Real Ale (non carbonated) method

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NicB

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If I decant fully fermented beer into a second fermenter (one with a tap neat the bottom).
Then in the head space puff carbon dioxide (which is HEAVIER than air)
Fit a sealed lid with a bubble trap filled with strong solution of sanitiser.
The CO2 blanket should remain intact and move down as beer is drawn out below it.
And with the air drawn back through the reversed bubble trap being sanitised.
Has this method been tried?
Why wouldn't it work?
N¡ck
 
It will work if you drink it in a few days. It will lack the sparkle of a pint of "real ale" which is still carbonated but to a much lower degree (cask beer is usually added to a cask before fermentation is complete which as it finishes carbonates it slightly).

As you draw beer from the tap of the bucket, if you don't then add more co2, you will eventually (maybe 4-5 days) have beer that is passed it's best as air will mix with your beer. People may use cask breathers to prolong the life or a corny keg with a handpump with a co2 line connected and set to a very low pressure. Or something like a king keg where you top up the co2 after each pour. Obviously you could also bottle to a very low carbonation as I do for bitters.
 
As the liquid level falls as you remove your beer you will progressively draw a vacuum, assuming the lid is fully sealed against the FV. At some point the liquid head pressure will be less than the vacuum in the head space and so you will get air bubbling back through the tap when it is opened (or sucked in via the airlock) to balance things out, and your beer will then start to spoil unless you can drink it in a matter of a couple of days. This is what happens to PBs when they lose their top pressure.
 
Completely un carbonated beer isn't nice, though CO2 is heavier it will still mix with the air and for what you seem to want to do a bag in box would be a better solution.
 
The analogy I use to explain this:

Cream is lighter than coffee. If you're careful you can float the cream on the coffee. Voila, "Irish" coffee.

Now stir the cream into the coffee. Wait for the cream to separate out on the top again.

I'll come back in a few days to see how you got on.


The other argument is air is about 0.35-0.40% carbon dioxide. Carbon dioxide is heavier than the other gases in air. So CO2 sinks and that is why there is no such thing as trees :confused: And if you lie down on a beach by the seaside you suffocate o_O



Seriously though. For a well thought out (well I think so!:rolleyes:) way of getting homebrewed "Real Ale" I wrote this up: https://drive.google.com/open?id=0BwzEv5tRM-5EQUhZbDNPdmV1bWc (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.
 
Have you considered a polypin? They are pretty cheap and perfect for real ales. And they collapse as you pour so no oxygen gets in.
 
As Co2 is heavier than air and sinks it should travel down as a blanket and act as a barrier between the beer and the 'sanitised' air drawn backwards through the air lock.
As the beer draw off is relatively slow the level in the container would also drop very slowly (probably less than 1cm based on a container diameter of 350mm).
This would be more laminar than turbulent.
What I'm uncertain of is to what extent the Co2 would be mixed with the air drawn in through the reversed air lock.
Your right I've been looking at the Vigo Bib as an alternative.
The fear that is holding me back is the possibility of a further enzyme fermentation and popping the bag.
Although this risk reduces as the bag (Bib) collapses.
I'm not convinced that this will work but other than the Co2 mixing I can't see how it wouldn't work.
I'd love to hear more opinions.
Here is commercial piece of kit which goes about keeping a blanket of Co2 on top of real ale....
*****
The RLBS Cask Aspirator is a revolutionary piece of dispense equipment which will keep an open cask of ale in premium condition for up to 20 days.

This valve helps control / balance the CO2 contents of the beer in an open cask as CO2 is an essential part of the brewing process of real ale.

A simple explanation on how a cask aspirator works is as follows.

In a non-aspirated cask system, when a pint of ale is pulled from the cask (with handpull system), a pint volume of air (from your beer store/cellar) is pulled into the cask to replace the beer leaving (volume out - volume in). It is the bacterial and wild yeast in this air which instantly starts the process of the ale becoming stale.

The RLBS Cask Aspirator valve is connected to a supply of CO2 beer gas (from you keg set-up or independently).
Up to 8 casks can then be connected to the Aspirator Valve (to the cask vents, spiles or widge valves). Then as a pint of ale is pulled from the cask, instead of a pint volume of air being drawn into the cask, a pint volume of CO2 is pulled in. This CO2 content is balanced by the valve so to not saturate into the beer and as CO2 has no bacteria or wild yeast in its volume means the beer in the cask is kept in premium condition for upto 4 times longer than before.

Another advantage with this system is now you can use a bigger volume cask and be safe in the knowledge you have the extra time this now allows to use all its content.

Now CAMRA (Campaign for Real Ale) recognised

Any thoughts N¡ck
 
Great .pdf peebee I really enjoyed reading it.
N¡ck
 
I tried to find a solution to this a couple of years ago, the only thing you can do bar drinking a full batch of beer within 5 days is catch the co2 from your ferment and pour from your fermenting vessel. As the ale is drawn out the captured co2 is drawn in. I have tried it with the hand pump but it isn't real ale as you are drawing in co2 and not air. When the hand pump draws the beer air is mixed in and air in round figures is almost 80% nitrogen hence a smooth creamy head and mouthfeel.

