Alcohol Distillation and the Science of Fermentation
Fermentation is an age-old process in which yeast consumes sugar to produce alcohol. Through distillation, the ancient practice has become an indispensable element of many of our favorite beverages. Alexander of Aphrodisias first mentioned distilling water around 200 CE; Arab alchemists Zosimus of Panopolis (3rd Century CE) and Abu Bakr al-Razi (9th Century) both worked extensively on distilling liquids as early as 300 CE and 9th Century respectively.
About 75% of a fermented wash consists of water and alcohol with minimal flavor; the other 25% comprises various organic chemical compounds known as congeners which give alcohol its distinctive flavors.
Distillation separates and concentrates various compounds by their unique boiling points. Ideally, each compound boils at its specific temperature before collecting as pure vapor; this idealized model is governed by Raoult’s Law and Dalton’s Law that assume vapor-liquid equilibrium has been reached.
Distillation doesn’t always happen this way in real life, however; distillers must utilize various tools, methods, and techniques in order to separate and concentrate the compounds they want for their desired end product. One key tool in their arsenal is their still – this tool comes in either pot or column varieties; when used to separate compounds by time while in columns position is used.