Determination of 2,4‐decadienal in edible oils using reversed‐phase liquid chromatography and its application as an alternative indicator of lipid oxidation

Abstract As a major product of linoleic acid‐rich oils, 2,4‐decadienal has unique reactivity that may be potentially toxic to human body. In this study, a reliable reversed‐phase liquid chromatography method for the determination of carbonyls was developed, and 2,4‐decadienal as the target aldehyde was validated. Furthermore, the possibility of 2,4‐decadienal as a lipid oxidation marker was evaluated. The optimal sample pretreatment method was extraction by 2 mL of acetonitrile three times, followed by derivatization at 40 °C for 30 min. The method was linear, sensitive, and accurate with detection and quantification limits of 15 and 50 nmol/L, respectively, and had good average recoveries for 2,4‐decadienal in oil samples. In tested edible oils, during heating at 180 °C, the level of 2,4‐decadienal rose faster than other aldehydes, including one of the characteristic aldehydes, hexanal. Moreover, good linear relationships between the 2,4‐decadienal content and other oxidation indices ( R 2 = 0.858 to 0.984 for the anisidine value; R 2 = 0.876 to 0.986 for the total oxidation value) were observed in sunflower and corn oils under 8 hr heating at three temperatures (120, 150, and 180 °C), indicating that 2,4‐decadienal can predict the oxidation of oil. Practical Application 2,4‐Decadienal is a toxic aldehyde produced by the oxidation of linoleic acid‐rich oils, which is closely related to human health. This work is the first to demonstrate that 2,4‐decadienal can be used as an alternative oxidation indicator for linoleic acid‐rich oils and is of great significance for the quality control of edible oil in the food industry.