Study of the volatile composition of an aqueous oak smoke preparation

An aqueous smoke flavouring from oak (Quercus sp.) sawdust was obtained on the laboratory scale. Its qualitative and quantitative composition was studied by gas chromatography after previous extraction. A high number of compounds (215) was detected. In addition to the well-known smoke components, others, only recently described as smoke components, were also detected. In the first group there are aldehydes, ketones, diketones, esters, alcohols, acids, furan and pyran derivatives, syringol, guaiacol, phenol and pyrocatechol derivatives, alkyl and aryl ethers; in the second group the presence of some furan and pyran derivatives is noteworthy, as well as a significant number of lignin dimers in low proportion, a considerable number of anhydrosugars in very high proportion and some nitrogenated derivatives in low proportions. Differences between this oak aqueous liquid smoke and others previously obtained from several woods, under similar operative conditions, are due, not only to the absence or presence of some compounds, but also to the proportions of the different groups of components present in the preparation.