Unpressurised conditioning?

[Kev888]

Hi all,

These days I force carbonate some time before serving, and so essentially the carbonation has become a separate thing to (or at least a separate part of) conditioning the beer. So I'm wondering if the long conditioning stage now actually needs to be done under pressure or not - i.e. does the beer just need to rest free from oxygen and at the right temperature to condition, or is pressure and/or dissolved Co2 still important to the process?

Cheers,
Kev

[Blackjack]

Hi all,

These days I force carbonate some time before serving, and so essentially the carbonation has become a separate thing to (or at least a separate part of) conditioning the beer. So I'm wondering if the long conditioning stage now actually needs to be done under pressure or not - i.e. does the beer just need to rest free from oxygen and at the right temperature to condition, or is pressure and/or dissolved Co2 still important to the process?

Cheers,
Kev

Well! I thought beer had been conditioning in unpressurised vessels since time immemorial. In tanks and in casks. Fermentation is usually finished, or almost so, so the partial pressure of CO2 on top is not hugely significant.
Air/O2 ?. dunno. Brewers have always tried to minimise this but some always gets in even if only a little and I think it is generally recognised that this small unavoidable air is part of the conditioning process. The partial pressure of this air is also low so NO pressurisation is not needed. And I have always understood conditioning to be something done at a cool temperature but with no tightly set limits. High pressure CO2 is simply an aid to serving and carbonation if you prefer your pint that way.

[Kev888]

Thats interesting, and kind of what I was thinking too. I understand that cooling helps settling and that the yeasty beasties carry on working for a while 'cleaning up' after themselves (and I think Chris mentioned that in fact force carbonating too early can inhibit that) but i can't see any reason why pressure would be needed in the conditioning stages unless as a by-product of having to prime naturally before all the yeast fell out of suspension.

I don't really understand the Co2 vs oxygen thing either actually, as I once firmly believed the Co2 pressure in the pb kept oxygen from moving in, but apparently not as the oxygen can move through the Co2 anyway, pressurised or not...

Cheers
Kev

[Blackjack]

Thats interesting, and kind of what I was thinking too. I understand that cooling helps settling and that the yeasty beasties carry on working for a while 'cleaning up' after themselves (and I think Chris mentioned that in fact force carbonating too early can inhibit that) but i can't see any reason why pressure would be needed in the conditioning stages unless as a by-product of having to prime naturally before all the yeast fell out of suspension.

I don't really understand the Co2 vs oxygen thing either actually, as I once firmly believed the Co2 pressure in the pb kept oxygen from moving in, but apparently not as the oxygen can move through the Co2 anyway, pressurised or not...

Cheers
Kev

Gases!. Gases mix very well so...generally speaking! heavy gases do not sink to the bottom and light gases to the top. If that was the case the bottom of the atmosphere would be all nitrogen and the top all oxygen.

Atmoshperic pressure is 14 psi and O2 is 20% of the makeup so the partial presssure of O2 is 2.8 psi in loose terms. Look at the overall pressure and the proportions of different gases and there you have it dead simple.

WE NEED TO MUCK ABOUT LESS WITH OUR HOME BREWS
Some processes suit large scale and some suit small scale like what we all do
Commercial breweries might have 20,000 litres of ale in a tank with a surface area of 7sq mts. we might have 1,000 times less but still with a surface of 1/5th of a sq mt. So we need to be much more careful than a commercial brewery, not silly nitpicking but just a bit smarter and use appropriate practice.

transfer as few time as possible. Keep ullage to a minimum. Keep it cool. Do not agitate the beer.
eg. Use an FV with a low set valved outlet rather than a siphon. Rack straight fronm the FV into whatever your preferred barrel is pb/cask/corny seal for howver long for conditioning and then serve directly under a low pressure blanket of CO2 eg. an S30 cylinder or a CO2 bottle and cask aspirator.

[Kev888]

Hmm, yes I can see theres definately stuff to consider in there.

I'd initially been planning to use the large PET betterbottles for cooled conditioning and storage, ideally though I'd use bigger plastic barrels. Neither would be pressurised, and whilst the PET bottles are quite impermeable to oxygen (and so better for long term storage) I can't see why the barrels would be any worse than normal PBs 'unless' the pressure itself makes a difference to conditioning or storage.

Cheers,
Kev