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?
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