n-Pent-l-en-3-ol and n-Pent-en-3-one in oxidized dairy products

Summary Pent-1-en-3-ol and pent-l-en-3-one were isolated in approximately equal amounts from buttermilk obtained from oxidized cream. The two vinyl compounds were identified by combined gas chromatography and mass spectrometry. The flavour of pent-1-en-3-ol is comparatively mild being detectable in water, skim-milk, butter oil and butter at 3 pts in 106, 3 pts in 106, 1 pt in 105 and 1 pt in 105, respectively. The flavour of pent-1-en-3-one is approximately 1000 times stronger being detectable in water, skim-milk, butter oil and butter at 1 pt in 109, 3 pts in 109, 5 pts in 109 and 5 pts in 109, respectively: these concentrations are of the same order of magnitude as for the compound responsible for metallic flavour, oct-1-en-3-one. The formation of pent-1-en-3-ol and pent-1-en-3-one is discussed.