The distillation of whiskey
It is a good drinking experience to add some water. But when distill whiskey, the water must be removed completely, leaving only alcohol. This is the purpose of distillation. Using different distillation methods will also get different results. Distillation methods include traditional single distillation, continuous distillation and vacuum distillation.
What is the principle of distillation?
Distillation can't convert into any substance, but can separates different substances according to the boiling point. For example, the water's boiling point is 100°C, but alcohol will evaporate at about 80°C. Therefore, when we heat the fermented wort, the various substances contained in the liquid will evaporate one by one. By controlling temperature, let the gasified alcohol condense to liquefy. This process is distillation.
The principle of distillation comes from thermodynamics, using the changes of the state of matter (solid, liquid, and gas), heating first and then cooling. The distilled materials are heated to boiling, and the steam rises immediately, then enters the condenser through the tube, finally returns to a liquid state after cooling.
The key point of distilling whiskey is find the right boiling point. The boiling point must be slightly higher than 80°C in order to distill out the required chemical molecules and give fragrance in the whisky. Most single malt whiskey distillers use single distillation, using a pair of distillers to distill the wort fermented twice. After the first distillation,we can obtain the first distilled liquor. The distilled liquor have the alcohol concentration of 20%-25%, the first distilled liquor is distilled again. Which process is called "double distilling".
In some distillers, if the distillers are too busy to stay by the distiller, they will add a small piece of unscented soap in to the distillers when make first distillation. Which can prevent a lot of foam from boiling and reduce the probability of accidents. The boiling point of soap liquid is higher than that of alcohol, so don't worry that the soap liquid will come to the whisky liquor.