• Please visit and share your knowledge at our sister communities:
  • If you have not, please join our official Homebrewing Facebook Group!

    Homebrewing Facebook Group

Carbonation issues when bottling from keg

Homebrew Talk

Help Support Homebrew Talk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dabber18

Member
Joined
Jun 22, 2016
Messages
18
Reaction score
3
I made a batch of stout from an extract kit. Tertiary was keg with force CO2. Yield was bout 48 bottles. Drinking them, the first 24+ were almost perfect in head/carbonation. However, the last 6 to 10 (there are about 12 left) have way to much head. I can only pour about half a bottle (12 oz) into an American pint (16 oz) glass before the head is over the brim and I can't pour more. I even tried drinking from the bottle, but it almost foams out the mouth with anything more than a small sip. I was originally worried that the yeast kept working and I thought it was carbonating the sugars in the bottle, but a friend that I gave a bottle to out of the first 24 recently drank it, and it was still perfect. This would indicate that it is a carbonating issue in either the first or last half of bottles. I believe it is the first half, but I am not positive of this. The flavor is still great, and I tried a wet glass which helped curtail some of the head. Anyone experience an issue even close to this? Any recommendations?
 
If you force carbonated that rules out uneven priming sugar mixing as a source of problems.

A slow infection or beer that did not quite finish fermentation could both be responsible for gushers. In either case, keeping the bottles cold would postpone the problem. Maybe your friend put his bottle in the fridge?
 
The CO2 pressure was set too high for the beer temperature to maintain the desired carbonation level through the life of the keg, and as the remaining volume diminished the carbonation level kept increasing...
 
The CO2 pressure was set too high for the beer temperature to maintain the desired carbonation level through the life of the keg, and as the remaining volume diminished the carbonation level kept increasing...

I had the CO2 on about 12 during carbonation period, I dropped the pressure to about 3 or 4 during bottling. 12 was at the high end for the style temp, but I've had a flat batch in the past and didn't want to repeat that issue either. I don't use a carbonation stone and had it pressurized for about 2 weeks. Do you think shortening the time and using a carbonation stone would help?
 
[...]I don't use a carbonation stone and had it pressurized for about 2 weeks. Do you think shortening the time and using a carbonation stone would help?

If you fitted your keg to use a carbonation stone you could indeed shorten the time it takes for the full keg to reach your carbonation goal. Or just add more patience :)

"Over carbonated" may have been an overstatement on my part. But your early bottles were filled with less carbonated beer - "under carbonated", depending on what you were actually aiming for. And the later bottles were filled with higher carbonated beer - perhaps the exact carbonation level you were in fact aiming for all along.

Bottle and growler filling can be challenging if you don't have your equipment and technique down pat, and the higher the carbonation level the more challenging it can be. I think that's what you proved.

You didn't actually mention how you were filling the bottles. Did you use a gun, some tubing attached to a faucet or picnic tap, or something else?

Chilling everything from keg to bottles and everything in between is a good start, rinsing the bottles in chilled Star San helps reduce nucleation effects, if using a gun or equivalent a really long beer line helps, along with reducing the CO2 pressure...

Cheers!
 
You didn't actually mention how you were filling the bottles. Did you use a gun, some tubing attached to a faucet or picnic tap, or something else?

Chilling everything from keg to bottles and everything in between is a good start, rinsing the bottles in chilled Star San helps reduce nucleation effects, if using a gun or equivalent a really long beer line helps, along with reducing the CO2 pressure...

Cheers!

I used a Blichmann beergun. Bottles were sanitized the day before, and then placed in a freezer. I took the bottles out of the freezer about 20 minutes before bottling. The "flat" bottles were from the previous batch, not the batch in question, and weren't completely flat, just needed a hard pour to get a good head.

I've successfully bottled 2 batches of hard cider, and my brew mentor and I have bottled several beer with the Blichmann (it's his, but he lets me use it).

Thanks for the suggestions and help. I do think I'll look into a longer hose, try chilled sanitizer, and reducing pressure a little more during bottling. I think using your reference, the first bottles were perfect and the last were over carbonated.

Next up, IPA in secondary, hoping it's carbonated to perfection... :mug:
 
The CO2 pressure was set too high for the beer temperature to maintain the desired carbonation level through the life of the keg, and as the remaining volume diminished the carbonation level kept increasing...

