Different drying methods for plum fruits were compared in this case study. Samples were dried at a temperature of 70°C using the method of hot air drying as well using hybrid solar drying at three levels of air velocity (0.5, 1, and 2 m/s) and open sun drying. The dried samples were then compared on the basis of changes in colour, shrinkage and rehydration. The effect of air velocity on colour change was significant (P < 0.05) at the three different levels (0.5, 1, and 2 m/s), whereas effects on shrinkage and rehydration ratio were not significant (P < 0.05). The best conditions for plum drying with respect to values of colour change, shrinkage, rehydration ratio and the drying costs were obtained for the plums dried using a hybrid solar dryer at an air velocity of 1 m/s.
