An improved method for the measurement of 3-monochloropropanediol esters by matrix solid-phase dispersion supported liquid–liquid extraction

Summary 3-Monochloropropanediol (3-MCPD) esters are contaminants produced from the high-temperature processing of edible oils. The accurate measurement of 3-MCPD using an easy-to-follow and reliable method that uses a readily available instrument is important. Here, we report an acid transesterification heptafluorobutyrylimidazole (HFBI) derivatisation method for the accurate measurement of 3-MCPD esters in edible oils. We developed a dispersed matrix solid-phase supported liquid–liquid extraction (DMSP-SLE) system to remove impurities. Both the transesterification and DMSP-SLE conditions were optimised. A good linear relationship was obtained within the range of 0.05–10 mg kg−1 (R2 ≥ 0.999) in both blank solvent and an oil sample. The limit of detection was 20.36 μg kg−1. The average recovery of the 3-MCPD esters spiked at 0.5, 1.0 and 2.0 mg kg−1 into a blank oil matrix was in a range from 105.09 ± 2.77% to 120.16 ± 10.88%. The method we developed was further confirmed by performing detection on a Food Analysis Performance Assessment Scheme (FAPAS) sample.