Thermal Degradation of Vegetable Oils: Spectroscopic Measurement and Analysis

The paper deals with measuring of structural changes in edible oils during their heating giving arise to unsafe degradation products. The attention is paid to the major decomposition product of heated oxidized linoleate and content of carotenoids with antioxidant effects. Analysis is based on Raman spectral data that provide unique information about the structure of the oils. Raman spectroscopy offers effective and rapid way for oils quality control with respect to their health benefits and in terms of processes in food technology. Three most common vegetable oils were used for the thermal degradation study: sunflower, canola and olive oil. Measured were both, extra virgin and refined oils. Mathematically processed spectral data indicate the least action of thermal load for olive oils. Then due to a significant content of antioxidants it is canola oil. The worst effect in terms of thermal decomposition products formation and the loss of cis double bonds arise for sunflower oils.