studied stepwise varying drying condition on banana pieces in two stage heat pump drier and observed that time-varying drying air temperature in batch drying of banana slices had a favorable impact on drying kinetics as well as the color of the dried products. They observed that color degradation was reduced by 40% and 23% for step-up and step-down mode of drying respectively in the temperature range between 20 C and 35 C. A significant difference in the overall color change of the banana samples dried under step-wise temperature variation when compared with samples under constant temperature drying was reported