This study reinvestigated acrolein generation pathways from linoleic acid (LA) and linolenic acid (LnA) focusing on singlet oxygen (¹O₂) oxidation (type II photo-oxidation). Standards of major fatty acid hydroperoxide (FAOOH) isomers were prepared and analyzed. ¹O₂ oxidation products of LA and LnA, but not oleic acid (OA), were significant acrolein sources. Acrolein formation from LA-rich oils increased with photo irradiation. ¹O₂ oxidation-specific HpOTE isomers (10- and 15-HpOTE) yielded twice the acrolein compared to other HpOTE isomers. This study provides a new acrolein formation pathway from type II photo-oxidation, informing oil storage and processing to reduce acrolein exposure.
