When it comes to the process of making whiskey, much can be said about the barrel it gets aged in. But what do you know about the stills? Hint: it can make or break the overall flavor. And without a still, you wouldn’t have whiskey. While mash bills and barrel type take the spotlight, the still is quietly working hard in the background to create the actual spirit itself. If you’ve ever wondered how a still can affect the overall flavor, here’s everything you need to know about the different types of stills.
Pot vs. column stills
Pot stills are the most basic type of still. In its simplest form, a pot still has a large kettle or pot that gets heated from the bottom, boiling off the alcohol and allowing the vapors to be sent to a condenser and separated. Drilling down further, you start with what is essentially beer and heat it in the pot part until the alcohol changes from a liquid to a gas. As the vapors rise up, they’re captured at the top of the still and directed down the lyne arm and to the condenser. The condenser cools the vapors back into liquid form and the result is alcohol.
With a column still, the mash goes in near the top of the still and flows downward. At the top of the still, the mash is closer to the heating source. Once the mixture is heated throughout and begins to evaporate, the vapor rises through a series of partitions also known as plates (or stripping plates).
Distillation ends up being all about the alcohol vapors and the shape of the still dictates the vapor interaction. How quickly the vapor forms, the amount that rises, how much of it touches the copper and the speed at which it cools can all affect the way the whiskey tastes.
One of the key differences between the two is that pot stills operate mostly on a batch-by-batch basis. Conversely, column stills can be operated continuously, which is why they are sometimes known as continuous stills. Continuous stills can produce a spirit over 95% ABV, nearly pure ethanol whereas pot stills cannot. American craft distilleries often use a hybrid pot which has a pot still at its base but contains one or more columns. This gives the distillery a certain flexibility to produce different types of spirits.
Tall vs. short stills
Does the height of the still affect the taste of your whiskey? In short, yes, it does! Scientifically speaking, only ethanol (alcohol) vapors rise up at 173°. However, other chemicals (things like esters, phenols, fusel alcohols, etc.) can cling to the ethanol before it shrugs them off. So a taller still gives the ethanol more time to separate from these other chemicals. What does that mean for flavor? Shorter stills tend to deliver heavier flavored whiskey that clings to your palate. Taller stills deliver lighter whiskey. One is not better than the other but is all a matter of personal preference.
Wide vs. narrow stills
As with tall and short stills, wide vs. narrow stills result in a difference of flavor in two ways. First, with a copper still, the copper metal strips out sulfur, which is an undesirable chemical. When you have more ethanol interacting with the copper, more sulfur will get drawn out. Second, if the still has a larger surface area (wide still), esters, phenols and fusel alcohols will fall off the vapor stream and go back into the pot. As a result, a wider still produces a less oily and more refined spirit than the skinnier still.
So is any type of still, or shape of still, definitively better than the others? It depends on who you ask and what they most enjoy drinking. In our humble opinion, a debate like this one is best done over a few sips. That’s where RackHouse Whiskey Club comes in. We’ll ship small batch craft whiskey to your door so you can conveniently sip on the brown stuff and decide which is your favorite.