Lo-Fi Explainer: Distillation

Distillation. It's what makes whisky and other "hard alcohol" possible. Is it magic?

The Lo-Fi Explainer reviews commonly used terms & concepts so that you know what you're talking about.

Beer & wine are made through fermentation: you feed tiny organisms sugar, they eat it and excrete alcohol. That yields low-alcohol beverages, but distillation is the next step that gets you to higher-proof products like whisky.

Making whisky. That chocolate kiss looking thing is a pot still, one of the earliest tools for distillation.

Put different stuff in at the beginning of the process, and you get different distilled spirits at the end.

While you wouldn't drink wort, palatable fermented beverages like wine can also be distilled.

Essentially, distillation is a process of removing chemicals from a liquid by using their different boiling points. In this case, we want to take the alcohol out of the original fermented liquid so that we can drink it and leave the water behind. Because water boils at a lower temperature than alcohol, you can boil off the alcohol first and condense it.

The basic process.

This requires very specific temperature control, and water is still included in the end product (your whiskey isn't 100% alcohol by volume after all).

Some distilled spirits, like vodka, are distilled multiple times to get a "purer" spirit. "Contaminants" and "impurities" carried through to the final product are what give spirits taste - ethanol, the kind of alcohol humans can (kind of) safely drink, is naturally flavorless.

"Heads" and "tails" are what give whisky taste.

In whisky production, certain amounts of impurities are prized as what give unique tastes to the beverage. Part of a master distiller's job is to determine how much of the non-drinking alcohols (heads) and fusel oils (tails) to allow in to the final product. Oftentimes these are removed and then re-added to ensure consistency of taste.

When a whisky or other spirit touts that it is double- or triple-distilled (or beyond), that means the product of a first distillation has gone through the process multiple more times. This theoretically removes more impurities, although the materials used in the distilling process may add their own new ones.

General source & further reading: Whisky: Technology, Production and Marketing by Inge Russell (2003).