Mathematical models to describe the drying process of Moringa oleifera leaves in a convective-air dryer
Document Type
Article
Publication Date
1-1-2021
Abstract
Drying kinetics of Malaysian Moringa oleifera leaves was investigated using a convective-air dryer. The drying parameters were: temperature (40, 50, 60, 70 degrees C), air velocity (1.3 m s-1, 1.7 m s-1). The drying process took place in the falling rate period and there was an absence of a constant rate period in this experiment. Six mathematical models (Lewis, Henderson and Pabis, Wang and Singh, Peleg, Page, and logarithmic) were selected for the description of drying characteristics of the leaves. The Wang and Singh model was determined as the best model based on the highest overall coefficient determinant (R2) and the lowest overall root mean square error (RMSE). The effective diffusivity (Deg ) was also calculated which was in the range of 3.98 x 10-11 m2 s-1 to 1.74 x 10-10 m2 s-1. An Arrhenius relation was constructed to determine the activation energy for the samples in the convective air dryer. The activation energy for M. oleifera leaves was 39.82 kJ mol-1 and 33.13 kJ mol-1 at drying velocities of 1.3 m s-1 and 1.7 m s-1, respectively.
Keywords
Drying kinetics, Convective-air drying, Mathematical modelling, Effective diffusivity, Activation energy
Divisions
Science
Publication Title
Czech Journal of Food Sciences
Volume
39
Issue
No. 6