. 9 and Fig. 10, respectively. While drying whole turmeric, it was observed that at the initial stage, the predicted values differ significantly from the experimented values. Whereas, during drying of sliced turmeric, predicted moisture ratios were in good agreement with the experimented values. This observation again conforms to the higher effective moisture diffusivity behavior exhibited by sliced turmeric (1.852 · 1010 m2 s1) compared to its whole form (1.456 · 1010 m2 s1) during the initial period of drying