Synthesis and Occurrence of Oxoaldehydes in Used Frying Oils

Article abstract of DOI:10.1021/jf00049a006

As part of our efforts to identify volatile decomposition products in used frying oils, a series of 4- and 5-oxoaldehydes were synthesized, purified, and characterized by gas chromatography, gas chromatography-mass spectrometry, gas-chromatography-Fourier transform infrared spectrometry, and nuclear magnetic resonance spectrometry.Oxoaldehydes have been proposed as possible precursors of alkylfurans, which have potential anticancer effects.In a model reaction 4-oxononanal was refluxed in hexane for 40 days and only trace amounts of 2-pentylfuran were produced, suggesting that it is not a major precursor of the furan.The volatile constituents of used frying oils obtained from commercial food processors were studied, and 4-oxohexanal, 4-oxooctanal, 4-oxononanal, and 4-oxodecanal were identified.Keywords: Oxoaldehydes; odor threshold; frying oil