Drying characteristics and heat energy requirement of cornelian cherry fruits (Cornus mas L.)

Abstract

In this research, drying characteristics and energy requirement for drying of cornelian cherry fruits (Cornus mas L.) were reported. Cornelian cherry fruits were dehydrated in a parallel air flow type dryer. The dryer mainly consisted of an electric heater, adjustable forward curved centrifugal fan, corrosion resistant plastic mesh, corrosion resistant metal sheet, sytrafor insulator, drying air inlet and outlet channels as well as thermostat, temperature indicators and wattmeter. Freshly harvested cornelian cherry fruits were dried at 50, 60 and 70 degrees C temperatures. Selected drying air velocities were 0.3, 0.6 and 0.9 m/s for each temperature. Cornelian cherry fruits were dehydrated from the initial moisture content of 233% (percentage dry basis) to a final moisture content of 8%. During experiments, drying product collected from the plastic mesh were also weighted to note amount of water evaporated. The results showed that drying air temperature significantly influenced the total drying time and air velocity also influenced the total energy requirement for drying. On the contrary, the effect of the drying air velocity on the total drying time was found less. The minimum and the maximum energy requirement for drying of cornelian cherry fruits were also determined as 11.57 kW h/kg and 39.55 kW h/kg for 70 degrees C, 0.3 m/s and 50 degrees C, 0.9 m/s, respectively. As a result, to reduce drying energy consumption, it can be recommended that the drying air velocity must not be more than 0.3 m/s for all different temperatures and the most ideal temperature was found 70 degrees C for this application. (c) 2005 Elsevier Ltd. All rights reserved.