How Distillate Becomes Whiskey
I’m about to enrage the people who are more savvy and aware of the subtleties of making whiskey. Brace yourselves for more gross over simplifications. At the end of this, you’re going to wonder why this all seems so mysterious. I did too, and I plan to dispel the mystery. That’s another post though.
whiskey is flavored vodka
I know, it’s irritating, right? It’s true though. If you haven’t read the previous posts in this series about how beer becomes distillate, you should start there. To recap though, here’s the process.
- Yeast is a fungus. When it eats sugar and has very little oxygen, it reproduces less and produces alcohol. Sugars are mixed with water and yeast is introduced. That sugar can come from grains, fruits, or other sources.
- The product that follows step 1 is beer, cider, wine, or something similar depending on what the sugar comes from (beer from grains, wine from grapes, cider from fruit, etc.) In the case of making liquor, this doesn’t need to be drinkable and usually isn’t.
- Usually using heat, the alcohol is separated from the rest of the brew. This can be done because alcohol evaporates at a lower temperature than water. By heating the brew to the boiling temperature of alcohol but lower than the boiling temperature of water, alcohol is easily separated. This is done using a metal container and some pipe, usually copper, and the tool is called a still. What comes out of the still is vodka.
- Vodka has many names. If the beer is made from agave, it’s known as silver tequila. If it’s made from wine it is brandy. If it is made from grains, it is moonshine. If it is made from sugar cane, it is rum. In any case, when it comes out of the still it is clear.
- If you infuse vodka with cloves, it’s called gin. If you age tequila in oak for at least 2 months, it becomes respado. When it is aged for at least 1 year but not more than 3 it becomes anejo. When you age grain alcohol (moonshine) in oak, it becomes whiskey.
Fine, it's oak flavored vodka. How does it get the flavor?
Caramelization is the process of removing water from something and breaking down the sugars in it. Most countries have really strict laws about what kind of wood can be used to flavor whiskey(except Canada… Don’t drink Canadian whiskey. It’s anarchy in the whiskey industry up there). This is a primary reason oak is used. Also, oak makes the most delicious whiskey but that’s a matter of opinion and up for debate.
Oak can be caramelized by burning it. This is the most common way of doing it, and there’s a whole science and art to charring the inside of a barrel. Carmelizing oak creates sugar that sweetens the distillate and gives it that deep amber color. Depending on the char, this could be a bold, nutty flavor or a sweet, vanilla profile.
How the atmosphere gives it flavor
Oak barrels are normally stored in a cellar or a warehouse with some form of climate control. Over the course of the year based on where the barrels are stored and how the weather changes, the atmospheric pressure will increase or decrease.
This pressure shift causes the distillate to be pulled into the charred oak and then pushed back into the mix. Rotating the barrels occasionally can help speed up the process. As the seasons pass, the process happens multiple times turning the distillate into a new color and passing the sugar from the carmelization process into it. Once it has aged long enough, a master distiller will declare it finished and it will be cut if necessary and bottled.
How does it all stay in the barrel?
Trick question, it doesn’t! The pressure is strong enough sometimes that some of the distillate gets pulled out of the barrel. This is known as the angel’s share. Because of this, when an old barrel is opened there is a usually less volume in it then when the process started. A barrel aged long enough may even be empty! This, along with the cost of long-term storage, is part of why those really old bottles are so expensive.
As a note, distilling is heavily regulated and usually requires special permits to do. This site is not intended to help you make whiskey, just to understand it.