Determination of oxidative deterioration in edible oils by high-pressure photoionization time-of-flight mass spectrometry

[Display omitted] •HPPI-TOFMS was introduced for rapid evaluation of oxidative deterioration in edible oils via effective detection of their VOCs fingerprints change under thermal-oxidation or photo-oxidation.•For the first time, non-targeted discrimination of oxidized oils into various oxidation degrees was realized by coupling HPPI-TOFMS with OPLS-DA.•Nonanal in extra virgin olive oils, 2-pentylfuran in peanut oils, trans-2-heptenal in sunflower oils and trans–trans-2, 4-heptadienal in corn oils were selected as potential oxidation indicators. Since lipid oxidation often causes serious food safety issues worldwide, determination of oil’s oxidative deterioration becomes quite significant, which still calls for efficient analytical methods. In this work, high-pressure photoionization time-of-flight mass spectrometry (HPPI-TOFMS) was firstly introduced for rapid detection of oxidative deterioration in edible oils. Through non-targeted qualitative analysis, oxidized oils with various oxidation levels were successfully discriminated for the first time by coupling HPPI-TOFMS with the orthogonal partial least squares discriminant analysis (OPLS-DA). Furthermore, by targeted interpretation of the HPPI-TOFMS mass spectra and the subsequent regression analysis (signal intensities vs TOTOX values), good linear correlations were observed for several predominant VOCs. Those specific VOCs were promising oxidation indicators, which would play important roles as TOTOX to judge the oxidation states of tested samples. The proposed HPPI-TOFMS methodology can be used as an innovative tool for accurate and effective assessment of lipid oxidation in edible oils.