Evaluation of thin layer drying kinetics of taro root (Colocasia esculenta L.)
Keywords:Drying kinetics, taro roots, thin layer drying, effective moisture diffusivity, activation energy.
Appropriate drying model is an important attribute for describing the drying kinetics of food products. Thin layer drying of taro roots were performed in a laboratory scale hot air dryer operated at 50oC, 60oC and 70oC temperature with air velocity of 0.5 ms-1. Analysis of the result exhibits that drying of taro roots took place in falling rate period. Thin layer model such as Henderson-Pabis, Page and Lewis equation were studied to fit with the experimental data using nonlinear regression analysis. The suitable drying model was selected based on chi square (χ2), root mean square error and relative percent error. Study of goodness of fit indicated that among the proposed model, Page equation gave better fit than all drying conditions used. Effective moisture diffusivity was determined through simplified Fick’s second law of diffusion. Activation energy for moisture removal was described by Arrhenius equation and found 18.01kjmol-1 for present study.