Investigation on drying kinetics analysis of gooseberry slices dried under open sun

Abstract

An experimental analysis of the drying behaviour of gooseberry slices dried in the open sun is described in this article. Gooseberries brought from the local market were cut approximately semi-circular in cross-section, with an average length of 20–25 mm and a thickness of 3–5 mm. Using the hot air dryer method, the moisture content (MC) of gooseberry slices in their initial condition was estimated to be 87.81% wet-basis. The drying data revealed a steady reduction in MC with time, indicating the lack of a consistent rate drying phase. To fit the drying data, ten mathematical models were used. The selected models were analysed using a multi-regression methodology in an Excel-solver equation. The optimal drying model was chosen based on the values of the coefficient of determination (R2), reduced chi-square (χ2) and root mean square error (RMSE). The logarithmic model was chosen as the best drying model for open sun drying of gooseberry slices as it had the highest R2 (0.99758980) and the lowest values of χ2 (0.00017191) and RMSE (0.01255328) of all the models tested. Multi-regression analysis resulted in the development of a thin layer drying equation that can be used to forecast moisture ratio (MR) at a specific drying period. The estimated value of effective diffusivity was found to be within its value for various agro-products.

Keywords

• Drying kinetics
• Drying rate
• Moisture content
• Moisture ratio
• Effective diffusivity