We’ve all heard the sentiment about “aging like a fine wine,” in reference to your favorite bottle of vino improving with the passage of time. But what about whiskey? Is older whiskey really that much better? The answer in short is yes… and also no.

Truthfully, it’s not that simple. The quality of whiskey depends on many variables beyond just age

The whiskey aging process is a complicated one that involves a lot of factors. How and where is the whiskey stored? What ingredients are in its mashbill?

It’s enough to make one’s head hurt, so we’re going to try to explain what aging a whiskey actually entails, what age statements mean, how a whiskey changes with age and if a whiskey can age past its prime.

How Is Whiskey Aged?

All those delicious flavors of caramel, toffee, marshmallow, tobacco smoke and more come from the whiskey aging process. In a nutshell, the whiskey aging process is all about the way the spirit interacts with the barrel.

When whiskey is fresh off the still, it is what is referred to as a “new make spirit,” white dog or moonshine. New make can taste like, well, more potent vodka hopped up on extra ethanol with fruity, grainy, corn forward notes, most times. In order for whiskey to turn into that mellow, delicious brown nectar we all know and love, the barrel is essential.

Different barrels and finishes contribute a great deal to the aromas and flavors of a whiskey, so the choice of barrel used, how charred it is and the amount of time the liquid spends inside the barrel are also major contributing factors to the final flavors.

The new make spirit is placed in barrels after distillation, where it undergoes a process called adsorption, according to Smithsonian Magazine.

During adsorption, the barrel acts as a sort of sponge and draws all those unpleasant aromas that come from the chemicals of the new make to its walls while simultaneously infusing the liquid with wood flavors.

Polymers like lignin and vanillin from the oak barrel give the spirit vanilla-like aromas. Lactones, types of esters, can also be present and impart a sort of buttery flavor. Wooden barrels also have tannins, which give whiskey its signature spicy flavor.

For peat-smoked scotches, it’s important to take into consideration the pre-existing phenols from the peat used to dry the barley grains. The interaction between these types of chemical compounds and the wood used also impacts the aging process of a whisky.

The length of the barrel aging process varies. Bourbon must be aged in new charred barrels and aged for at least two years to be designated a “straight” bourbon. Scotch, meanwhile, must be aged in wood for a minimum of three years.

A recent, uncommon process called “flash aging” ages whiskeys for less than a year. Flash-aged whiskeys are aged in smaller-than-usual barrels to massively boost the spirit-to-wood ratio. New York’s Tuthilltown Distillery, for example, uses flash aging for its flagship expression, the Hudson Baby Bourbon. Hudson Baby Bourbon is flash-aged for four months in 3-gallon barrels with low-frequency soundwaves pumped through the distillery’s warehouse to put the liquid in more contact with the walls of these barrels, which the distillery claims speeds up the aging process.

How Does Whiskey Change With Age?

Factors like the climate and where the distillery is located are major contributors to the way whiskey changes with age.

Hotter temperatures can lead to stronger chemical interactions taking place between the spirit and the cask, according to BBC. One reason for this is that heat causes the distillate to evaporate in what is known as the “angel’s share.”

In hotter climates — like Texas, for example — water evaporates faster, resulting in more leftover alcohol. In cooler and more humid climates like the Scottish highlands, the alcohol evaporates at a faster rate than water. In essence, scotches can spend a significantly longer amount of time in barrels than whiskeys from some parts of the Americas. Because of this, a general rule of thumb is that scotches that have higher age statements naturally have lower ABVs.

Whiskeys made in hot and humid climates, like India, may be considered to “age faster” due to the accelerated evaporation of alcohol.

As far as flavor is concerned, older whiskeys tend to take on more woody, tannic flavors due to the spirit spending a longer amount of time in the barrel. This is particularly true for whiskeys aged in new barrels that haven’t already previously imparted some of their oak and tannin to a different liquid. The harsh, ethanol-laced aromas mellow out over time spent in barrels, yielding more complexity. Younger whiskies, on the other hand, tend to be categorized as harsher, less “smooth,” more grain-forward and one-dimensional.

What Is an Age Statement?

The age statement is simply the amount of time the liquid was in contact with the barrel. Once the spirit is removed and bottled, its aging time effectively stops, rendering it inert.

The general rule with age statements is that older is better — and more expensive.

Age statements on the label of a whiskey with multiple components (a blended whiskey) indicate the age of the least-aged whiskey in the blend.

For example, a bottle of Dewar’s 25 Year Old Blended Scotch Whisky is composed of a variety of scotches with different age statements, yet the youngest one in the blend is 25 years of age.

Sometimes blenders use older whiskeys in blended whiskeys with younger age statements to add more complexity to the final spirit.

Many whiskeys don’t bear an age statement. These are referred to as non-age-statement, or NAS, whiskeys.

Can a Whiskey Be Too Old?

Yes, a whiskey can age past its prime.

Although whiskeys with exorbitantly high age statements can fetch wildly high prices at auctions, that doesn’t necessarily mean they’re going to taste better than their younger counterparts..

Typically, the sweet spot for scotches is around 12 to 25 years of age, according to Wine Enthusiast. Bourbon typically is at its best between 5 and 12 years old.

Extreme-aged whiskeys can be hit or miss, and some take on too much of the oak barrel’s flavor, rendering an unpleasant-tasting liquid that tastes far too tannic, bitter and woody. Several distillers, such as Four Roses Master Distiller Brent Elliott, have corroborated this:

“The barrel influence is so strong that it [becomes] bitter, astringent and has lost complexity,” he said in the Wine Enthusiast article.

So, Is Older Whiskey Actually Better?

At the end of the day, the best whiskey is the one that you like and feel is worth spending your money on. Most would consider well-aged whiskey to be superior to too-young whiskey — but too far in either direction tends to be a bad thing.

Taste is so personal that a great whiskey with a high age statement may taste great to one individual and terrible to another. Like all great and complicated things, it is subjective.

In short, age is nothing but a number.

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