Development of Mini Solar Tunnel Dryer and Validation of Thin Layer Drying Models for Pomegranate Seeds

A portable MSTD (mini solar tunnel dryer) was developed and evaluated in terms of drying rate, MR (moisture ratio) and drying efficiency for drying of pomegranate seeds. The drying characteristic curves were also determined for drying in MSTD and OSD (open sun drying). In order to study the drying behaviour of pomegranate seeds in OSD and MSTD, seven different models were fitted. The best prediction model was determined to estimate drying kinetics as criteria for evaluating the goodness-of-fit based on R2, SSE and RMSE. The Approximation of Diffusion model was adequate to describe the drying kinetics of pomegranate seeds in OSD and MSTD with R2 value of 0.99189 and 0.9943, respectively. The MSTD was 7% more efficient in drying of pomegranate seeds compared to OSD without affecting the quality of seeds. The dryer can be used by the farmers as an alternative to sun drying for on field drying of their product without compromising the quality.