How Long Does Bourbon Last After Opening It?

Whiskey lovers typically savor a quality bottle of bourbon, sipping carefully to enjoy the unique flavors, aromas, and other factors that combine to create this distinctive American liquor. But is it possible to savor a bit too much? Some may wonder whether or not their favorite bottle or a cherished rarity has a shelf life once it's been uncorked. Though whiskey and other forms of alcohol don't expire in the same way as food, there's definitely a best-by timeline: a few years at most.

The core issue at play that determines the drinkable lifespan of opened bourbon is oxidation. As the name suggests, it occurs when the whiskey (or any other substance) comes into sustained contact with oxygen, in this case via the air trapped in the empty parts of the bottle. Over time, oxidation transforms and degrades the flavor compounds in your bourbon, transforming the taste from the carefully crafted, barrel-fresh one to something typically less pleasant.

How much oxidation occurs and how fast your open bottle of bourbon lasts depend primarily on how full the bottle is. Bottles that are more than half full can last several years, while those under half should typically be consumed in two years at most, and those under a third full within a year.

These subtle changes in flavor aren't always undesirable. On a much shorter timeline, you need to let your whiskey breathe after pouring to allow a tiny bit of alcohol to evaporate, releasing crucial flavor compounds. Still, this should typically only be a short period, with experts recommending about a minute per year of aging the bourbon underwent.

Over longer time spans, those looking to stave off quality issues in their opened bourbon bottles have a few options, depending on their budget and dedication level to their spirits. For a low-tech solution, experts recommend decanting opened bottles of bourbon that you don't plan to drink within a few years into smaller bottles with less room for oxygen. Improper storage is among the biggest and most common mistakes people make when drinking bourbon. In addition, keep it in dark, cool areas to reduce any additional degradation caused by heat and light.

However, whiskey aficionados may consider investing in products such as specialized spray cans that pump non reactive gases like nitrogen or argon into the bottles. Another option is to vacuum-seal them, preventing oxidation even if there appears to be "empty" space. By returning the bottle to a state similar to when it was unopened, the spirit's lifespan is extended. With some basic awareness, it's easy to ensure your favorite bottle of bourbon stays in top condition for years to come.