Correlation of fatty acids, glyceride core aldehydes, and polycyclic aromatic hydrocarbons during the thermal oxidation of hazelnut oil

Fatty acids in edible oil will be oxidized into aldehydes and ketones during hot processing, which will produce polycyclic aromatic hydrocarbons (PAHs) and other harmful substances to human health. Hazelnut oil was heated under different temperatures and times. For each type of oil sample, fatty acid composition, glyceride core aldehyde (GCAs), and PAHs were investigated. The correlation between these indicators was analyzed by the Pearson correlation coefficient. As the main component of hazelnut oil, oleic acid plays an essential role in the formation of GCAs. For GCAs, 9-oxo and 10-oxo-8 compounds were detected. The content of 9-oxo increased with the temperature, while there was no significant change in 10-oxo-8. There exist 15 kinds of PAHs in hazelnut oil. Correlation result shows that GCAs were strongly correlated with six kinds of PAHs (BaA, CHR, BbF, PYR, BaP, and IPY), which shows that GCAs are the precursor of several kinds of PAHs. The research provides strong theoretical guidance for the edible safety and control methods of hazelnut oil.