Composition and odour of volatiles from autoxidised methyl arachidonate

Methyl arachidonate was subjected to autoxidation at room temperature either alone or in a water emulsion. Volatiles in the headspace were collected on Tenax and analysed by GC‐MS, and the amounts and identities of the major and minor volatiles were compared. Generally, the same compounds were formed in both systems, but whereas the amounts varied the changes were consistent with the role of water in lipid oxidation. Twelve volatiles accounted for 90% of the total, with oct‐l‐en‐3‐ol (30–40%), hept‐2‐enal (10–17%) and hexanal (6–17%) most prominent. Over 40 other volatiles were detected. The odour of individual components in both systems was assessed using a GC equipped with a sniffing port.