Does force carbing = lower ABV than using priming sugar?

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If you are adding sugar to create more fermentation in order to produce co2 for bottling, then aren't you also creating more alcohol? So if you force carb in a keg rather than prime, is it a lower ABV? Or is the priming sugar not a significant enough of an amount to make a difference?
 
yes, technically any yeast fermentation of sugar will result in alcohol production, so bottle conditioned beers have additional alcohol. But practically, the amount added is probably less than 0.1%

EDIT: this got me thinking...if I use 4oz of sucrose to bottle 5 gallons of beer, this will add approximately 2 gravity points [sucrose = 46 points per pound per gallon]. Assuming the yeast completely ferment the added sugar, those 2 gravity points would result in an increase of approximately 0.25% alcohol. So you could assume your bottled beer has a quarter of a percent more alcohol than your force-carbed beer.
 
if I use 4oz of sucrose to bottle 5 gallons of beer, this will add approximately 2 gravity points [sucrose = 46 points per pound per gallon]. Assuming the yeast completely ferment the added sugar, those 2 gravity points would result in an increase of approximately 0.25% alcohol.


so the practical answer is not really. :)
 
I would say 0.25% is a decent amount, especially since most people don't contemplate it in their ABV.
 
Not to hijack your thread, but along these lines, does force carbing result in a longer or shorter (or doesn't it make a difference) conditioning time?
 
:off: When I bottle, I expect 3 weeks for carbonation. When I keg, I expect 3 weeks for carbonation - now it doesn't really take that long - at one week, it's carbonated (set it and forget it). There are those that set the pressure high and shake hell out of it - and get there in 30 minutes...
but If I set it and forget it, the bubbles, the blending, the aging, it's all very good at the 3-week point.

So, as long as you have something else to drink....:D
 
Not to hijack your thread, but along these lines, does force carbing result in a longer or shorter (or doesn't it make a difference) conditioning time?

It doesn't change the time needed for conditioning. Green beer is green beer. With kegging, though, you could have carbonated green beer quickly.

I guess that in one respect, kegged beer could take even longer than bottle conditioned beer to be ready. Usually, I keg my beer and stick it in the kegerator. It takes a beer much longer to condition at cold temperatures, and beer ages faster at room temperature. So, in that respect, if you keg green beer and put it in the kegerator it can be green a long time.
 
It doesn't change the time needed for conditioning. Green beer is green beer. With kegging, though, you could have carbonated green beer quickly.

I guess that in one respect, kegged beer could take even longer than bottle conditioned beer to be ready. Usually, I keg my beer and stick it in the kegerator. It takes a beer much longer to condition at cold temperatures, and beer ages faster at room temperature. So, in that respect, if you keg green beer and put it in the kegerator it can be green a long time.

This is why I have resorted to what Biermuncher has said he does before. I will keg my beer, hit it with enough CO2 to seal the keg, sit it in the closet until I am ready to carb up and serve. That way, the beer stays fresher with the CO2 onto, and it conditions faster at room temperatures.
 
This is why I have resorted to what Biermuncher has said he does before. I will keg my beer, hit it with enough CO2 to seal the keg, sit it in the closet until I am ready to carb up and serve. That way, the beer stays fresher with the CO2 onto, and it conditions faster at room temperatures.

Yeah, I tried this and it was torture. If I put it in the kegerator right away, then I can drink it right away. It might be green, but it's still beer!
 
Interesting thread.

I'm going to keg in a week.

(thinking to myself)

What to do :confused:, what to do :). I do have about a case of bottled beer. So I could wait a few weeks to drink from the keg. So do I add a little CO2 and let it sit at room temp for a few weeks and let it mature or force carb and put it in the fridge and drink it a little green?

I think I'm going to let it condition in the keg at room tempurature.

(done thinking)

Sorry it's Friday. I get a little weird when it's beer drinking time.

Question: Will I need to add more CO2 to the keg (at room temperature) to keep the pressure up. I assume that the CO2 will be absorbed into the beer.
 
Question: Will I need to add more CO2 to the keg (at room temperature) to keep the presure up. I assume that the CO2 will be absorbed into the beer.

Yes. Plus, when you put it in the fridge/kegerator, the colder temps will make the beer denser, thus lowering the volume of the beer. This will increase the volume of the headspace and lower the pressure.

If you don't keep the gas on the keg all the time, then you will have to top it off every day until the beer is saturated. Once it reaches equilibrium, you can take the gas off until you start to pour.
 
