Cask, Firkin & Pin - What's in a name?

Pin and Firkin Casks
photo courtesy of Flickr user cizauskas

The first 'What's in a name?' post I did about the meaning of the name "Grand Cru" seemed to be pretty well received, so I thought I'd expand this idea and explore more beer world lingo that may throw some for a loop. I thought next I'd provide some explanation of the terms firkin, cask and pin. Now many of you seasoned beer drinkers probably already know the difference between these terms, but as more and more events around town seem to be celebrating and utilizing these smaller beer vessels, it seemed appropriate to detail their differences.

To start with, let's clarify this; when you hear the word 'cask' referred to, it is an inclusive word that doesn't immediately tell you anything about the size of the actual beer vessel, but just makes reference to the fact that it contains cask-conditioned beer. So when you hear that a bar is tapping a cask of something, they are likely tapping one of two different sizes of cask, and those are referred to as a firkin or a pin.

Firkin is probably the most typically seen/heard of these two sizes around these parts (Mother's Firkin Fridays, anyone?), and in general, is the most common cask ale container. Cask ale, you say? Okay, maybe it's time for a brief history lesson. The firkin, a word which is based on the Middle Dutch word vierdekijn, meaning "fourth", actually dates back to the mid-15th century as an ale vessel. Historically, firkin beer (and cask beer in general) differs from the standard keg beer we are familiar with because it is not injected with carbon dioxide and pressurized. Rather, firkin beer is unpasteurized and naturally carbonated/conditioned inside the firkin itself through the use of active yeast. Also, it is typically served at a slightly warmer temperature than standard kegged, chilled beer to allow for this yeast to stay active and keep the beer carbonated. In terms of size, a firkin is equal to 9 imperial gallons, which is 10.8 US gallons, which ends up being approximately 86 16-ounce pints worth of beer.

Pin is a word that you generally don't hear too often, probably because it's not as marketable and fun to say as 'firkin.' A pin is a smaller cask size, essentially a half-firkin. It holds 4.5 imperial (UK) gallons, which is 5.4 US gallons, which ends up being approximately 43 16-ounce pints worth of beer. If a bar refers to a cask that they are tapping without specifically mentioning a firkin, there's a chance it is this smaller pin cask. As an example, the recent Odell IPA cask at Brewbaker's was a pin, and from what I hear, was empty in about 20 minutes. I personally hope that more bars will start specifying if their casks are firkins or pins, so people can get a better idea of just how much beer there will be to go around.

So let's give all this a quick, basic rundown:

• A cask is a vessel that contains unpasteurized beer that is naturally carbonated through the use of active yeast inside the cask.

• You'll typically see casks come in two sizes: firkins and pins.

• A firkin is equivalent to 10.8 US gallons, or about 86 pints.

• A pin is equivalent to 5.4 US gallons, or about 43 pints.

So there you go! Next time you see a beer event that involves a cask being tapped, you can walk in well-educated. And if they don't specify whether it's a firkin or a pin, harass them about it. And even more importantly, if they are pouring from a standard, chilled keg and referring to it as a firkin, physical violence may be necessary. Okay no, not really. But definitely more verbal harassment.