Distillation and ageing – how cognac is made
Touchdown in this part of France and you can’t escape cognac. This famous local brandy takes its name from the Cognac area and is now an international brand.
Like champagne, there are strict rules on the making of cognac and what it can be made with. And to bear the cognac name, the brandy has to be made in one of six regional zones (see cognac area for more).
Cognac is made by distilling wine, so the first stage is as with wine production – growing, harvesting and pressing the grapes.
Some grapes picked from the vineyards in the cognac producing area are used to make the apéritif pineau or wine, but most are destined for making cognac itself.
One of the restrictions imposed on cognac producers is the variety of grape that can be used.
In fact most cognac is made with the ‘Ugni blanc’ variety, France’s most widely-grown white wine grape. However it can also be made with Folle blanche or Colombard grapes too.
The key to producing cognac is distillation of the wine not once but twice. This double distillation is obligatory and essential to giving cognac its unique taste and aroma. The second distillation is known as la bonne chauffe.
There are also rules on the still or alambic charentais that is used for the distillation process, as well as for the barrels that are used for the crucial ageing process.
Once distilled, the liquid produced – known as eaux-de-vie – must be aged for a minimum of two year in oak casks to allow the cognac’s flavours and colour to mature. The barrels must be made from two species of oak from either the TronÃ§ais forest in the Allier department in the Auvergne, or more usually from the Limousin region that neighbours Poitou-Charentes.
During the ageing process part of the eaux-de-vie evaporates out of the barrels and this is known, rather evocatively, as la part des anges or ‘the angels’ share’. The alcohol fumes feed a fungus which appears on the walls and ceiling of the storeroom or chai where the cognac is aged - on a tour of the warehouses you will always see blackened walls. In the past the presence of this tell-tale fungus was used to detect places where cognac was being made illicitly!
Once ready, cognac is graded according to its age:
* VS (Very Special) is the youngest cognac, though it must have been aged for at least two years
* VSOP (Very Special Old Pale) has to have been aged for a minimum of four years
* XO (Extra Old)/Napoleon) is the oldest cognac, having been aged for at least six years