French oak barrels

Garde-Cerdan, X, Xorrea-Goni, D., Ancm-Azpilicueta, C. (2002). Changes in the concentration of volatile oak compounds and esters in red wine stored for 18 months in re-used French oak barrels. Aust. J. Grape Wine Res., 8, 140-145. 

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 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). 

Other studies have described similar results to those found in our research, that is, that ellagitannins are more abundant in French oak (26) and therefore, in wines matured in French oak barrels. So, the presence of ellagitannins enhances the color of wine and increases absorbance at 620 nm by fevoring anthocyanin-procyanidin type tannin condensations with acetaldehyde (purple pigments) and that foct also helps to explain the higher PVPP index values of wines fix)m new French oak barrels. They also prevent the development of brick-yellow color by preventing the oxidation of phenolic compounds (24). 

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. 

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... 

In terms of its volatile composition, Spanish oak is comparable to French oak of the same species. There are also two native species, Q. pyrenaica and Q. faginea, which have amounts of the oak lactones, vanillin, and eugenol that are statistically comparable to those in French oak, though wines aged in Q. faginea barrels have received particularly poor ratings by taste panels, earning low scores for the characteristic oak wood sensory attributes (Ferndndez de Simon et al. 2003,2006 Cadahfa et al. 2003). 

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. 

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. 

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