The third step in the whisky creation process is the distillation of the wash. This needs to be done in order to raise the ABV of the spirit.
As a quick review, in part 1 the grain ingredients of the whisky were mashed and mixed with hot water to create what is called wort. In part 2, the wort is combined with yeast and fermented. This fermented wort is called the wash.
In order to distill the spirit, the wash is placed in a still (either a pot or column still). The wash is boiled in the still, and since alcohol has a lower boiling point than water, the alcohol evaporates first.
The alcohol vapor collects at the top of the still, where it is cooled then condensed into liquid again. Depending on the type of whisky, the liquid might be distilled once or twice more, where the just-condensed alcohol is evaporated again then condensed.
Scotch is one example of whisky that is twice distilled, whereas Irish whiskey is thrice distilled. After the first distillation, the spirit is about 20% − 40% ABV. After the final distillation, the spirit is about 60 − 70% ABV.
Then, after distillation but before maturation, many whiskies are diluted with water to about 60%.
- Pot still – typically made of copper, and generally the required type of still to use when making Scotch whisky. It has a large bottom section and a narrower top section. The bottom section is where the wash is vaporized, and is then cooled and condensed in the narrow top section of the still.
- Column still – comprised of two columns—one column where the liquid is vaporized and rises through it, as well as already-condensed alcohol that falls through the first column. The second column contains the alcohol vapor that circulates through the column and condenses it.
- Spirit still – the still used during a second distillation.
How Variations in the Distillation Process Affect Flavor
The type (pot versus column) and shape of the still can substantially impact the flavor of the whisky. Glenfiddich is known to reproduce dents and bumps present on the original still if the still needs to be replaced, in order to ensure taste consistency.
Additionally, the amount of times the spirit is distilled will impact the flavoring. Scotch, for example, is distilled twice, whereas Irish whiskey is usually distilled three times. The amount of times a spirit is distilled can impact the smoothness of the beverage.
In part 4 of this series, we will discuss the third and final step to the whisky production process, maturation and bottling.
Have any questions on the distillation process? Have anything unique to add? Let us know in the comments below.