The autooxidation process in linoleic acid screened by Raman spectroscopy

The chemical changes associated to the autooxidation process of linoleic acid (LA) were detected by Raman spectroscopy and interpreted in the light of density functional theory (DFT) calculations performed for both the fatty acid and its main oxidation products. The present methodology, applied for a six‐day period upon induction of oxidation (through heating), allowed to understand the chemical modifications occurring during the oxidation process. Raman spectroscopy was shown to be a suitable and reliable technique for assessing the oxidation degree of fatty acid samples, particularly pure fatty acids, mainly when computational methods are used alongside to predict the spectral features of the distinct chemical entities involved. Screening of the oxidation process was mostly based on the loss of intensity of the bands assigned to LA cis‐double bonds. Copyright © 2012 John Wiley & Sons, Ltd. The chemical changes associated to the autooxidation process of LA were detected by Raman spectroscopy and interpreted in the light of DFT calculations. The success of Raman spectroscopy in probing the oxidation state of a fatty acid, coupled to a simpler setup and virtually no sample preparation, renders this technique a very useful and promising tool, namely for assessing the quality of edible oils and other lipid‐containing food products in situ.