Leaving beer unopened at room temperature will ensure that it is at its best for an average of four to six months. After that, the quality will start to degrade. In general, you can expect a craft beer to last six to nine months in the pantry and six months to two years in the refrigerator. However, some craft brewers will tell you that it's too long.
Stored in a dark, cold place, such as a fridge, bottled beer will last up to 6 months. Hot bottled beer can go bad in as little as 3 months. For MadTree, most of its canned craft beers have a shelf life of 120 days. This includes their IPAs, Pale Ales, Kolsch, Amber and many others.
The darkest beers can stay on the shelves for up to 180 days. And there are even some that say they will stay good even after a year or more, mainly high-alcohol stouts and barrier-aged beers. Most types stay high quality for six months at room temperature, but you can keep them for up to a year in the refrigerator. You can't safely store beer in the freezer for a long time in the freezer, as the beer can and bottle explode at low temperatures.
Cask beer is often not pasteurized like canned or bottled beer because it's meant to be served faster. In the end, the ice crystals in a frozen beer will cause the beer to have a slightly flaky consistency with a high concentration of alcohol. It's just not the ideal way that most breweries, distributors and retailers want to sell craft beer. In the eastern United States, for example, most beer drinkers expect frothy clarity in most styles of beer, while many in the western United States view clarity with suspicion and suspect that beer is overprocessed.
Most craft beers come with an “expiration date” that indicates the period of time in which it is fresher and best tasting. While both beer drinkers and laboratory methods can agree on the question of whether a beer is transparent or not, there is more debate about the appropriateness of clarity. Have you found yourself at your local craft beer store with a 6-pack in your hand when you look down and see the “bottled with a date”? Because craft beer has gained such popularity, it's often available in mugs or taps that you can buy at your favorite brewery. The shelf life of beer will depend on the type of container, and ranges from a few days in the case of beer packaged in barrels, to several weeks in the case of keg beer or months in bottles and cans, and the latter enjoy the advantage of having the most hermetic seal.
Since craft beer tends to cost more than regular brands, you need to make sure you get what you pay for.