After reading numerous posts on here about naturally carbonating in a corny keg with priming sugar or another sugar source, I decided to jump in after some research. I bought a spunding valve to watch for pressure, primed the keg with dextrose and sealed her up. I used 5 ounces dextrose in a 5 gallon batch. It has now been 7 days after I sealed the keg with a little Co2 to check for leaks, no leaks. Storing at room temperature right now about 72 degrees F. The gauge so far has moved up about 4 psi in a week to 14 psi. What type of pressure should I expect after a week?, 2 weeks ? 3 weeks? Any help or tips would be appreciated. I also primed to have 2.5 volumes of Co2 in the beer from a carbonation chart, as I understand that carbonation is carbonation no matter the type or source. West coast IPA 8.5 ABV.
You should see about 30 psi at that temp for 2.5V. Give it another week.
i am new to kegging, but to me it makes sense to:
- transfer beer into empty keg (purge or not - tbh I did not - rationale: i intended to see how it worked without purging before deciding if i wanted to purge with co2 in the future)
- add small amount of boiled sugar water to keg to reach low CO2 Vol of ~1.5 say
- Leave at room temp for 7 to 10 days while burping gas valve every 2 days to remove(?) O2 and CO2 (do i need to do this step?)
- move to kegerator and let chill, either attach to gas system and tap or let it sit.
This seems like it could provide beer that lasts better than just beer added directly to gas and tap at cold temps after transfer to keg? minimal effort, no extra equipment involved too.
Does it make a difference? let me know if im missing a step or anything
reason for low CO2 vol of 1.5 is i don’t want to get beer pushed back out through gas quick disconnect.
Part 2 - Please let me know your thouughts on carbing a beer in a keg to a higher CO2 vol ie. estimated for a belgian at 3.0+ or so. In this case could I serve it by simply naturally carbing it with a larger calculated amount of sugar syrup at packaging and then NOT attaching the gas QD, and just attaching it to the tap output?
Thanks
I thought about 28 to 29 but it sure is slow to get there, I am a little worried but not too much. I am trying to be patient like I do with bottles but I have always forced carbed my kegs prior to this point. I am guessing that the amount of headspace has a little to do with it and the slow conversion to Co2 from the priming sugar and yeast.
I would want to monitor the C02 while it is carbing naturally. I am using a spunding valve with a regulator gauge and pressure diaphragm. I used the carbonation chart to decide the amount of dextrose to use, it is going to be it seems a long project to get to my desired pressure. 
Take this with a grain of salt as it has been over a decade or more since I “kegged” and naturally carbonated. I did not use a spunding valve. I carbonated using 1/4 to 1/3 cup table sugar. Left it for a week and a half then vented the keg and served. I adjusted my line length and regulator to get the CO2 level needed.
In summary carbed to an unknown volume of CO2 vented then set the regulator based on line length, temp and co2 volume I wanted. From what I remember I did not have any issues
In fact I do basically the same thing with my “cask” setup. Carb using 1/4 cup table sugar. Start venting after about 3 days. Serve after 1 week and let my cask breather vent excess co2 while adding “blanket pressure” via the cask breather when I pull my beer out using my engine
Don’t over think it
Edited to clarify 3rd paragraph
I’ve naturally carbed my kegs for many years. Like HUEBrewer said, 1/4 to 1/3 cup sugar (I use Corn Sugar but Table Sugar works the same),seal it up with a shot of CO2, and then stick the keg in my storage cabinet until needed. I don’t do any venting until I’m putting it on tap. I have 4 taps on the kegorator so having one off-line for awhile isn’t a problem. I also have 14 kegs so time isn’t generally a big either.
One issue I have been seeing quite a bit for the last 12-14 months is kegs getting seriously over carbed. I changed to dry yeasts around that time due to supply issues and I’m still getting a handle on the new (to me) strains. To avoid beer getting into the gas line I turn off the line to the keg, attach the beer out line and let it cool down to fridge temp. Once it’s cold I pull a sample and see where I’m at on pressure. Too high and I vent a couple times a day until it calms down. If too low I turn on the gas line and let it sit for a few days to even out to serving pressure.
Hope this is helpful.
Paul
Thanks Paul, I am being patient but i don’t think it is ever going to get to 28-30 PSI on my spunding valve gauge. even if it doesn’t I plan on doing exactly what you described to get it right. Cheers!
I should mention when I prime in the keg the table sugar is mixed with about 1/2 cup water and brought to a boil. I simply fill the keg on top of that.
I used to use corn sugar but switched to table sugar two decades or so ago as I always have table sugar around.
In my opinion and experience, its not necessary to have enough sugar or extract left in the beer to carbonate to the full CO2 volume if you’re carbonating in a keg. All you need is enough extract and yeast activity to consume all the oxygen that might have made it into the keg and beer with any transfer. That’s the point to natural carbonation.
Since I use a Tilt, I like to monitor FG progress and transfer when I think that there’s still a bit more fermentation activity left. I seal the keg and keep it at room temp for several days and check it at the end to make sure that the keg did pressurize in that time. Then I hook up the gas line and carbonate as usual (say a quick shake at 30 psi followed by a week or two at normal serving pressure).
Good point on dissolving in water. I forgot to mention that step.
Paul
yes I boil water and add the corn sugar and then let it cool a bit then dump it in the corny keg then transfer the beer and it mixes well.
I find that higher gravity beer in bottles can really take 3 weeks to hit their full carbonation, and that kegs are no different. This is without adding fresh bottling yeast and keeping around 70F. Like was mentioned before, don’t overthink it. A spunding valve is for spunding with residual extract, and isn’t necessary when priming after fermentation is complete. Measure the right amount of sugar for the volume and give it time and it will hit the correct carbonation just like bottles do.
Paul
Very good advice regarding disconnecting the gas in line. I do the same with my cask setup and don’t connect the line until some (4 pints or so) are gone or I am starting to pull on a vacuum
Use the same amount of priming sugar as you would use for bottling.
I brewed 6 gallons of cream ale and put them in two 3 gallon kegs. Checking the pressure after two weeks the keg with the full sugar the PSI was where the chart said it was to be. The other keg was at half the pressure.
As you can see it really does not matter all that much when kegging
Under carbonated, add external CO2. Over carbed, bleed off pressure. Naturally carbonating kegs is very forgiving
Gotcha, Mine is sitting pretty steady at 17 psi for the last two days, I am just going to let it do its thing for about 3 weeks total and make CO2 adjustments from there and enjoy the West Coast IPA!
Hey, sorry but to ask again - in case someone has thoughts on this:
Please let me know your thouughts on carbing a beer in a keg to a higher CO2 vol ie. estimated for a belgian at 3.0+ or so. In this case could I serve it by simply naturally carbing it with a larger calculated amount of sugar syrup at packaging and then NOT attaching the gas QD, and just attaching it to the tap output?
Would this work to consistently push the beer out of the tap, or would CO2 dissipate(?) and reduce after say half the keg is done and youd be serving flattish beer after a bit?
Prior to me setting up my corny cask system I basically did this exact thing
I did not have a fixed tap but used cobra taps. I used the carbonation in the keg to push the beer out. At the time I did not have a CO2 tank so I used small co2 cartridges. Basically I had to hit the keg with a burst of co2 to continue flow. Since I did not have a draft tower I did not have that extra height to deal with
What I predict will happen is you will loose the ability to push the beer out the keg and through the line to your tower before your beer becomes flat Remember that something has to offset the liquid volume lost during serving
Natural carbonation is just to carbonate your beer not carbonate and serve
Thank you, just wanted confirmation on that. it was what i seemed to read before starting this.