Abstract

Extra virgin olive oil (EVOO) and canola oil (CO) quality and composition variations with temperature are tested using UV-Vis absorption and fluorescence spectroscopy. The amplitudes of the absorbance and fluorescence signals gradually decreased as the temperature rose, indicating a change in the molecular structures of both types of oils. About the entire spectrum of pheophytin-a, b, carotenoids, lutein, and vitamin E in EVOO and linoleic acid and oleic acid in CO vanished at about 200°C, which was a considerable change. In a separate experiment, the transmission values for EVOO and CO were determined to be 33% and 75%, respectively, and it was shown that the output of the laser fluctuations in petroleum at a constant level (i.e., ambient) are linear depending on the intake. However, a nonlinear behaviour was seen in the transmission through heated oil, indicating a molecule optical response to temperature variations. The impact of oil adulteration and storage time were also assessed.