Effect of pre-treatments on drying and rehydration characteristics of Amla (Phyllanthus emblica L.) under direct solar radiation

Abstract

This study investigates the effect of various pre-treatments on the drying and rehydration characteristics of Amla (Phyllanthus emblica L.) under open sun drying. Five treatments were studied: untreated (control), flaking, pricking, pricking with blanching, and pricking with blanching and flaking. Moisture reduction during drying and rehydration behavior were assessed. Results showed that untreated Amla required approximately 8 days to dry, while pricking reduced drying time to 42 h. Combining pricking with blanching further reduced the drying time to 29 h, while flaking alone limited drying to 12 h. The highest rehydration ratio (3.14) and coefficient of restoration (0.558) were observed for flaked samples. These findings suggest that appropriate pre-treatments can significantly improve drying efficiency and rehydration quality of Amla, thereby enhancing its potential as a value-added dried product.