Volatile composition of aged wine in used barrels of French oak and of American oak

This investigation studied the behaviour of the barrels at the completion of their cycle of use (5-6 years old) on the volatile composition of a red wine, Results showed that compounds from the wood such as vanillin. syringaldehyde and trans-beta-methyl-gamma-octalactone, which are important for the aroma of the wine, were lower than their threshold of perception. Vanillin. syringaldehyde and acetovanillone were found in higher concentrations in the wines aged in French oak, even though their initial concentrations are normally higher in the American oak. Cis-beta-methyl-gamma-octalactone was only found in concentrations above its threshold of perception in wines aged in the American oak barrels. In all the wines high concentrations of 4-ethyl phenol and 4-ethyl guaiacol were found, and these have a negative impact on the quality of the product, probably due to the presence of contaminating microflora as the barrels were old. (C) 2002 Elsevier Science Ltd. All rights reserved.