A flavorful brew is contained within this cask with a unique name – firkin.
“It’s kind of like a keg but it doesn’t have the same way of pouring it, so it’s basically a vessel for holding beer, but it’s traditional,” said Ken McMullen, the Brewmaster at Hopvine Brewing Company in Aurora.
The process to create a cask ale, like that in a firkin, is the same as brewing craft beer, up until the final steps.
“We’re coming out of one of these the yeast is still somewhat in suspension, adding a little sugar, and then filling the firkin and closing it up. Then the yeast gets active again, it gets those sugars, a little more alcohol and then the CO2 and then it carbonates itself,” said McMullen, who has been a brewer for over 20 years.
The tapping and pouring process is also unique, and contributes to its rarity as the beer in a firkin will go bad after it has been open for just a few days.
McMullen explains, “when you pour a firkin, you’re pouring it via gravity, so what replaces the beer is air. Air oxidizes beer, it’s basically what makes beer go stale.”
While its shelf life isn’t long, the flavor contained within is smooth and distinctive to each batch.
“It’s a little smoother carbonation so you get a smoother mouth feel,” said McMullen. “It’s also, the beers alive it’s not filtered. There’s still yeast in it so your first taste of a firkin is going to be different than a taste in the middle and a taste at the end. So it’s one of the cool things about a firkin is it evolves as you drink it.”
And if you want to find out for yourself, dozens of area brewers will be bringing their take on the firkin to the first ever Naperville Firkin Fest in September.
A firkin typically contains about 70 pints of beer.
Naperville News 17’s Evan Summers reports.
