Advertising a beer as "bottle-conditioned" might sound like a clever marketing ploy - after all, couldn't every beer sold in a bottle technically be thought of as bottle-conditioned? Well, it turns out that this particular feature is more than just fancy words!
Bottle-conditioning simply means that the beer is sealed into the bottle with a little yeast and extra sugar. The yeast consumes the sugar and carbonates the beer within a few weeks. This is actually how beer has been carbonated for centuries, which you'll also sometimes hear it called "real ale."
The invention of machines that can force carbon gas into beverages during bottling (or canning) has largely eliminated the need of bottle-conditioning in the past several decades. With this technology, breweries can sell their beer immediately after bottling and the beer is much more consistent from bottle to bottle.
But bottle-conditioning has been making a resurgence as more craft breweries, like Boulevard Brewery, get back to the roots of brewing and experiment with traditional styles. Some use different yeasts for the initial fermentation and the bottle-conditioning, which adds additional - and sometimes unpredictable - flavors and nuances to the final beer.
There are two ways to drink a bottle conditioned beer. If you like the strong flavors and don't mind a bit of grit in your beer, swirl it gently to mix the yeast with the beer before pouring it into a glass. If you'd like a cleaner flavor, pour the beer into a glass without swirling it and then leave the last few drops in the bottle to catch the yeast sediment.
Do you have a favorite bottle-conditioned beer?
Related: The Real Truth About Skunked Beer
(Image: Flickr member Jinx! licensed under Creative Commons)
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If you've ever had homebrew, you've had bottle-conditioned beer. It's also why homebrew beers can get significantly stronger the longer you let them stay in your fridge.
Ommegang brewery makes a bunch of bottle conditioned ales. One of them they actually age in caves nearby!
Mmmm I love the yeasty swirl.
Was drinking a home brewed stout last night. Drank a single bottle in two sessions, the second was a lot stronger tasting than the first for just the reason you describe with the yeast and sugar in the bottom.
Also, one problem with real ale (I drink a lot of the stuff back home in the UK) is that sometimes they have a tendency to explode on you if you jiggle them too much before or while you're opening them.
We have some ale bottle-conditioning as I type. Yum.
My fave is Racer 5!
Bottle conditioned and Real Ale are not the same thing at all.
Google "Campaign for Real Ale" and do some reading.
Bottle conditioned beer is still a living product. It doesn't go through the process that filters out and kills the yeast like most mass-produced beers do.
The nice thing about bottle-conditioned beers is that if you are a homebrewer and are careful with sanitation, you can start a yeast culture from bottle-conditioned commercial beer. It's neither easy nor foolproof, but it can be done.