During the time that cognacs and armagnacs are absorbing the best qualities of the oak in their barrels to bring out their most exquisite flavours, being continuously in contact with the air, they will progressively lose some of their alcoholic strength.

This natural evaporation is called the “Angels’ share”, and represents between 1% and 3% each year, depending upon surrounding conditions: 20 million bottles per year for the whole region of Cognac, and 1.5 million for Armagnac.

As well as the Angels, these alcohol vapours feed a microscopic fungus – torula compniacensis – which covers the limestone houses of the region