Fermenting an capturing the co2, I can also do an oxygen free transfer between the two cubes, the gas and the beer changing places so then pouring out of secondary.
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First attempt, without pressure release, I had pressure tested the cubes to 26 PSI before hand and it was the fastest bitter I had ever made, 10 days from pitching yeast to drinking.
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10 days after pitching yeast, there is also a phenomenon with using the co2 from the ferment is it gives a really smooth mouth feel, I have no idea why there are posts on Pro Brewer about the same thing.
 

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As Co2 is heavier than air and sinks it should travel down as a blanket and act as a barrier between the beer and the 'sanitised' air drawn backwards through the air lock.

No. The blanket of co2 thing is myth that really needs to die. As soon as there's any other gas present they'll mingle. Someone said it before - gases don't stratify like that based on their molecular weight.
 
I tried to find a solution to this a couple of years ago, the only thing you can do bar drinking a full batch of beer within 5 days is catch the co2 from your ferment and pour from your fermenting vessel. As the ale is drawn out the captured co2 is drawn in. I have tried it with the hand pump but it isn't real ale as you are drawing in co2 and not air. When the hand pump draws the beer air is mixed in and air in round figures is almost 80% nitrogen hence a smooth creamy head and mouthfeel.

Fermenting an capturing the co2, I can also do an oxygen free transfer between the two cubes, the gas and the beer changing places so then pouring out of secondary.
View attachment 23297

First attempt, without pressure release, I had pressure tested the cubes to 26 PSI before hand and it was the fastest bitter I had ever made, 10 days from pitching yeast to drinking.
View attachment 23298
View attachment 23300
10 days after pitching yeast, there is also a phenomenon with using the co2 from the ferment is it gives a really smooth mouth feel, I have no idea why there are posts on Pro Brewer about the same thing.
I got most of this (I think) and I'd like to try your method... can you give a little more detail on how to separate the trub from the beer under pressure please.
Thanks N¡ck
 
I got most of this (I think) and I'd like to try your method... can you give a little more detail on how to separate the trub from the beer under pressure please.
Thanks N¡ck
You really have no need to as long as it is only the yeast in the bottom of the fermenter. A good floculating yeast will drop out and form a solid base on the bottom of the fermenter, no need to worry about any coming out of the tap. Or just do an oxygen free transfer to a secondary prior to the ferment finishing. If you are going to pressure ferment don't do it until there is only a few points left to go for final gravity.

For transfers to a secondary.
002.JPG

Well worth a read if you are interested. Tried to upload it but it is to long.


Closed System Pressurized Fermentation
by Teri Fahrendorf

http://www.terifahrendorf.com/Closed-Pressurized-Fermenatation
 
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CO2 will pool because it is heavier than air, but this side of absolute zero it wont pool for long as CO2 is very miscible with air (the coffee and cream analogy is nice but not entirely true because a component of cream is fat and that is not miscible with water and it will eventually separate out again). The "death pools" on some volcanos only keep their lethal CO2 "blanket" because the volcano is constantly replenishing the CO2.

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

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.


(EDIT: There is no "other side of absolute zero". That's it, all stop, nothing colder. Temperature is just a measure of things "moving about" and when everything stops moving about there is nothing more to measure.)
 
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You can slowly introduce air on top of CO2 and initially there will be two 'layers'. But over time the two layers will homogenise, even assuming the volume is completely undisturbed by say convection currents . And the warmer the environment the quicker it will happen. Its called Brownian motion. It was identified in the 19th century.
And gases are fully miscible as far as I know. Whereas liquids need not be.
 
The "Vigo BIB" pouches mentioned are virtually impermeable to gases. Unlike standard polypins made of polythene. But I know of people who have had trouble with these "pouches" for keeping beer (delaminating, and so forth).

@foxy's containers pictured above are also polythene (HDPE or MDPE) but very much thicker than polypins so will keep beer much longer. Whatever the container most beer (under 6 or 7%) needs drinking within a few months anyway. One beer I've brewed (a Marsden's Pedigree clone) wont keep longer than a few weeks whatever I put it in (that's to do with very large gypsum additions … I think).
 
It's a good idea, but it won't work. The carbon dioxide layer will mix with the air that you draw in. Gases are fluid and mix with each other. The polypin idea, above, is the best idea so far, I reckon.
 
Sorry to jump on this old discussion, having recently acquired a hand pump, is the general consensus that a polypin is better than a pb with co2 and breather?
 
A "general consensus"? I don't think one of them exists. Have you read the thread?

Just to spark off the "lack of consensus" again:

Polypins impose a short shelf-life (4-5 weeks, perhaps less for some people). PBs are better but you need to mess with CO2. "Breathers" for home-brew are hopeless!
 
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