Can Bourbon Go Bad If You Never Open The Bottle?

Whether you've just discovered a new bottle of bourbon in the back of your liquor cabinet or were gifted a pricey, aged bottle this year for a special occasion, you might find yourself wondering if an unopened bottle of whiskey will ever go bad. The short answer is no, but that doesn't mean its quality won't eventually be affected.

"An unopened bottle of bourbon won't really go bad in the way wine or beer might," Chris Walster, whisky connoisseur at The Cask Connoisseur, told Chowhound in an exclusive chat. "Because it's a high-strength spirit, it's pretty stable if the seal is intact and it's been stored properly." Proper storage is the key here: Walster cautions that the storage method makes a big difference when it comes to deteriorating quality. "The bourbon itself isn't aging in the bottle, but things like heat, sunlight, a damaged cork, or evaporation can all affect the flavor," he says. "So, it's unlikely to become dangerous, but it can lose some of what made it enjoyable in the first place."

Bourbon is a variation of whiskey with a predominantly corn-based mash. To store this liquor properly, it's important to follow proper whiskey storage tips and know which mistakes to avoid. "The main one is keeping it somewhere too warm or in direct sunlight," Chris Walster says. "Heat and light can dull the flavor and make the bourbon taste flatter or harsher than it should." For example, store the bourbon in a cool, dark place (such as a liquor cabinet) rather than on a window sill or near a heater. And on the topic of temperature, avoid storage spots that see temperature fluctuations. "Repeated warming and cooling can put stress on the closure, which may lead to evaporation or a weakened seal over time," Walster explains.

Position matters, too. While it is best to store wine horizontally, which keeps the cork moist and structurally intact, bourbon — with its typical 40% alcohol by volume — is a very different story. "Bourbon should be kept upright, because long-term contact with high-strength alcohol can damage the cork and affect the seal," Walster says. 

If you do plan to crack open an old bottle for the first time, make sure the whiskey is still completely full (otherwise, there's a chance a broken seal led to evaporation), and that it has a normal whiskey smell. "Bourbon should still have those familiar notes of oak, caramel, vanilla, spice, and grain," Walster says. "If it smells musty, sour, corked, or just unpleasant, I'd avoid drinking it."