Tennessee Whiskey: The Aging Process

Let’s see how many clichés can we toss out here: Good things come to those who wait. Patience is a virtue. Only time will tell. All of these ring true when it comes to Tennessee Whiskey. In fact, you could even make the case that time is the most important ingredient in whiskey. Well, some might say the alcohol is the most important ingredient, but hey, it’s time that makes the alcohol so tasty.

There’s a lot of chemistry that goes into the front end of the whiskey-making process, but after all the mixing and mashing, there’s just waiting. A lot of waiting. Let’s say you decide to forego the waiting—that’s unaged whiskey, or what is more commonly referred to as moonshine. It’s harsh. It’s potent. And you if you really want to savor your sipping, you need to age it.

Right off the still, we filter our white whiskey through charcoal with the “Lincoln County Process” and transfer it to charred oak barrels. This brings out the color and flavor that we’re all familiar with, but of course it takes time. The type of wood used is very important: they must be oak barrels. Not just any old tree will work, they need to be oak, and they need to be virgin, unused barrels or else they will absorb the flavor of what was in there before. That’s right, once a barrel ages Tennessee whiskey, it can never be used for it again.

The interior of the barrels must also be charred before adding the unaged whiskey. That burnt, charred layer inside the barrel does a number of things through a process called adsoption. The chemical makeup of young whiskey could be harsh to most, but the charred barrel’s wall draws out those molecules. While that’s happening, the wood imparts that signature flavor and color of TN Whiskey, slowly infusing it with flavors that are buttery, wood-like, and similar to vanilla.

Once the whiskey is in barrels and those magical reactions begin, the barrels must be stored properly. The most difficult and deciding factor during storage is temperature. Think for a minute about how long Tennessee Whiskey has been around. Now think about how relatively new interior temperature control is… here’s what we’re getting at: Great Great Great Grandpa Charles didn’t have any kind of HVAC situation back when he started making whiskey. So it’s important that we maintain that authentic exposure to the elements when we make our whiskey. It’s these seasonal temperature fluctuations that make Tennessee such a great place to produce whiskey. During the heat of summer the pores of the barrels expand, drawing in the whiskey into the wood. Then during the cold of winter, those pores contract, extracting flavor and color as the whiskey is forced from the wood back into the barrel. Year after year, this process repeats. Evaporation, condensation, and all those terms we kind of forgot about from science class are coming in to play here, but at least this time it’s fun. The whiskey is very sensitive to altitude as well. So much so, we rotate the height of our barrels in the warehouse regularly in order to provide consistency to the finished product.

Those are relatively broad strokes, but everyone agrees that the process outlined above is the most common and effective way to make Tennessee Whiskey. But like most art forms, the difference between good and great is what you do in the gray areas of technique and philosophy. So… just how long do you age whiskey? How do you know when it’s ready? Legally, Tennessee Whiskey doesn’t have to be aged for a minimum period of time but we prefer the four year mark as a starting point. We recently bottled our own Tennessee Whiskey after what might have been the longest four years of our lives, and we’ve gotta say, it was worth the wait.