Here's what could have happened:
Carbonated at 12 psi
Dropped pressure to 2 - 4 psi to fill bottles.
As the bottles were filled, the level of beer in the keg slowly starting going down, increasing the empty headspace.
With every fill you increase the headspace a little more, which frees up space for more gas.
The headspace is filled with co2, but with the pressure set at 2 - 4 psi, it can't keep 12 psi IN THE BEER.
The pressure wants to equalize, so every time you free up some headspace, a little co2 comes from the tank and a little comes out of the beer as foam, eventually equalizing at 2 - 4 psi leaving you with a bunch of foam and flat beer.
The carbonation would drop slowly as you bottle, which might explain why some seemed good and others towards the end were not good.
If you purged the keg before starting, it probably sped up the flattening process.

After much frustration with my beergun, I applied the line length balancing technique to bottle filling and it is amazing. I leave the pressure at serving pressure and DO NOT PURGE THE KEG before bottling.

Edit: just re-read and noticed that the LAST bottles were over carbonated, so my explanation might not be the answer in this case.
 
Here's what could have happened:
Carbonated at 12 psi
Dropped pressure to 2 - 4 psi to fill bottles.
As the bottles were filled, the level of beer in the keg slowly starting going down, increasing the empty headspace.
With every fill you increase the headspace a little more, which frees up space for more gas.
The headspace is filled with co2, but with the pressure set at 2 - 4 psi, it can't keep 12 psi IN THE BEER.
The pressure wants to equalize, so every time you free up some headspace, a little co2 comes from the tank and a little comes out of the beer as foam, eventually equalizing at 2 - 4 psi leaving you with a bunch of foam and flat beer.
The carbonation would drop slowly as you bottle, which might explain why some seemed good and others towards the end were not good.
If you purged the keg before starting, it probably sped up the flattening process.

After much frustration with my beergun, I applied the line length balancing technique to bottle filling and it is amazing. I leave the pressure at serving pressure and DO NOT PURGE THE KEG before bottling.

Edit: just re-read and noticed that the LAST bottles were over carbonated, so my explanation might not be the answer in this case.

I think you are spot on. Based on my notes and my memory, first of which I know is right, but the second may not be the best, :off: :) , I bottled 47 bottles and started drinking from the non-full case. That would mean that I likely drank the last filled bottles first, and am at the first filled bottles now. I will get the extra hose for my next bottling session.
 
I think you are spot on. Based on my notes and my memory, first of which I know is right, but the second may not be the best, :off: :) , I bottled 47 bottles and started drinking from the non-full case. That would mean that I likely drank the last filled bottles first, and am at the first filled bottles now. I will get the extra hose for my next bottling session. Do you recommend the 25-30 feet like jmcquesten?

I would get 25-30 ft. It seems ridiculous, but try it for yourself. The really long line will make filling a little slower, but will greatly increase the quality of the bottled beer. Just coil it up and zip tie it.

The keys to this are:

DO NOT PURGE KEG - leave it at whatever your serving/carbonation pressure is.

DO NOT LOWER THE PRESSURE - if you carbonate at 12 - 15 psi, leave it there to fill bottles. The long line will slow down the beer enough to reduce foam.

I've found that doing this gives me nicely carbonated bottled beer with minimal foam. You will still have some foam, but not nearly as much. The amount of foam is about the same as what you would get at the top of a pint glass. I know this because I did a "test pour" by filling a pint glass from the beer gun.
 
I would get 25-30 ft. It seems ridiculous, but try it for yourself. The really long line will make filling a little slower, but will greatly increase the quality of the bottled beer. Just coil it up and zip tie it.

The keys to this are:

DO NOT PURGE KEG - leave it at whatever your serving/carbonation pressure is.

DO NOT LOWER THE PRESSURE - if you carbonate at 12 - 15 psi, leave it there to fill bottles. The long line will slow down the beer enough to reduce foam.

I've found that doing this gives me nicely carbonated bottled beer with minimal foam. You will still have some foam, but not nearly as much. The amount of foam is about the same as what you would get at the top of a pint glass. I know this because I did a "test pour" by filling a pint glass from the beer gun.

THANKS! I bought 30 feet of hose for the beer gun, kept the bottling pressure at carbonation pressure (this batch was IPA) and no issues bottling like there would have been with the 10 feet that come in the kit. I've only had two bottles (starting with the last again) and they are great. Next one, I'll have to try from the first bottled, but now I think as long as I have the carbing pressure right, the bottling will be spot on.
 
THANKS! I bought 30 feet of hose for the beer gun, kept the bottling pressure at carbonation pressure (this batch was IPA) and no issues bottling like there would have been with the 10 feet that come in the kit. I've only had two bottles (starting with the last again) and they are great. Next one, I'll have to try from the first bottled, but now I think as long as I have the carbing pressure right, the bottling will be spot on.

Awesome! Glad to hear it's working out for you.
 
Back
Top