You know that yeast, he’s a Fungi (no apology here for the bad pun!) It’s true. Believe it or not, that sediment seen in most Belgian beers is a fermentation party in progress.
A happy yeast has plenty of sweet things to eat, and will party like it's 5-10 years from now.
We all know that beer is food. Which means, it is perishable. However, when used in secondary fermentation or bottle conditioning, it adds to the shelf life and complexity in flavor of the beer. As opposed to expensive filtration systems or pasteurization, the “noble” yeast left over from the brewing process is allowed to gallantly fight off further oxidation in the bottle, with the help of a little addition of sugar. The end result? A naturally carbonated beer, that in some cases, can be aged or cellared indefinitely.
It’s easy to understand why the mass-produced beer companies don’t go the bottle conditioning route. Although their products are filtered and pasteurized, they can produce a consistent product that is ready for consumption almost immediately. This means more can be sold in a short amount of time, without waiting for months or years for a return on investment, but, there’s always the question of quality. Most commercially-produced beers are lagers, and have a fairly short shelf life. You’ll likely see a “born on” or “best when consumed by” date on the bottle, and believe me, being the unfortunate recipient of a skunked beer is not a pleasant experience. On the other hand, bottle conditioned beers are ales, and don’t require all the fancy equipment to produce carbonation. This is how beer has been produced for centuries, and here is where being a little more “old-school” can be to your benefit.
I have seen and heard more and more frequently about beer geeks buying bottle conditioned beers and storing them away for future consumption. How long these beers can be cellared is a toss-up between the brewers’ recommendations and the matter of personal taste. You’d never want to age a lager, American pale ales, or wheat beers, as these are relatively low in alcohol and devoid of yeast in the bottle. You need that yeast in the bottle. Much like wine, beer is suitable to be aged due to the presence of yeast and residual sugars in the bottle. As long as the yeast has a food source, it continues to develop in flavor. Hence, a happy yeast is a hungry yeast with a supply of sweet things. Belgian beers, especially abbey ales, are excellent choices for aging, as most are malty and have an ABV of 6-8% or higher. Also, keep in mind that the bigger the bottle, the longer it can be aged. Not to say that aging smaller bottles isn’t possible, it’s just that the amount of beer in the bottle won’t age as long simply because of the amount of yeast and sugars present limit how much the flavor can develop. Your best bet would be to use 750 ml bottles or a magnum (1.5L) if it is available for your favorite beer. You’ll have to store it in a cool, dark, and dry place. It is also suggested to keep a corked bottle on its side like you would a wine bottle, to keep the cork moist during storage. Nothing worse than opening one of your aged beers and having the cork disintegrate and fall into the bottle. It’s also possible that air could get in through the dry cork and infect the desired outcome.
How long you can age a beer is indefinite answer. The best way to find out is to buy several of the beer you intend to age, and after 6 months to a year, compare the flavors side-by-side to a fresh bottle. You might be surprised at how the flavor develops over time; some may get a bit sweeter, some may take on a wine-like quality, and some may just blow your mind altogether. The real question is, can you resist pulling out one of those aged beers before your next tasting date?
See? The yeast wants to tell you something...next year.
