A batch of Sierra Nevada Bigfoot Barleywine bubbles and froths in this time-lapse video produced by Sierra Nevada Brewing Company.

The time-lapse was taken over six days showing 12,400 gallons of wort, 1,215 pounds of whole-cone hops, and 1,000 pounds of brewer's yeast in four open-top fermenters.

Very simply, beer is made by extracting sugar from grains and fermenting these sugars with yeast to turn them into alcohol. Wort is the sticky, sweet liquid extracted from mashing grains like barley or wheat. Hops are small, green conelike fruits from a vine plant that provide flavor. When yeast is added to the mix, it eats up all the sugar in the wort and spits out carbon dioxide and alcohol as waste products.  

Bigfoot Barleywine is a limited edition strong ale that Sierra Nevada releases each January.

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