Steamworks Brewing Co. plans to continue its Firkin Fridays series by tapping its “Pineapple Express” firkin at 3 p.m. Friday at its downtown brewpub.

For this firkin, Steamwork’s brewers started with a base of the Sultan of Stoke, the brewery’s New England style or juicy IPA.

“These IPAs are known for their low perceived bitterness and are big on flavor and aromas of tropical fruit,” said Head Brewer Ken Martin in a news release. “We added a pineapple puree to the firkin, which should complement those flavors nicely. Jimmy Buffett would be singing about this one.”

A firkin is an old English unit of volume, typically a wooden cask equal to approximately one-quarter of a regular barrel, or nine-tenths of a gallon. The word “firkin” is derived from the Middle Dutch word “vierdekijn,” which means “fourth,” as in one-fourth the size. Firkin beer is unpasteurized and unfiltered, contains no preservatives and is served at cellar temperature – cool but not cold.

Steamworks, 801 East Second Ave., began its Firkin Friday series to introduce unusual, specialty craft beers to patrons and augment its regular offerings.

For more information, visit www.steamworksbrewing.com or call 259-9200.