Extraction of volatile and semi-volatile components from oak wood used for aging wine by miniaturised pressurised liquid technique

P>A miniaturised pressurised liquid technique has been applied to the extraction of volatile compounds present in oak wood samples used in making wine. The solvent extraction performed at high pressure and temperature has allowed the detection of a large number of compounds some of which present sensory and antioxidant properties. The effect of the main process variables on the efficiency of extraction has been studied: the composition of the extracted fraction depended mainly on the polarity of the solvent and the extraction temperature had a high influence on the extracted amount, while the effect of static extraction time and pressure were almost negligible. The highest recoveries were obtained for dichloromethane, for two static 10-min extraction cycles at 60 degrees C. Among the solvent extraction techniques, miniaturised pressurised liquid extraction presents several advantages, such as the use of reduced amounts of both sample and solvent and high extraction efficiency.