The use of wine barrels (especially oak barrels) to store and age wine is a centuries old tradition (and solution). Wine aged in oak barrels is enhanced with the addition of vanilla and oak overtones. Wooden Wine Barrels also allow for a small amount of evaporation of the contents during the aging period.
French Oak was considered especially desirable wood for making wine barrels for many years. Most French Oak comes from one or more of the forests that were planted in the days of Napoleon for shipbuilding. Five primary forests used for wine barrel production are Allier, Limousin, Nevers, Trancais and Vosges. Each of these forests produces wood with distinctive characteristics involving tightness of the wood grain as well as the amount of oak flavors that are imparted to the wine. Tight grained wood tends to impart the Oak characteristics (vanilla, spice and butter flavors) much more slowly than wood with looser grain. Winemakers select wood for their wine barrels from different forests for the effect on the finished wine.