Aging of the Cognac

Aging

Without oak no cognac! The rule stipulates that cognac must age at least 2.5 years on oak casks. It’s the aging in oak that gives cognac its texture, color, intensity and complexity and would without this process stay as pale as for example a grappa. The oak used for cognac casks must be minimum 40 years old and only the lower part of the tree can be used. Before the wood is made to casks it is dried outside for a minimum of 3 years, which helps it get rid of some of more unpleasant and bitter tannins stored in oak. To types of oak dominate the production cognac cask Limousin and Tronçais. The tanins in Tronçais oak are well-known for their softness, whereas those in Limousin oak are recognized their balance. An eau-de-vie will extract more tanins when matured in casks made with Limousin oak. The size of the cask used for cognac is normally 350 liters, which has proven to be the optimal size, balancing amount of eau-de-vie with surface of oak.

The cognac casks are stored in cellars of the producers – in French called “chais”. The condition of each cellar will be different with regards to humidity and dryness which will affect the cognacs as they mature. Often the producers will move cognac from one cellar to another to get the effect of different storing condition and thereby optimize the aging of the cognac.

The most important part of the aging in oak is the extraction of tannin from the wood to the cognac, which causing of not only aroma but also gives cognac it characteristic color. Furthermore the oak allows the cognac to have indirect contact with outside air in the cellar. This leads to alcohol evaporation which also referred to as the angels share and causes the walls of the cellars to turn dark as a microscopic fungus develops with alcohol fumes mixes with humid air.

Final part of the aging is the dilution of the eau-de-vie with distilled water to bring their alcohol content down to 40 degrees. Only very old cognacs (above 40 years) are weak enough to be used without dilution.