Study of Vanillin, Syringaldehyde and Gallic Acid Content in Oak Wood and Wine Spirit Mixtures: Influence of Heat Treatment and Chip Size

Vanillin, syringaldehyde and gallic acid are phenolic compounds which can be detected in spirits which have undergone a process of ageing in oak casks. A study has been carried out on the influence that the use of oak chips has on the aldehyde and aromatic acid content of spirits they are in contact with. These substances are to a great extent responsible for the organoleptic properties of drinks such as wine, rum, whisky and brandy, etc. This study tries to determine the influence of chip size and the time that wood must be subjected to heat treatment. It has been proved that chips particles with a diameter of 3-5 mm favour extraction processes, and that 5-6 h heat treatment allows an adequate decay of lignin, with the subsequent formation of aromatic aldehydes.