Evaluation the convective drying of apple slices: Investigation of temperature changes by infrared thermography

One of the important aspects of food drying technology is studying the moisture and temperature changes during the drying process. The temperature changes of the sample are often evaluated by instruments such as thermocouples and thermometers. In this research, infrared thermography was implemented for evaluating the temperature changes during drying process. Experiments were performed for drying air temperature of 60 and 80 oC and temperature changes were measured with T-type thermocouples and infrared thermography. Also, moisture content of apple slice was measured during dying process. The result shows infrared thermography is a good instrument for recording the temperature changes without contact or destroying sample. evaluation drying curves shows, with increasing drying air temperature, heat and mass transfer process increase and drying times decreased consequently.