Drying Kinetics of Custard Apple Pulp in Natural Circulation Solar Dryer

Abstract

Custard apple (Annona squamosa) is popularly called as sitaphal belonging to Annonaceae family. In the investigation custard apple pulp was dried in natural circulation solar dryer andevaluated drying characteristics of custard apple pulp viz., drying rates, moisture diffusivity. The drying data of custard apple pulp was used to calculate the effective diffusion coefficients by the equation of Fick's law of diffusion. Also it was fitted to study the various models. The moisture diffusivity of custard apple pulp was found 9.12816 x 10-7 m²/s. Among the all four models studied, the logarithmic model was found most satisfactory to represent the drying of custard apple pulp.