Performance Evaluation of aSolar Dryer for Sapota Drying

Abstract

The performance of natural convection solar dryer was evaluated for sapota drying at 1 kg/m2 area and compared with open sun drying. Sapota was sliced in 5mm pieces and dipped in 1% potassium meta-bisulphate for 10 minutes to retain its color. The results indicated that the moisture reduced from 78 % (w.b) to 7.9% (w.b) and the drying time for 1kg loading rates was observed to be as 23 h for solar drying and 35 h for open sun drying. The relationships between various drying parameters were studied. The total sugar of fresh fruit was increased from 18% to 32.10% solar dried fruit and 30.17% in open sun dried fruit, whereas the protein content of fresh sapota was reduced from 10.25% in fresh fruits to 8.68% and 6.55% in solar dried and the open sun dried fruit respectively.