We come to an extremely important part of the production process. Double distillation is the point where the master distiller can correct some "imperfections" of distilled wine or, conversely, not use its potential in distillation and subsequent maturation in oak barrels.
Alambic
A distillation apparatus called the Alambic has been used to distill cognac wine since the turn of the 16th and 17th centuries. It is made of copper and bronze and consists of the following parts:
cooking vessel
to pinch the wine with an onion-shaped "chapiteau" on top
swan neck
wine preheater
is only an additional (auxiliary) device
cooling tank
with spiral pipe around the inner circumference.
First distillation - premiere chauffe
The cooking vessel (Cucurbite) is filled with wine, which is brought to a boiling point by heating. The resulting alcohol vapors are gradually released and proceed through the chapiteau to the swan's neck (Col de cygne), where they condense to a liquid due to the colder environment. The hot distillate thus formed passes through a spiral (Serpentine) in a cooling vessel (Réfrigérant) filled with cold water and flows out as a slightly turbid liquid with an alcohol content of 27-32%. The distiller has a very important task to separate the so-called head, heart and tail, while only the heart from the first distillation called "brouillis" is used for the second distillation.
Second distillation - bonne chauffe
The second distillation cycle is exactly the same, but the result of it is clear distillate, so its heart with an alcohol content of 68-72%, is placed in oak barrels after distillation. According to strict regulations, the distillation period must end on 31 March of the year following the harvest of the grapes.