Study of the enantiomeric composition of chiral constituents in edible oils by simultaneous distillation-extraction. Detection of adulterated olive oils

A method is proposed for detecting adulterations of olive oil with hazelnut oil at percentages as low as 5%. The method is based on the identification of R- and S-enantiomers of E-5-methylhept-2-en-4-one (filbertone) and invo lves the use of simultaneous distillation-solvent extraction in the sample preparation step and subsequent gas chromatographic analysis with a chiral stationary phase. Relative standard deviation values obtained from three re plicates of adulterated mixtures of olive oil and hazelnut oil (95:5) were less than 9% for both R- and S-filbertone.