Experimental characterization and thin-layer convective drying modeling of Jamun (Indian Blackberry) slices

In this research paper, thin-layer convective drying characteristics for Jamun (Indian Blackberry) slices were analyzed at 50 to 80 degrees C air drying temperatures with an interval of 10 degrees C and an air velocity of 0.5 m/s. During the drying investigation, it was found that it occurred only in a range of falling periods of drying. With drying air temperature increment, the duration of drying was significantly reduced. Moisture removal took place from initially at 83.68 (% wb) to finally around 2.88 (% wb) in the tray dryer. The experimental observations were verified with various drying models of thin-layer. By nonlinear regression analysis, the selected drying model parameters were determined. Between the experimental and estimated moisture ratios, the selected drying models were examined with the help of r-squared (r(2)), Mean Absolute Percentage Error (MAPE), Chi-square (chi(2)) and Root Mean Squared Deviations (RMSD). As a result, it was found that the Page model was fitted satisfactorily at 50 and 60 degrees C air drying temperatures while the model developed by Midilli et al was fitted satisfactorily at 70 and 80 degrees C air drying temperatures to characterize Jamun slices with convective drying curves. The effective diffusion of water and activation energy values were estimated as 2.79-7.71x10(-9 )m(2)/min and 30.82 kJ/mol respectively for Jamun slices.