Polypin vs. Cask

[Rmr9]

Hello all,

I’m gathering all the materials I need to build a nice setup to use with my beer engine that I scored off eBay. I brewed one batch of bitter and used a polypin to serve out of and it went pretty well, but it eventually went south at about 3 weeks post tapping. Herein lies my question... which would have a longer shelf life once tapped: a polypin or a cask with cask breather attached?

 

[foxy]

You might get some ideas off this thread, I use different size cubes as a cask, ABV dependent.
https://www.thehomebrewforum.co.uk/threads/draught-beer.81405/

 

[Andrew Elliott]

Why not pull it out of a corny keg with a demand valve on the beer engine. I sometimes buy cask from a local brewery and always keg it into 2 cornys unless we expect to drink it at a party. It lasts months once it's under CO2. The key is not to carb it just use the CO2 to replace the volume of liquid you pump out.

 

[foxy]

Why not pull it out of a corny keg with a demand valve on the beer engine. I sometimes buy cask from a local brewery and always keg it into 2 cornys unless we expect to drink it at a party. It lasts months once it's under CO2. The key is not to carb it just use the CO2 to replace the volume of liquid you pump out.

That is what is discussed in the Draught beer thread.

 

[Andrew Elliott]

That is what is discussed in the Draught beer thread.

Sorry me being dim, I didn't see that thread

 

[peebee]

Hello all,

I’m gathering all the materials I need to build a nice setup to use with my beer engine that I scored off eBay. I brewed one batch of bitter and used a polypin to serve out of and it went pretty well, but it eventually went south at about 3 weeks post tapping. Herein lies my question... which would have a longer shelf life once tapped: a polypin or a cask with cask breather attached?

In an earlier post I wrote the following which pretty much covers what you've said, although I do relent and suggest polypins have a shelf life of 5-6 weeks, only because some people will argue if I put 3 (but like you, I find 3 weeks is about maximum shelf life, but I can't believe "post-tapping" makes any difference as beer in polypins is subject to change the moment it is in the polypin).

Consider the following snip from CAMRA's publication "Cellarmanship" by Patrick O'Niell:

It clearly states 1.1 "volumes" of CO2 is optimum conditions for cask ale. Unfortunately it also suggests 1.1 volumes will be sustained at atmospheric pressure: It wont, atmospheric pressure will only sustain about 0.9 v/v (saturation level at atmospheric pressure) so claims of aspirators (or "breathers") keeping beer fresh for "20 days" is pushing it a bit. About 2PSI of CO2 will sustain 1.1 v/v (assuming a 100% CO2 atmosphere in the cask).

I support use of polypins, but polythene is permeable to gases so they do subject the beer to a limited shelf life of about 5-6 weeks - no good if you want to keep a number of beers or have a brewery that can only output a minimum of 40L at a time.

And for my "treatise" on the subject:

For a well thought out (well I think so!) way of getting homebrewed "Real Ale" I wrote this up: Cask Conditioned HB - Final.pdf (Oh Gawd, not that again!). It's on my Google drive 'cos it is too big to post on this site. Not for the (CO2) squeamish.

[EDIT: Some other potential hints, but after two years things have moved on a bit now : Bar Build]

 

[Rmr9]

Hey everyone,

Thanks for the links and thoughts. I’m in the “prioritizing” stages of figuring out which is the best path to go that’s the most cost effective. Cask breathers are really expensive here, I was thinking of picking one up from eBay from someone in the UK or maybe a company based there. It would be great to be able to keep a corny under CO2 at atmospheric pressure.

I have a larger 19L polypin and a couple 4L ones as well. Plus a 3 gallon keg so maybe I’ll have to do some experimenting to see which works best!

I was wondering about using a cask instead as I was able to find a manufacturer in the US that sells them for the same price as a new corny, so I thought getting an upright extractor with the cask breather would be pretty cool.