Application of Mass Transfer Regime Approach Theory to Drying of Carrot

Abstract

The understanding of the drying of food materials is based on the theoretical, empirical, and semi-empirical models. The fundamental understanding of the drying process is always been a nebulous concept. These models merely provide information based on the fitting of experimental data and fail to explain the actual physics involved during the drying operation. Mass transfer regime approach for drying, developed in the previous year is still a nascent idea but a vital tool to analyze a drying operation. The paper discusses the application of the mass transfer regime approach to the drying of carrots. Drying operation involves internal diffusion of moisture from the material core to the surface followed by the external mass transfer to the environment. The mass transfer regime approach is used to represent the rate of these steps in the form of equations analogous to the heterogeneous reaction. A comparison of these equations with the experimental rate is made to determine the governing step (internal or external) during the drying process. It was observed that during drying, there is a transition between these governing steps owing to the dynamics of the material and external environment. This approach will thus provide more information on the drying operation and help to design the drying process.