Naturally carbing a keg. Co2 volumes question.

[HopsAreGood]

I’m planning to carbonate a keg with a mixture of about 4 oz dextrose and 2 grams of CBC-1. The Lallemand calculator puts this at about 2.3 volumes at room temp (68-70 Fahrenheit)

My question is if I do this at room temp and achieve the 2.3 volumes I’m looking for, will it remain at the 2.3 volumes after I chill it down to serving temperature?

I’ve always force carbed using the classic keg carb chart when the beer is at my desired serving temp but have never done it this way.

Thanks in advance.

 

[VikeMan]

When you change the temperature, the CO2 in the beer itself will change slightly, because the equilibrium between the CO2 in the beer and the CO2 in the headspace changes. IMO, it's not worth worrying about. The total CO2 in the bottle won't change.

Also, it doesn't matter what temperature you carbonate at (as far as the overall amount of CO2 that will be produced), as long as it's warm enough that the yeast are active. The reason the calculators ask you for the temperature is so they can estimate how much residual CO2 from fermentation is still in the beer.

 

[HopsAreGood]

When you change the temperature, the CO2 in the beer itself will change slightly, because the equilibrium between the CO2 in the beer and the CO2 in the headspace changes. IMO, it's not worth worrying about. The total CO2 in the bottle won't change.

Also, it doesn't matter what temperature you carbonate at (as far as the overall amount of CO2 that will be produced), as long as it's warm enough that the yeast are active. The reason the calculators ask you for the temperature is so they can estimate how much residual CO2 from fermentation is still in the beer.

Thanks for this. The lowest suggested ferm temp for CBC-1 is 59. It would be great if it worked at serving temps but I doubt it would.

I’m thinking of typical fermentation in the fermenter, then transferring into my dry hop keg where I’ll dry hop cooler than room temp. Then transferring into my serving keg that ill allow to warm up to room temp, then inject the sugar/CBC-1 mixture through the keg post. Let carbonate at room temp for a few days, then chill to serving temp. Do you see any issues with this plan?

 

[VikeMan]

I’m thinking of typical fermentation in the fermenter, then transferring into my dry hop keg where I’ll dry hop cooler than room temp. Then transferring into my serving keg that ill allow to warm up to room temp, then inject the sugar/CBC-1 mixture through the keg post. Let carbonate at room temp for a few days, then chill to serving temp. Do you see any issues with this plan?

I see no issues with the plan.

 

[VikeMan]

Adding: I don't know what you mean by "a few days," but I'd recommend 2-3 weeks for carbonation, unless you know for sure it's done earlier. My experience with natural carbonation is that many people think their beers (usually bottles) have finished carbonating because they pop and fizz. Of course they do... that's what CO2 does, even when there's less of it.

If you have a pressure gauge that you can attach to the keg's gas post, you'll be able to see when it has reached full carbonation.

 

[HopsAreGood]

Adding: I don't know what you mean by "a few days," but I'd recommend 2-3 weeks for carbonation, unless you know for sure it's done earlier. My experience with natural carbonation is that many people think their beers (usually bottles) have finished carbonating because they pop and fizz. Of course they do... that's what CO2 does, even when there's less of it.

If you have a pressure gauge that you can attach to the keg's gas post, you'll be able to see when it has reached full carbonation.

I’ve seen many anecdotal reports of CBC-1/dextrose being pretty much done in 2-3 days. I’ve never tried myself so I can’t say for sure.

If you read this and the next few posts after it.....

https://www.homebrewtalk.com/thread...identify-and-characterize.623221/post-8963417
I’ve also read other similar experiences.

 

[VikeMan]

I’ve seen many anecdotal reports of CBC-1/dextrose being pretty much done in 2-3 days. I’ve never tried myself so I can’t say for sure.

CBC-1 may well be faster than average. I don't really know. I've read the same claims, but never with data. Personally, I wouldn't rely on anecdotes for something like this, unless these folks had actually measured the pressure and confirmed it had reached the appropriate level.

This could actually make for a great split batch experiment, with gauge equipped kegs.

 

[HopsAreGood]

I’ll report back after I try this in the near future.

 

[VikeMan]

"Then I let them carbonate at room temperature (usually takes 24-48 hours)"

Right. But how does he/she know it's finished?

 

[HopsAreGood]

"Then I let them carbonate at room temperature (usually takes 24-48 hours)"

Right. But how does he/she know it's finished?

I’m not saying they do know for sure. But they seem to have done this a number of times and were satisfied with the level of carbonation after the 24-48 hours.

“I have checked it at 24-48 hours and it’s usually fully carbonated at that point.”

Maybe @MrPowers could chime in at some point.

 

[marc1]

You could check your gravity to see if the priming sugar is all consumed

 

[MrPowers]

When using CBC-1, you can either pull a sample to check the gravity (be very careful using picnic taps, because the PSI at room temp may crack the valve), or very gently test the PRV valve to see how much pressure has built up in the keg.

Or just pull a glass and taste.

 

[VikeMan]

When using CBC-1, you can either pull a sample to check the gravity

This would work (but don't forget to degas the sample).

or very gently test the PRV valve to see how much pressure has built up in the keg.

Or just pull a glass and taste.

These would tell you if there is carbonation, but not whether or not it's fully carbonated, i.e. all priming sugar fermented.

 

[HopsAreGood]

When using CBC-1, you can either pull a sample to check the gravity (be very careful using picnic taps, because the PSI at room temp may crack the valve), or very gently test the PRV valve to see how much pressure has built up in the keg.

Or just pull a glass and taste.

In your experience, when carbonating a keg with CBC-1 and dextrose, did you find that it was nearly or completely carbed in a few days?

 

[MrPowers]

This would work (but don't forget to degas the sample).



These would tell you if there is carbonation, but not whether or not it's fully carbonated, i.e. all priming sugar fermented.

That's true, but you can tell based on headspace pressure/head on the pour ABOUT how carbonated it is. After trying it a few times, you will get a feel for how far along it is.

In your experience, when carbonating a keg with CBC-1 and dextrose, did you find that it was nearly or completely carbed in a few days?

I would usually be able to put it in the fridge on day 3-4.

 

[HopsAreGood]

So I transferred a fully fermented beer into a liquid purged keg yesterday. Prior to transferring the beer, I added a mixture of 4 oz dextrose dissolved in 6 oz water, and 1.8 grams of CBC-1. I then injected that mixture through the QD on the gas post of the keg. I then transferred the beer on top of that, and sealed the keg with 30 psi.

The temp of the beer was 65 and I let it sit at room temp for the past 24 hours. I just pulled a sample glass out of curiosity to see if it was “working” and it is looking great. It appears to have a very nice level of carbonation. There is definitely a nice head to the beer, but it does fall fairly quickly. Also, when I tilt the glass to one direction, then tilt it quickly to the other direction, the amount of bubbles that rise to the surface look exactly the same as my other beers that are “fully” carbed.

So I can’t really say that it’s definitely completely carbonated, but it sure looks like it is. I’m going to give it another 24 hours, pull another sample and then decide if I’m going to stick it in the fridge.