Evaluation of Oxidative Phenomena of an Olive Oil Model System After Application of Cold Atmospheric Plasma Treatment

The effect of cold atmospheric plasma (CAP) (a pin-to-liquid DBD) (28–32 kV, 1–10 min) on virgin olive oil (VOO) lipid oxidation was kinetically investigated. Quality assessment was performed (bioactive compound concentrations and fatty acid profiles) while the samples were further characterized by Fourier Transform Infrared (FTIR) spectroscopy and proton Nuclear Magnetic Resonance (1H NMR). Intense processing (>5 min and voltages > 31 kV) significantly affected the quality of VOO, enhancing the oxidative reactions. CAP treatment led to an eight-fold increase in peroxide values and to a decrease in total antioxidants by up to 80% compared to untreated VOO. Carbonyl compounds (aldehydes, carboxylic acids) and hydroperoxide intermediates were the main oxidation products, while polyunsaturated fatty acids (PUFAs) dropped from 81.17% to 76.51%. The double bonds in the acyl chains were also highly reactive and facilitate the oxidation and subsequent fragmentation of the VOO.