What happens if you overfill a bottle and don't leave a gap?

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orlando
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Re: What happens if you overfill a bottle and don't leave a

Post by orlando » Sun Apr 30, 2017 7:48 am

By the time a beer has completely fermented out it has consumed most of the oxygen, which is a good thing, as oxygen at this stage is a staling agent and will reduce the shelf life of the beer. However, in transferring the beer inevitably a little O2 is reintroduced, bad thing, but. By leaving a gap there are two benefits, the first is that the yeast has a little O2 to work with (removing in the process i.e. good thing) to produce the CO2 and the gap gives it the space to expand into, eventually being reabsorbed into the beer during the couple of weeks in cold storage. No gap this doesn't happen = flatter beer. :wink:


The other question was about CFC bottled beers. Here the beer has already absorbed the CO2 by either secondary conditioning or force carbonation. Theoretically a gap is not a good thing as the CO2 will come out of solution to fill it, leading to flatter beer.
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f00b4r
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Re: What happens if you overfill a bottle and don't leave a

Post by f00b4r » Sun Apr 30, 2017 6:37 pm

orlando wrote:The other question was about CFC bottled beers. Here the beer has already absorbed the CO2 by either secondary conditioning or force carbonation. Theoretically a gap is not a good thing as the CO2 will come out of solution to fill it, leading to flatter beer.
I would agree that is what I would expect to happen as well but next time I go to bottle more than a couple from a keg I think I will see if the practice agrees :)

Still curious about the colour change though and if it really was related to the head space our just coincidence.

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Jocky
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Re: What happens if you overfill a bottle and don't leave a

Post by Jocky » Sun Apr 30, 2017 8:29 pm

Was the beer with a head appreciably darker, or was it just darker because it was in shadow from the head?

Normally darkening in beer is caused by oxidation.
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orlando
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Re: What happens if you overfill a bottle and don't leave a

Post by orlando » Mon May 01, 2017 6:48 am

f00b4r wrote:
orlando wrote:The other question was about CFC bottled beers. Here the beer has already absorbed the CO2 by either secondary conditioning or force carbonation. Theoretically a gap is not a good thing as the CO2 will come out of solution to fill it, leading to flatter beer.
I would agree that is what I would expect to happen as well but next time I go to bottle more than a couple from a keg I think I will see if the practice agrees :)

Still curious about the colour change though and if it really was related to the head space our just coincidence.

I'm able to do this too so might have a play.

Colour is more of a conundrum. I wondered whether the overfilled bottle had a little more yeast in suspension, thus reflecting just enough more light to make it appear lighter.
I am "The Little Red Brooster"

Fermenting:
Conditioning:
Drinking: Southwold Again,

Up Next: John Barleycorn (Barley Wine)
Planning: Winter drinking Beer

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