Fermentation

Less than 24 hours later and fermentation has begun on my Dunkelweizen. Fermentation occurs when yeast begins to convert the sugars present in the wort into alcohol, thus creating beer. The tan / white foam on the top of the fermenting wort is called a Krausen -

During the first few days, the Krausen on a beer can fill your fermentation vessel to an extreme amount. Often times a carboy doesn't have enough space to contain the Krausen and if not properly directed elsewhere through a blowoff tube, your beer will explode all over leaving a huge mess. Always use a blowoff tube even if you think you won't need one - 

Fermentation can take anywhere from 10 days to up to a full month depending on the beer style. Once the specific gravity on a beer doesn't change for 3 or 4 consecutive days, your beer is done fermenting. However, as a rule of thumb, I always leave my beer in a single fermentation vessel for at least 3 weeks to let the yeast fully finish its work.

It's also one of my favorite things to watch while brewing; fermentation is very active usually and is one reason I like to brew in see-through containers to observe it -

Brew on!

Ryan