Emissivity determination of oil palm fresh fruit ripeness using a thermal imaging technique
Thermal imaging is a technique to transform the invisible radiation pattern of an object into visible images for feature extraction and analysis. Infrared thermal imaging has a wide application in several fields such as engineering, aerospace, agriculture, civil, medicine, and veterinary. Emissivity is one of the important parameters used to determine the surface temperature of agricultural products and also to manage some agricultural engineering procedures. The purpose of this paper is to determine total emissivity as an essential parameter of non-destructive thermometry for oil palm fresh fruit bunches in different stage of ripeness (hard bunch, under-ripe, ripe, over-ripe and rotten bunch). Moreover, in this research, the influence of surface temperature of oil palm fresh fruit bunches on the ripeness was investigated whereby the fresh fruit bunches were heated to 100°C. Then, a thermal imaging camera and contact thermometer were used to determine the surface temperature of the bunches. The results show that emissivity of hard bunches is 94%, the emissivity of under-ripe, ripe and over-ripe is 95%, and the emissivity of rotten bunches is 98%. At these percentages, the thermal camera and contact thermometer demonstrate the same temperature.
Zolfagharnassab, S., Mohamed Shariff, A.R. and Ehsani, R. 2017. Emissivity determination of oil palm fresh fruit ripeness using a thermal imaging technique. Acta Hort. (ISHS) 1152:189-194
oil palm, thermal imaging, emissivity, ripeness, FLIR, infrared