Cider is turned into Calvados by the distillation process whereby the alcohol is separated from the water: when the cider is heated, having a lower boiling point than water, the alcohol it contains is boiled off first.
The still is the instrument used to collect this alcohol-charged vapour and condense it in order to obtain a brandy in which are found the volatile substances making up the main elements of the bouquet.
Two types of stills for making Calvados:
Pot-still or reflux still (alambic à repasse)
Required for making AOC "Calvados Pays d'Auge", it is the traditional still made of copper elements and involves a double distillation.
The cider is heated in the pot (boiler). The alcohol vapour rises, is collected in the onion, olive or Moor's head-shaped dome, goes along the swan neck then through
the coil which plunges into a tank of cold water. On coming into contact with the coolant, the vapours condense into a liquid. The "heads" and "tails", the vapours at the beginning and end of distillation which are very rich in higher alcohols and will be redistilled with the next cider, are eliminated to obtain the "brouillis" or "petite eau" containing 28 to 30% alcohol.
Reflux column still (alambic à colonne "de premier jet")
Mandatory for making Domfrontais Calvados, it is also used for AOC Calvados.
The first column receives the cider in its upper section. On the way down the cider passes from plate to plate. The application of heat causes the most volatile substances (water and esters) to vaporize. The water vapour produced from the depleted cider rises up again and is enriched as it bubbles through the cider with the volatile elements – alcohol, esters and aroma components.
They are finally concentrated in the smallest column which delivers brandy directly at maximum strength 72%. The column still has to be fitted with three draw-off taps to separate the "heads" and the "tails" and keep just the "heart" of the distillation.