Abstract
For clarification of the effects of the triacylglycerol (TG) structure on volatile components produced during the autoxidation of highly unsaturated fatty acids, TG samples containing eicosapentaenoic acid (EPA) and palmitic acid (1 : 2) were autoxidized at 25°C and headspace volatiles were analyzed by gas liquid chromatography using solid phase micro-extraction method.
Hydroperoxides were produced much more during this autoxidation of EPA-containing TGs with time and increased the moles of EPA in a single TG molecule. Total amounts of volatile compounds were greatest in the case of 1 : 2 mixtures of trieicosapentaenoylglycerol and tripalmitoylglycerol (EEE/PPP (1 : 2)). The major volatile compound was 2, 4, 7-decatrienal in all unoxidized TGs. Volatile components were essentially the same for unoxidized and autoxidized 1 : 1 mixtures of dieicosapentaenoyl-palmitoylglycerol and tripalmitoylglycerol (EEP/PPP (1 : 1)), and dipalmitoyl-eicosapentaenoylglycerol (EPP), whereas many different compounds were produced in autoxidized EEE/PPP (1 : 2). 1-Propanol, 2-butenal and 2-pentenal could be detected only in autoxidized EEE/PPP (1 : 2).
The TG structure is thus shown to affect the formation of volatile compounds during the autoxidation of EPA.
