Mechanisms of the Formation of Nonvolatile and Volatile Oxidation Products from Methyl Linoleic Acid at High Temperatures

Abstract

The impact of the oxidation of linoleic acid cannot be overlooked in daily food consumption. This study used gas chromatography−mass spectrometry (GC-MS) to identify both nonvolatile oxidation products and volatile oxidation products of methyl linoleic acid at 180 °C and density function theory to investigate oxidation mechanisms. An analysis of nonvolatile oxidation products revealed the presence of three primary oxidation products. The three primary oxidation products were identified as hydroperoxides, peroxide-linked dimers, and heterocyclic compounds in a ratio of 2.70:1:3.69 (mmol/mmol/mmol). The volatile components of secondary oxidation products were found including aldehydes (40.77%), alkanes (19.89%), alcohols (9.02%), furans (6.11%), epoxides (0.46%), and acids (2.50%). DFT calculation proved that the secondary oxidation products mainly came from peroxides (77%). Finally, we look forward to our research contributing positively to lipid autoxidation and human health.

Kinetics of Squalene Quenching Singlet Oxygen and the Thermal Degradation Products Identification

“…In this experiment, theoretical calculations were performed using the Gaussian 09W computational chemistry software (Gaussian, Inc.) based on our previous methods . The geometric structure DFT calculations were carried out using the B3LYP/6-31G method to optimize the geometric structure and activation energies.…”