MODELING WITH SHRINKAGE DURING THE VACUUM DRYING OF CARROT (DAUCUS CAROTA)

Abstract

ABSTRACT The drying kinetics of carrot slices have been measured in a vacuum chamber, the experiments were carried out at various temperatures (50, 60 and 70C) under conditions of low pressures (5, 15 and 25 kPa). It was observed that the best values of diffusivity were obtained at the major temperature and low pressure for the samples pretreated by freezing. The experimental data were modeled using Fick's diffusional model in terms of moisture concentration with and without shrinkage. It is found that the calculated values of effective diffusivity for the drying process considering no shrinkage were greater than those for the drying process considering shrinkage. PRACTICAL APPLICATIONS Vacuum drying is the effective method of removal of moisture from fruits and vegetables. In this research, the experimental study and modeling on drying kinetics during the vacuum drying of carrot was studied. Also, the effect of the pretreatments, pressure and temperature on the vacuum drying kinetics was determined. A diffusion model based on Fick's second law of diffusion with and without shrinkage was used to describe the transport mechanism in the falling drying rate regions. The results from this research can be used asreference for vacuum drying and modeling kinetics drying of carrot and vegetables.