Beer has been around a while. The oldest beer recipe dates back to 1800 BC, and is part of a poem dedicated to Ninkasi, the Sumerian Goddess of Beer. Standing water might grow bacteria, but with hops, yeast and a little sugar, you get beer.
Can beer go bad? Yes, but the shelf life varies depending on brewing methods and storage conditions.
How Long Is Beer Good For?
The shelf life of beer is dependent on a lot of factors. According to beer geek Jeff Flowers, beer is a combination of at least four basic elements: Malt extract, yeast, hops and water.
Once those four factors get to work, beer flavoring can include everything from peanut butter to Nutella to chocolate to oranges. The sky is the limit.
Beer in a growler from a micro brewery can be kept for a week or two, but once the seal is broken it should be enjoyed within one or two days. Air exposure will cause the beer to oxidize and ruin the flavor.
If properly chilled, bottled beer should last for at least four months, and canned beer can be kept for twelve months. "Skunky" beer flavor is also known as "light-struck" beer.
Beer develops a "skunky" flavor when light-sensitive hops are exposed to too much light.
This is why beer is often stored in brown or green bottles, as it reduces the reaction of the isohumulones in the hops to direct light. Chemists from UNC at Chapel Hill triggered the isohumulones in beer with lasers and were able to generate a "skunky" smell and flavor.
Because light exposure triggers the "skunky" response, canned beer has the longest shelf life. Experts from Professorshouse.com strongly recommend buying beer from the cooler rather than from the liquor store display floor.
If chilled prior to purchase and kept cold, it should keep for twelve months in your refrigerator. Room temperature beer degrades quickly.
Does Bottled Beer Go Bad?
Beer bottled in clear bottles has a shorter shelf life than brown or green bottled beers because of the risk of hops degradation. Other considerations include alcohol level and hops concentration.
Per the experts at Tastings.com, more alcohol and more hops means a longer shelf life. For lighter beers with lower hops and alcohol, the freshness window is approximately four months if the beer has been consistently chilled.
Heat causes beer to oxidize and leaves a flat, papery flavor.
How to Tell If Beer Has Gone Bad
If you find beer at the back of the pantry, dump it. It's been warm too long. Heat exposure causes beer to oxidize. It may not be skunky, but it will taste flat and unappealing.
If you find beer at the back of the refrigerator, open it and smell it.
Skunked beer is unmistakable and nasty to smell, and appalling to drink. Discard immediately, and buy some cold and fresh.
Does Beer Expire? – The Expiration Date On Beer
The "freshness date" or drink-by date on bottled beer is generally four months from bottling to expiration. This is the time period in which the beer will taste exactly as the brewer intended.
When does beer expire, and what can you expect if you drink it past the expiration date? Many beers are good for six months, or two months past the "drink by" date.
If you drink it within the freshness date but still notice a flavor discrepancy in your favorite beer, be aware that the bottle may have been exposed to heat, or stored at room temperature for a time.
Best Way To Store Beer
How long does beer last? For the best flavor representation, beer should be bought cold and stored cold. Micro brew in a growler should be opened within two weeks of purchase and finished within two days of opening.
Bottled beer should be enjoyed within four months of purchase. Canned beer can be stored cold for up to twelve months. Age doesn't improve beer as it does wine.
When purchasing beer from a store, buy from the cooler and refrigerate immediately. Open and enjoy within four months.
When buying from a micro brewery, keep the growler cold and enjoy within two weeks.