Development, validation and application of an UFLC-DAD-ESI-MS method for determination of carbonyl compounds in soybean oil during continuous heating

- Edible oils play an important role in human nutrition.
- A method was developed for analyzing carbonyl compounds in heated soybean oil.
- It has presented good selectivity and precision, as well as sensibility and accuracy.
- Ten CC identified, including 4-hydroxy-2-nonenal, 4-hydroxy-2-hexenal and acrolein.
- The average concentrations for the CC ranged from 2.2 to 36.9 μg.g−1 of oil.

A method was developed for the extraction and UFLC-DAD-ESI-MS analysis of carbonyl compounds (CCs) in oils heated to 180 °C. Different parameters were evaluated, and the best results were 1.5 ml of acetonitrile as the extraction solvent, manual stirring for 3 min and 30 min of sonication time. The method was validated using soybean oil samples spiked with CCs at concentration levels ranging from 0.2 to 10.0 μg.mL−1. The average recoveries in the lowest concentration level ranged from 70.7% to 85.0%. Detection limits ranged from 0.03 to 0.1 μg.mL−1, and the quantification limit was 0.2 μg.mL−1 for all compounds. When the method was applied to samples of heated oil, the CCs identified were 4-hydroxy-2-nonenal, 2,4-decadienal, 2,4-heptadienal, 4-hydroxy -2-hexenal, acrolein, 2-heptenal, 2-octenal, 4,5-epoxy-2-decadal, 2-decenal, and 2-undecenal, with the first three mentioned presenting the highest mean concentrations after heating, specifically 36.9, 34.8 and 22.6 μg.g−1 of oil, respectively.