Increase carbonation after bottling

[jbaker9]

Hi,

I bottled a Best Bitter about a week ago. Yesterday tasted it and there is almost not carbonation.

Prior to bottling I cooled to 10C for a few days. According to Beersmith I would get 1.5vol CO2 with no bottling sugar. I figure since I didn't add any extra fermentable the carbonation is unlikely to increase from what I have now.

I am planning to cool the bottles to 10C, pop the caps, add either 1 carbonation drop into 750ml bottle or some dextrose syrup measured out with a syringe.

Any thoughts on this? I would like ~ 2.0 vol CO2.

Regards
James

 

[manticle]

If you added no sugar and you are certain fg was reached, then calculate the dose required, mix up a solution and syringe each bottle, then recap, warm to room temp and leave to carbonate.

Dry sugar addition will fizz, syringe will be less messy and more accurate.

 

[mtb]

According to Beersmith I would get 1.5vol CO2 with no bottling sugar.

I'm confused as to how/why BS advised you'd get any carbonation if you'd already reached FG and bottled without extra sugar.. am I missing something here?
Also in my experience, a carb drop doesn't cause fizzing. It is an easily controllable dose.

 

[Coalminer]

James, what temperature did you ferment at. That calculator uses the highest temperature the brew got to,, not the lowest

 

[Dan Pratt]

The absorption of Co2 from the headspace into the beer during cold crash is heavily debated.

I believe it happens after many overcarbonated beers which had FG acheived and calculated dosages for desired carbonation.

The amount of CO2 in the headspace is unknown before the cold crash.

No harm opening them and adding a drop or syringe mix and recapping them.

 

[jbaker9]

Hi Coalminer, I fermented at 18C, increased to 21C after fermentation finished then crashed to 10C. It looks like my assumption was wrong.

So.... Regardless of the cold crash temperature at time of bottling I should use the highest temp reached during fermentation?

I did a quick check on brewer's friend calculator... at 21C with no added sugar should give 0.85vol.

My beer fizzed a tiny bit when I opened. There was a thin, broken head on the beer which was completely gone after a few minutes.

 

[jbaker9]

Another question... do I bother chilling bottles before opening, or just open at storage temp (16-17C)?

 

[Dan Pratt]

At storage temp.

 

[Rocker1986]

The amount of CO2 in the headspace is whatever the volume of the headspace is; since the fermenter is not airtight this gas is not under any pressure once fermentation stops. If you had 25 litres of beer and 5L of headspace you'd have 5 litres of CO2 which is probably mixed with some air anyway especially if dry hopping was done, and even if the whole lot was re-absorbed during a cold crash which is unlikely due to there not really being any pressure to force it back in, you'd still only be increasing the carbonation by 0.2 volumes at the most.

My experience with cold crashing and priming beers at a rate based on the highest temp the beer got to has backed that up. Not once did I have an over carbonated batch.

 

[jbaker9]

Thanks for the feedback... I have an oatmeal stout that I carbonated based on the 10C cold crash temp.

Cheers
James

 

[manticle]

I'm confused as to how/why BS advised you'd get any carbonation if you'd already reached FG and bottled without extra sugar.. am I missing something here?
Also in my experience, a carb drop doesn't cause fizzing. It is an easily controllable dose.

If you drop dry sugar into beer (as opposed to into the bottle first) it will often gush.

As to the first - residual CO2 can remain in the beer post fermentation which is how the calculation (not suggesting it is necessarily accurate) would be explained.

 

[mtb]

If you drop dry sugar into beer (as opposed to into the bottle first) it will often gush.

As to the first - residual CO2 can remain in the beer post fermentation which is how the calculation (not suggesting it is necessarily accurate) would be explained.

I drop carb drops into my bottles after filling, no gush. Maybe I'm not dropping hard enough :lol:

Residual CO2, makes sense but I never thought there could be enough to carbonate the beer - unless you fermented under pressure.

 

[jbaker9]

I normally wouldn't mess with individually carbonating bottles... only do bulk priming.

Another question... how much CO2 will be released by popping the top off an undercarbonated beer?

 

[Grott]

I'm lost, you make a decent brew and potentialy stuff it up with some carbonation method that needs calculations beyond just putting in carbonation drops, other normally measured sugar types or bulk prime to known measurements.

Each to their own but I'm not sure why all the trouble.

 

[Killer Brew]

If you added no sugar and you are certain fg was reached, then calculate the dose required, mix up a solution and syringe each bottle, then recap, warm to room temp and leave to carbonate.

Dry sugar addition will fizz, syringe will be less messy and more accurate.

+1 for the syringe method. Have used it once on an undercarbed batch of porter (miscalculation) and gave a very consistent result.

 

[manticle]

I drop carb drops into my bottles after filling, no gush. Maybe I'm not dropping hard enough :lol:

Residual CO2, makes sense but I never thought there could be enough to carbonate the beer - unless you fermented under pressure.

Fair enough. I can't negate your personal experience - mine (at least with dry loose sugar) and that of others is that nucleation points are created and gushing can occur. If that doesn't happen to you, I'd say it's a good thing and you need drop neither harder, nor softer. I still think a syringe is a better way for this particular instance and when I have recarbed undercarbed bottles (yonks ago) that's exactly what I did.

 

[Lyrebird_Cycles]

FWIW I calculate residual [CO2] as 85% of the equilibrium value at the temperature at which the ferment finished and find that this gives accurate results.

The 15% accounts for losses when racking, mixing and bottling the beer. I started with a value of 10% for losses and consistently ended up about 0.2 g/l low, 15% has worked better.