Determination of (E)-5-methylhept-2-en-4-one in deodorised hazelnut oil. Application to the detection of adulterated olive oils

The presence of (E)-5-methylhept-2-en-4-one (filbertone) in a hazelnut oil, deodorised in a laboratory system using nitrogen as stripping pas, is stud ied regarding its usefulness as a chiral marker for detecting adulterations of olive oil. The analytical method involves the use of both simultaneous distillation-solvent extraction as a sample concentration step and a chiral stationary phase in the subsequent gas chromatographic analysis. The proce dure is simple, rapid, effective for detecting adulterations of olive oil w ith hazelnut oil and can reduce falsely negative results obtained if conven tional parameters included in current regulations are exclusively considere d when establishing purity in olive oils. (C) 2000 Society of Chemical Indu stry.