Mass Transfer Parameters and Modeling of Hot Air Drying Kinetics of Dill Leaves

Abstract

Abstract Moisture diffusivity (D em ), mass transfer coefficient (h m ), activation energy and drying kinetics of the dill leaves were studied and modeled as a function of temperature (40–70 °C) and moisture content (0.20–5.67 kg water/kg dry matter). Results showed that the D em and h m significantly depend on the temperature and moisture content ( p < 0.05). The average of D em and h m varied between 4.02 × 10 –9 to 9.65 × 10 –9 m 2 /s, and 2.38 × 10 –7 to 6.33 × 10 –7 m/s, respectively. Activation energy showed a significant dependence on the moisture content and estimated as 16.84 kJ/mol for diffusion model and 28.70 kJ/mol for mass transfer model. Out of the six models considered, the logarithmic model showed the best fit to drying behavior of the dill leaves.