Comparative study of different extraction techniques for the analysis of virgin olive oil aroma

Abstract

Headspace solid-phase microextraction (HS-SPME), simultaneous distillation/extraction (SDE) and closed-loop stripping analysis (CLSA) coupled to gas chromatography/mass spectrometry (GC/MS) were used to study virgin olive oil, with the goal of detecting large numbers of characteristic volatile and semi-volatile compounds. More than one hundred compounds were detected in the olive oil extracts, and their percent amounts obtained by each technique were calculated. Qualitative and quantitative differences of virgin olive oil volatile profiles were observed applying the three extraction techniques. SPME showed a higher affinity for alcohols and ketones, while CLSA achieved the highest percentages of esters and hydrocarbons. Finally, the highest extraction of total terpenoid compounds occurred with SDE and CLSA, where CLSA allowed extracting the highest percentages of the most of them. SDE extraction caused the thermal degradation of the oil sample, which resulted in a high percentage of aldehydic compounds.