Effect of dietary lipid sources on odour-active compounds in muscle of turbot (Psetta maxima)

Odour-active compounds in muscle of turbot (Psetta maxima) fed experimental diets containing fish oil (FO), soybean oil (SO) or linseed oil (LO) were investigated by a gas chromatography/olfactometry technique. Thirty-one are as associated with odours were detected in muscle extracts. Among the compo unds responsible for these odours, 23 were formed by oxidation of unsaturat ed fatty acids. Independently of diet, (E)-2-penten-1-ol and (E)-3-hexen-1- ol contribute strongly to the odour of turbot. (E,Z)-2,6-Nonadienal, (E)-2- pentenal and (E,E)-1,3-(Z)-5-octatriene seem to contribute strongly to the odour of turbot fed diets containing high levels of n-3 PUFA (FO and LO gro ups). Hexanal and decanal show a high detection frequency in turbot fed die ts containing vegetable oils. Odorous compounds which are not formed by lip id oxidation (methional, 1-acetyl pyrazine, 4-ethyl benzaldehyde and 2-acet yl-2-thiazoline) were not affected by dietary lipid sources. (C) 2001 Socie ty of Chemical Industry.