Make Cask Ale at Home with Polypins

by Ryan Murphy | Updated: August 15, 2011

Given my love affair with all things English beers, it is not surprising that one of my favorite methods for serving beer is the venerable cask.

That being said, translating cask ale to the homebrewing scene is no simple task.

The most tricky part of all of this is probably the short shelf life of cask ale being only 2-3 weeks once tapped. This means that once tapped you would have to drink 86 pints of beer in that time if you used a Firkin or 46 pints if you used the small Pin. Now for some of you this might not be a problem, however, as I live by myself, it is.

If you are like me and still want cask ale at home, but don’t want to drink 86 pints in 2 weeks there is an alternative, polypins.

What are Polypins?

Polypins simply are square soft liquid containers that come in a variety of sizes such as 1 gal., 2.5 gal., and 5 gal. What makes them great for cask ale is the are flexible, but tough which helps to keep them from bursting when carbonating.

When I first started on this journey to cask ale homebrew, I picked up 3 one gallon polypins from US Plastics. The best part is they are fairly inexpensive so if you happen to overcarbonate one and it bursts, you are only out a couple bucks.

How to Brew Cask Ale

Simple brew like you normally would. Cask ale is purely a method of packaging and serving. Granted you may want to consider what type of beer you are brewing as ales will typically respond better to cask conditioning and serving as opposed to lagers.

That being said, if you want to serve your latest Bock on cask, go for it! Brew how you normally would, ferment as you normally would, then comes the fun part.

Out of the Fermenter, into the Polypin

After fermentation has finished, it is time to break out the polypins.

  1. Clean and sanitize them as you would any other packaging medium (bottles, kegs, etc.).
  2. Calculate your carbonation sugar addition for the l .8-1.5 vol range typical of cask ale then fill your polypins and just like you would with bottles or a keg, leave a little bit of head space in the polypin.
  3. After they have been filled, they should go back to cellar temperatures (52-58F) to carbonate. As they carbonate, the polypins will start to expand and look they are going to burst, vent them 1-2 times, but be careful not to vent them too much or no carbonation will be absorbed into the beer.
  4. After a couple weeks, you will have carbonated cask ale ready to serve and enjoy!

My Results

So far I have done 2 batches of cask ale in polypins with 2 very different outcomes. The first was an English Mild that never carbonated and the second was an English Bitter that carbonated well, but I vented it 1 too many times and it was a touch on the flat side. Even with that there is a huge amount of potential in serving homebrew this way once I have dialed everything in.

The next beer that I will be brewing on to serve in polypins will be a nice English Mild again.

Anyone else attempted homebrewed cask ale?

Ryan has been homebrewing for just shy of 2 years and is in the planning process of starting a nanobrewery. A native of the northern IL farm country, Ryan is currently enjoying the beer and brewing scene of Chicago, IL.