Characterization by gas chromatography-olfactometry of the most odor-active compounds in extracts prepared from acacia, chestnut, cherry, ash and oak woods

The aroma profiles of six different types of wood were evaluated by gas chromatography-olfactometry (GC-O) in order to examine their possible use as materials for making wooden barrels. The study revealed the presence of 46 odorants. Only one could not be identified, although information about its retention indices was determined in both DB-WAX and VF-5MS columns. It can be said that some of these odorants constitute the base of the aroma of these types of wood (sotolon, cis-2-nonenal, furaneol, maltol, 2-methyl-3-furanthiol, guaiacol and trans-2-nonenal). All the odorants were scored with a modified frequency higher than 55% in all the wood samples. The study revealed useful information about those compounds responsible for the greatest aromatic differences between the six wood extracts. Cyclotene, 2-acetyl-3-methylpyrazine, cis-whiskylactone and 2-acetylthiazole are some of the most discriminant compounds found among the samples. Finally, the study demonstrated that GC-O analysis has been able to detect some of these discriminant odorants for the first time, as was the case with 2-acetyl-3-methylpyrazine and 2-acetylthiazole present in acacia wood. Another new finding was that GC-O analysis allowed us to detect cis-whiskylactone in chestnut wood. Therefore, information provided by GC-O must be always taken into account.

► GC-O strategy allowed us to distinguish between the aromatic profile of 6 types of woods. ► Sotolon, furaneol, maltol (among others) constitute the base of their aroma. ► cis-Whiskylactone was detected in chestnut wood. ► Ash wood was characterized by high levels of cyclotene. ► Acacia sample exhibited high levels of 2-acetyl-3-methylpyrazine.