A contribution to the study of the enantiomeric composition of a chiral constituent in hazelnut oil used in the detection of adulterated olive oil

A method is proposed for the determination of the adulteration of olive oil with hazelnut oil which is based on the study of the enantiomeric makeup o f (E)-5-methylhept-2-en-4-one (filbertone). The possibilities of either usi ng a sample preparation technique or performing direct injection of the sam ples (i.e., without any kind of sample pretreatment) are considered and bot h simultaneous distillation extraction followed by gas chromatographic anal ysis and direct injection in online coupled reverse-phase liquid chromatogr aphy to gas chromatography are used. In both cases, a chiral stationary pha se is employed in the gas chromatography step and the determination of the enantiomeric composition of filbertone is recommended for an accurate evalu ation and quick control for detecting the adulteration of olive oil with ha zelnut oil.