American oak barrels

All sherries are improved by aging. The young baked sherries are strongly flavored and rough in taste. Oak chips are used commonly in competitive sherry types. The better wines are stored in fifty-gallon American oak barrels for several months to several years. American oak is favored because of the stronger aroma and drier taste of wines stored in it. The richness in flavor imparted by European oak apparently does not fit well into sherry flavors. It is interesting to note that American oak is favored also by Spanish winemakers. 

Rous, C., Alderson, B. (1983). Phenolic extraction curves for white wine aged in French and American oak barrels. Am. J. Enol. Vitic., 34, 211-215. 

The twelve new and twelve used barrels used in this experiment were made of American white oak (Quercus alba, fine grain) or French oak (Quercus petraea from the Allier forest in France), and were obtained from the same cooperage firm in Spain with the same specifications (medium toast level). The used barrels had been used three times for the aging of Monastrell wine and they were sanitatied before use by burning sulphur inside. The following barrels were used in the experiment 220 liter French oak barrel (3 new barrels and 3 used barrels) 220 liter American oak barrels (3 new barrels and 3 used barrels) 500 liter American oak barrels (3 new barrels and 3 used barrels) and 1000 liter American oak barrels (3 new barrels and 3 used barrels). 

Enologists must have available to them as much information as possible when buying barrels to produce high quality matured wines, although economic factors must not be forgotten. French oak barrels cost almost twice the price of American oak barrels and large volume barrels save space in the winery. 

AN New American oak barrels AU Used American oak barrels FN New French oak barrels FU Used French oak barrels... 

Fernandez de Simon B, Cadahia E and Mocha J. 2003. Volatile compounds in a Spanish red wine aged in barrels made of Spanish, French, and American oak wood. J Agric Food Chem 51 (26) 7671— 7678. 

The relationship of modern wine styles to aging wines in wooden barrels is described. The physical and chemical characteristics of different woods lead to the conclusion that white oak is best for wine cooperage. European cooperage oak samples had 161% of the extractable solids of North American samples and 154% of the phenol per unit of extractable solids, but American oak contributed more oak flavor to wine per unit of extract. Data are presented on the density and extractable phenol content of summer and spring oak wood, the characteristics of rapidly vs. slowly grown oak, the surface per unit volume effects of container size and shape, the variability among trees in flavor and extract content, the analysis of wood extract in wine, and the depth of penetration of wine into staves. 

From the considerations outlined, it appears one can usefully divide oak species having a reputation for high quality wine or brandy barrels into only two groups North American oak derived from Q. alba and related species and European oak derived from Q. sessilis and Q. robur. Woods derived from other oak species seem either to be inferior or to have been insufficiently tested to demonstrate their qualities. These two groups, North American and European, have sufficiently different extractives that it is often possible for an experienced taster to state which was used for wine or brandy storage. Within each group, however, the flavor... 

Spillman, P. J., Hand, P. G., Sefton, M. A. (1998a). Accumulation of volatile oak compounds in a model wine stored in American and Limousin oak barrels. Aust. J. Grape Wine Res., 4, 67-73. 

Waterhouse, A. L., Towey, 1. P. (1994). Oak lactone isomer ratio distinguishes between wines fermented in American and French oak barrels. J. Agric. Food Chem., 42, 1971-1974. 

The results of the descriptive analysis (Figure 4) showed that the origin of the wood caused little differences in most of the descriptors, only some were found in those descriptors related to aroma. A previous study showed that the concentration of cis-oak lactone was the most signiflcant difference between wines matured in American oak and French oak barrels (28). The age of the barrel produced the greatest differences in all the descriptors, especially as regards the intensity of the vanilla and woody character. When different volumes were compared, wines stored in 220 liter barrels had the highest scores in the aroma descriptors. 

Aging practices differ somewhat. British custom is to store the whiskey in uncharred oak barrels while American whiskies, both Rye and Bourbon, are stored in charred barrels. The color and solids of whiskey aged in uncharred packages are much smaller in amount and more water soluble than those of whiskey stored in charred packages. The charring also results in a bead of oilier consistency and greater permanence than the uncharred barrel imparts. 

Chatonet, P. and Dubourdieu, D. (1998). Comparative study of the characteristics of American white oak (Quercus alba) and European oak (Querqus petraea and Q. robur) for production of barrels used in barrel aging of wines. Am. J. Enol. Vitic. 30, 61. 

---