Never considered this before, but is there any value in me letting my NEIPA warm up before bottling? If I transfer it to the bottling bucket and bottle it at its current 34f, I guess it will absorb more oxygen during that process than at a higher temperature… though how much more, I have no idea.
Considering how much lower we have to set the CO2 pressure on kegs for a certain vols of CO2 at (say) 41f versus 53f, the potential for colder beer to absorb gas more easily seems clear, but I haven’t seen the issue discussed. Maybe I’m missing something.
Here’s a pro to bottling cold beer. The cold beer holds more CO2, which is released as the beer is transferred to a warm bucket and warm bottles providing more of a blanket effect than warm beer. I don’t know if the pros or cons win ultimately.
Right, but where would this extra co2 come from? If crashing, little if any co2 is produced as fermentation is done. If crashed in a keg with some head pressure your idea is gold.
I still don’t think it’s better unless one can ensure the gases dissolved while crashing is co2. If cashing there is no point in letting it warm, but it’s false to say that the gas coming out while racking to the bucket would add any protection.
Even “still” beer post fermentation contains between 0.75-1.0v/v CO2. This will constantly but very slowly be evolving, faster as it warms up. Bottling cold beer into warmer bottles and letting them stand a while before capping should maximize the CO2 that comes out into the headspace.
For example: assume beer is at 65F at the time it finishes fermentation. It has X dissolved CO2. Then you chill it to 32F. It still has X. But if you warm it above 65F it will have <X dissolved CO2. Then if you chilled it again to 32F, it still has <X dissolved CO2.
Based on my fishing experience, I’m quite sure that if you have X oxidation from air in contact with beer at 65F, that you will get >X oxidation if you drop the temp 32F and leave it in contact with air.
I think you’ll need pressure or more sugar to get more disolved CO2 though.
But air is what, 70% nitrogen? So maybe if you expose it long enough it would work for a Guiness draught? [emoji41]
Cold beer warming up will release CO2 during transfer and bottling, which makes sense, which, may provide some sort of blanket (though some of what is released is presumably what has been absorbed from the air, not just CO2). Hope I got that right. I guess that the cold beer will have reached a point of equilibrium with the atmosphere by the time of transferring and bottling, so my question as to whether it will absorb more air than warmer beer at that time is moot; it can’t absorb any more (without chilling further). So potentially some upside to bottling a cold beer in warmer vessels, but none in warming it up first.
As a side note, despite selling my keg equipment last summer, I still have a 7Kg gas bottle, which I have been able to use on its own to purge the headspace of the secondary a few times. Not a precise operation, but seemed worth doing. I will purge the bottling bucket too, as best I can, and maybe even a few of the bottles going in a competition!
I keep running this through my head, and something still puzzles me: if a beer has finished absorbing X amount of CO2 and anything else from the head space at a given temperature, at atmospheric pressure, then why do we consider transfers into new vessels to be such an oxygen risk? Doesn’t it follow that it can’t pick up more oxygen or anything else from the air, unless the pressure or temperature changes?
Ideally, when done the beer will have more CO2 than is in air and no O2 at all. So left open to the air, O2 will equalize by entering the beer and CO2 will equalize by leaving the beer.
Pressures not percentages… beer will never be 70% nitrogen.
OK, I think I get that. 8) So while there may be an overall equilibrium in pressure, the increased interface with the air during a transfer can speed up the rate that the proportion of gases in the beer start to match those in the air. And with that being nearly 21% oxygen and only 0.04% CO2, that’s bad news. I’ve learnt something today, thanks.