Will a beer left sealed in the bottle ever expire? The short answer is yes. But the longer answer is that it depends. Confused? You're not alone.
The life of a beer doesn't end once it's finished fermenting and is sealed into bottles. Like wine, beer continues to age and change over time. They're at their peak of freshness and flavor the first few months after bottling, but then things slowly decline. Flavors start to fade, oxidization occurs, and the protein structure that gives the beer body starts to break down.
But saying that beer actually expires is a bit misleading. It doesn't actually spoil or become unsafe to drink. It will just start to taste flat, flavorless, and unappealing.
How long a beer stays fresh and how fast it becomes unpalatable depends on the specific beer. Most craft beers stored at a stable temperature and out of the light will be good for about a year before starting to turn. Look for a bottling date or an expiration date on the bottle's label, as well. Many breweries have started printing this information for our benefit.
Some beers, particularly bottle-conditioned ales with an alcohol content of 9% or higher, can be aged for longer than a year. They experience the same breakdown in flavor and structure, but this has been calculated to actually improve the flavor of the beer. Hop bitterness fades away while malts take on a deeper, more honey-like flavors. Other flavors emerge that may not have been perceptible before. It can be a fun experiment to put away a few bottles of a strong beer like a barley-wine or a barrel-aged stout, and then open a bottle every few months!
Related: The Real Truth About Skunked Beer
(Image: Flickr member DeusXFlorida licensed under Creative Commons)
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Very dark beers like Deschutes Abyss and Lost Abbey Angel's Share are great for keeping and aging in a cool dark place. I recently attended a vertical tasting of Lost Abbey's Angel's Share, there were bottles from 2006 to 2010. I think we all agreed that the 2006 bottle was by far the best of the group.
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I had a bottle of a Smoked Porter that I got from the Alaskan Brewing Company in 1995, and kept it double-wrapped in foil in a fridge until 2001. A little flat, but delicious. Of course, after 6 years I couldn't remember what the original tasted like.
I have several friends who "cellar" their beers. I, however, lack the space and the patience. If there's beer in the house, it will be imbibed within a week or two.
All right, I'll ask it - what about macro brews? I appreciate the tips about the craft beers, as we have a bunch of those in the beer fridge at the moment. However, my husband is also sitting on a mountain of macro brew cans from the last tailgate we threw. He thinks that they will never go undrinkable. He may be right in that they taste like water at their peak, but I digress. Any shelf life for these?
I use up old bottles of beer to boil lobsters in.... just add water and beer in equal amounts and tons of salt, unbeatable flavor!
The shelf life of a beer can also be shortened the COLOR of the bottle as well!!
Clear, green, and blue bottles do not block all the rays from the sun as well as a brown bottle. If you get a beer that is a bit 'skunky' this is usually due to a break down of elements of the tasty brew from UV.
Best bet over all is to keep them in a dark cool area for storage.
NSane - a lot of macro beers have a born on date. I would guess its probably good for 6 months, tops, if stored in a cool place. Being in cans has an advantage, as they aren't susceptible to the skunking capability of light. Hops work as a preservative, and those macros just don't use enough hops to keep the beer tasting better longer.
Six months for a macro sounds about right.
Cellaring sours, or any bottle conditioned beers are always good. I brew at home, and I always find the last one is the best one, because they've hung around long enough to get really good.
Do not, however, cellar your IPA's. The hoppiness that you are looking for starts to dissipate after only a couple months. If you cellar an IPA for six months, you'll basically have a strong pale ale.
The day i was born my dad passed out bottles of st. Pauli Girl in celebration. My aunt saved one and gave it to me on my 21st birthday. At this point, it's mostly sludge and looks more like a science experiment than a beer - but either way it's a cool looking decoration.
ugh... I don't know... if it reeks so bad that you can't smell anything else for two days, I think it's spoiled.