Buzz
Beer continues to age after it's been bottled, much like wine. However, unlike wine, this process typically doesn't improve its quality.Your parents are moving to a smaller space, and you've volunteered to help. But as soon as you're given the task of sorting through the attic, doubts start creeping in. Amidst boxes of old keepsakes, outdated clothes, and random household items, something catches your attention. Sitting on top of a wall stud, you find a dusty bottle — and it's still sealed.
It's beer — a brand you don't recognize, and it still has its cap on. Feeling a mix of curiosity and uncertainty, you wonder what it would be like to try a decade-old, attic-stored beer. Will it have matured like wine, or will it have gone flat and lost its alcohol content?
Beer, like wine, continues to age after being bottled. However, unlike wine, this process typically doesn't result in an improvement in flavor.
As beer ages, it continues to ferment, but don’t expect it to improve. While aging beer won’t make it unsafe to drink, the taste can suffer. It will likely become flat, either by losing its flavor or developing an unpleasant one. The flavor peaks in the first few months after bottling, and once that happens, the proteins that contribute to beer's unique taste will begin to degrade, resulting in a beer that feels one-dimensional or even disappointing.
However, there's an exception to the 'drink it quickly' rule: beers with higher hop content and alcohol levels (usually 9% or more), which are specifically brewed for aging. These beers are designed to endure the aging process. Their proteins may still break down, but they are made to withstand it. Many of these are 'living beers' containing yeast from the brewing process that continues to evolve and develop more complex flavors over time [sources: The Kitchn, The Professor's House].
So what about the alcohol content? As beer ages, does its potency decrease? In short, no. The alcohol content in beer (and wine, too) is established during fermentation and remains unchanged over time. Yeast consumes sugar (or other carbohydrates) and produces carbon dioxide and ethanol alcohol. When the yeast produces alcohol, the alcohol eventually kills the yeast, which stops any further alcohol production [source: Wine Spectator].
Why do some beers have higher alcohol content than others? The alcohol level is determined by the type of yeast used in fermentation. Most yeast strains can only tolerate alcohol concentrations of 10 to 15 percent before the alcohol becomes toxic to them. As a result, beers can range from 5 to 21 percent alcohol by volume, which is a measure of how much of the liquid is alcohol [sources: Alba-Lois, Beer Advocate].
