In a video titled “How Is Whiskey Made?” on the Reactions YouTube channel, everything you need to know about whiskey — from how it’s made to how it’s aged to its chemical compounds — is explained. Reactions is a video series “that uncovers the chemistry all around us” by answering “the burning questions you’ve always wanted to ask.”
So how is whiskey made? A quick rundown:
First there’s the yeasts and the sugars. The yeasts eat the sugars and produce alcohols as a byproduct (yes, plural alcohols). Those sugars can come from multiple sources depending on the whiskey. It comes from malted barley for Scotch, from at least 51 percent corn for bourbon, and from at least 51 percent rye for rye whiskey.
Those grains are turned into a 5 to 10 percent alcohol by volume beer-like substance. Then the liquid is put through a still, which heats the liquid. Methanol — the type of alcohol that can make you blind — boils at 148 Fahrenheit. That part is called the “heads” and is discarded. Ethanol — the type of alcohol you want to drink — boils at 173 Fahrenheit. That’s the part you want to keep.
Once it’s distilled, the whiskey is put through chambers. Flavor molecules dissolve into the liquor, like ethyl hexanoate (tastes like apples), and diacetyl (tastes like butter). The stills are usually copper, because copper reacts to sulphur and removes the bad sulphur tastes.
Finally, the liquid is put into barrels. It picks up color in the barrels, as well as phenolic structures like guaiacol (smokey) and m-cresol (bandaids).
Move the liquid from the barrels to bottles after a few years and there you have it: A perfectly good whiskey (or whisky, depending on where it’s from). Watch the whole video for the complete experience. As an added bonus, Reactions throws in a Scotchy Scotch Scotch clip from Anchorman.