Simultaneous Determination of 13-HODE, 9,10-DHODE, and 9,10,13-THODE in Cured Meat Products by LC-MS/MS

A method was developed for simultaneous determination of 13-hydroxyoctadecadienoic acid (13-HODE), 9,10-dihydroxyoctadecenoic acid (9,10-DHODE), and 9,10,13-trihydroxyoctadecenoic acid (9,10,13-THODE) in cured meat products. The analytes, extracted with methanol and cleaned by solid phase extraction, were separated on an XBridge C18 column (150*4.6 mm, 5 μm) with a mobile phase consisting of 0.1 % formic acid in water and acetonitrile, followed by detection with an electrospray ionization tandem mass spectrometry in negative-ion mode. The proposed method produced satisfactory reliability, sensitivity, and accuracy. Recoveries of the three analytes within the spiking range of 0.5–40 μg/g were 80.0–97.8 %, and limits of quantification of 13-HODE, 9,10-DHODE, and 9,10,13-THODE were 0.4, 0.025, and 0.05 μg/g, respectively. The method was successfully employed to detect the three fatty acids with hydroxyl(s) in cured meat products. It was shown that all samples contained the three analytes simultaneously, with concentrations ranging 1.40–100.77 μg/g for 13-HODE, 0.13–1.82 μg/g for 9,10-DHODE, and 0.49–10.12 μg/g for 9,10,13-THODE, respectively. The analytical result also indicated there were isomers of analytes, and the real content of fatty acids with hydroxyl(s) from oxidation of LA might be much higher.