Naturally carbing with no headspace at all?

[Tippyman]

I currently keg in 1/6 bbl Sankey kegs. I use a standard coupler with the check valves removed to fill via gravity. I use a funnel to add the water/priming sugar solution first, then rack the beer on top until it pours out of the gas in line. Thus I have a completely full keg with no headspace and no air inside.

I haven't really been getting good carbonation. I usually have to do some 30 psi rocking when i put it into the kegerator before it's carbed enough to drink. I'm letting the kegs go two weeks at room temperature. Is the lack of headspace affecting it? Or does it just need longer than two weeks?

In case you're wondering why I naturally carb, I'm trying to save space in the kegerator and also not buy another coupler and tank to carb with.

Any ideas?

 

[doug293cz]

I can't think of a reason why lack of headspace should prevent carbonation.

How much priming sugar are you using and for what volume of beer?

I would try giving the kegs at least 3 weeks to carb at 70°F. Longer if the temp is lower, or if the beer is more than about 6% ABV.

Brew on

 

[day_trippr]

Unless one believes that all of the CO2 produced by the yeast is fully absorbed in the beer before it reaches the surface, head space matters...I think...

Cheers!

 

[doug293cz]

Unless one believes that all of the CO2 produced by the yeast is fully absorbed in the beer before it reaches the surface, head space matters...I think...

Cheers!

The CO2 is created in solution. Why would it come out of solution if there is no headspace at a lower CO2 partial pressure than the equilibrium partial pressure for the current carb level and temperature?

On another topic, did you finish your popcorn?

Brew on

 

[day_trippr]

Yeah, the more I thought about it the more it didn't make sense.
Exogenous CO2, sure, it applies, but endogenous, not so much.

As for the popcorn, I got two paragraphs in and felt my brain seizing up

Cheers!

 

[Tippyman]

How much priming sugar are you using and for what volume of beer?

I use 2.5 oz with a full sixtel. (5.16 gal)

According to beersmith, that should get me 2.6 vols at 74*. However, after two weeks and then sitting in the kegerator overnight at serving pressure, the carbonation just isn't enough. You think it just needs more time?

 

[EarthwormJim]

That doesn't sound like enough sugar to me. Just bottled yesterday and Northern Brewer's calclator had me add 4.8 oz to 5.5 gallons to get 2.4 vols at 73 degrees. Didn't put your numbers in a calculator, just seems low to me based on what I just did.

 

[Bullshivit-brew]

After putting priming sugar in are you hitting the keg with some co2? My last keg I put 3oz dextrose then hit with 20psi c02 and let carb 2 weeks. It got me close. Cold crashed with co2 set at 10psi and it was good 4 days later.

 

[doug293cz]

I use 2.5 oz with a full sixtel. (5.16 gal)

According to beersmith, that should get me 2.6 vols at 74*. However, after two weeks and then sitting in the kegerator overnight at serving pressure, the carbonation just isn't enough. You think it just needs more time?

2.5 oz of table sugar (sucrose) will create 0.94 volumes of CO2 in 5.16 gal of beer. 2.5 oz of corn sugar (dextrose mono-hydrate) will create 0.82 volumes. Beer that finishes fermentation at 74°F will have about 0.77 volumes of residual carbonation. So, if you used table sugar, your carbonation level would be about 1.71 volumes, and if corn sugar 1.59 volumes.

To get 2.6 volumes with table sugar you would have needed about 4.85 oz, and with corn sugar you would have needed about 5.6 oz.

Brew on

 

[Tippyman]

Beersmith states that when kegging you need a much smaller amount?

 

[doug293cz]

Beersmith states that when kegging you need a much smaller amount?

That is a common misconception in my opinion. I can find no basis in physical chemistry that would support that. I have asked on HBT, and no one has been able to offer any justification why a big bottle (keg) would require less sugar per gal of beer to carbonate than regular bottles. And, no it has nothing to do with headspace. A corny keg with 5 gal of beer has about 6% headspace as does a correctly filled 12 oz bottle.

Your experience says that the idea that a keg requires less priming than bottles is wrong.

Brew on

 

[Brentk14]

Not to talk you out of carbing the way you are, but here's my input. I also keg in sankes. My kegerator has to taps, so two couplers. Even if I have two beers on already, it is really easy to disconnect one, hook it up, bump up the pressure to 25-30 depending on how carbonated I want it, and then disconnect it. I usually toss it into my spare "lager" fridge from there, but when I am ready to tap it, it is usually perfectly carbed, or close.