EFFECT OF DRYING TIME AND SLICE THICKNESS ON SOLAR DRYING OF CARROT

Abstract

This study focused on the effect of drying time and slices thickness on solar drying of carrot. Carrot is harvested in abundance during its season in most developing countries. However storage for period of scarcity and conversion to other products are not common hence heavy losses are incurred leading to economic losses as well as environmental pollution. Dried carrot is currently being embraced in most developing countries. Drying characteristics of carrot as affected by drying time and slice thickness were therefore studied with a view to understanding the drying kinetics and provide information useful in dryer design. Fresh carrots were dried with different diameters and different slice thickness in solar dryer and direct sun drying in Agricultural and Environmental Engineering Department Obakekere Federal University of Technology Akure. The control parameters considered were the carrot slices thickness (4,6,8,10,12)mm, diameter (18, 22,26 and 30)mm and initial mass 50g for each diameter by thickness of carrot slices while the operating parameters determined were change in weight, moisture content and drying rate. From the experiment, the lower the thickness the more rapid moisture will be removed from the product, the reduction in the drying rate of higher thickness is as a result of movement of moisture from the core of the slice to the surface before evaporation. Diameter does not really have any effect on drying of carrot but thickness must be put into consideration in drying, the higher the thickness the longer the time it will take to dry up and reach reasonable drying moisture content