Steamworks Brewing Co. continues its monthly Firkin Friday, introducing Caramel Apple Firkin.

“The base of this firkin is our award-winning Steam Engine Lager, which already has a caramel flavor component derived from the malt,” said Ken Martin, Steamworks head brewer. “Then we added two gallons of fresh, unfiltered western slope apple juice and a little more caramel flavoring. The flavor and aromas of our trials were just what you’d expect – just like a caramel apple!”

A firkin is an old English unit of volume, typically a wooden cask equal to approximately one-quarter of a regular barrel, or nine gallons. Steamworks initiated its Firkin Fridays to introduce a range of specialty craft beers not suited to large draft production. Each month an unusual brew is tapped, coordinated with the season or holidays.

Firkin beer is unpasteurized, unfiltered and naturally carbonated, or conditioned, it its cask. The yeast transforms the sugar into alcohol within the cask, and carbonation results from the trapped carbon dioxide occurring as a byproduct. Because it's gravity-poured, a firkin beer requires a special tap.

"And remember that a firkin is served at about 55 degrees - cool but not cold," said Spencer Roper, Steamworks assistant brewer. "Because it contains no preservatives, it's also designed to be consumed after tapping, which thus far hasn't been an issue. Come early to make sure you get a pint."