Semi-Empirical Mathematical Modeling, Energy and Exergy Analysis, and Textural Characteristics of Convectively Dried Plantain Banana Slices

Thin-layer convective drying of plantain banana was performed at four different temperatures from 50 to 80 degrees C, with slice thicknesses from 2 to 8 mm. The drying curves, fitted to seven different semi-empirical mathematical models, were successfully used to fit experimental data (R-2 0.72-0.99). The diffusion approach had better applicability in envisaging the moisture ratio at any time during the drying process, with the maximum correlation value (R-2 0.99) and minimum value of x(2) (2.5x10(-5) to 1.5x10(-4)) and RMSE (5.0 x10(-3) to 1.2x10(-2)). The Deff, hm, and Ea values were calculated on the basis of the experimental data, and overall ranged from 1.11x10(-10) to 1.79x10(-9) m(2) s(-1), 3.17x10(-8) to 2.20 x10(-7) m s(-1) and 13.70 to 18.23 kJ mol(-1), respectively. The process energy consumption varied from 23.3 to 121.4 kWh kg(-1). The correlation study showed that the drying temperature had a close correlation with hm value and sample hardness. A significant (p < 0.05) increase in hardness of dried plantain banana was observed at 80 degrees C compared to the other temperatures. Additionally, the sample hardness and process energy consumption were more positively correlated with the thickness of the samples.