Yes. Plus, when you put it in the fridge/kegerator, the colder temps will make the beer denser, thus lowering the volume of the beer. This will increase the volume of the headspace and lower the pressure.

Yes, but not by much. A 12 oz bottle that contains 11.50 oz will shrink to 11.48 oz when you take it from 70F to 38F. That's only a 4% change in headspace.
 
Since this is my only keg that will be filled, I'll just keep the CO2 on it at room temp for a week or two and put it in the fridge after that.

Does 10 PSI sound about right?
 
:off: When I bottle, I expect 3 weeks for carbonation. When I keg, I expect 3 weeks for carbonation - now it doesn't really take that long - at one week, it's carbonated (set it and forget it). There are those that set the pressure high and shake hell out of it - and get there in 30 minutes...
but If I set it and forget it, the bubbles, the blending, the aging, it's all very good at the 3-week point.

So, as long as you have something else to drink....:D

When I keg, most of the time I'm drinking it that night.
 
Since this is my only keg that will be filled, I'll just keep the CO2 on it at room temp for a week or two and put it in the fridge after that.

Does 10 PSI sound about right?

10 PSI at room temp will probably be a little under carbonated when you refrigerate it.
 
10 PSI at room temp will probably be a little under carbonated when you refrigerate it.

A LOT under carbonated !! You will have to chill it to serving temp and leave 10 psi on it for at least a week to get proper carbonation. Or chill it and force carb by the chart.
 
. . . . .
Question: Will I need to add more CO2 to the keg (at room temperature) to keep the presure up. I assume that the CO2 will be absorbed into the beer.

Or......you could prime it in the keg for natural carbing. I usually add 2/3 cup dextrose to the keg, turn it upside down to make certain there are no leaks, fix leaks, then in a couple days pull the relief a little to allow the oxygen to purge, then wait the appropriate time for conditioning at room temp, then fridge for a couple days to a week.:rockin:
 
Two questions:

What would anyone recommend for CO2 PSI if I were to leave it pressurized at room temp., and then what PSI once I refrigerated it?

Also, if I do prime it instead, doesn't that create more sediment at the bottom of the keg?

OK, I think that's 3 questions.
 
Two questions:

What would anyone recommend for CO2 PSI if I were to leave it pressurized at room temp., and then what PSI once I refrigerated it?

Also, if I do prime it instead, doesn't that create more sediment at the bottom of the keg?

OK, I think that's 3 questions.

I wouldn't try to carb it at room temp (it would take nearly 30 psi) so purging a few times and leaving it at 10 psi will be enough to let it condition. Same goes for priming it except that it will slowly build pressure. There won't be an appreciable mount of extra sediment. Just pour the first draw in the sink and then you are good to go.
 
I wouldn't try to carb it at room temp (it would take nearly 30 psi) so purging a few times and leaving it at 10 psi will be enough to let it condition. Same goes for priming it except that it will slowly build pressure. There won't be an appreciable mount of extra sediment. Just pour the first draw in the sink and then you are good to go.

So your saying to leave it at 10 PSI, but do it while it's in the fridge? Or use priming sugar and leave it a room temp for a while. Is that correct?
 
Yep, it will take about a week to reach proper carb levels with 10 psi CO2 applied in the fridge, two weeks to naturally carb at room temperature with priming sugar, or about an hour to force carb at serving temp with plenty of shaking. Your results may vary.
 
Priming with 10 grams of glucose per liter will raise the ABV by .65%
5 US gallons = 19 liters so 190 grams of Glucose
Using a syrup which has 90 grams of Glucose per 100 ml water = roughly corn syrup 211 ml
you would add 7.1 US fluid ounces for priming and this will raise the ABV by .65%
Forced carbonation will not raise the ABV
 
This thread is 4+ years old, so the people who posted probably no longer care. But since it was recently commented on, I will provide this:

Priming with only sugar will increase ABV a little. However, priming with a sugar SOLUTION (as is more common) may or may not increase ABV. If the OG of the priming sugar solution is higher than the OG of the beer, ABV will be very slightly increased. Conversely, if the OG is lower than the OG of the beer, the added sugar solution will actually decrease the ABV because of dilution.
 
Sorry you are wrong. Priming with 5 grams of 50% Glucose solution ( 500grams per Litre ) in a 500ml bottle of 5% ABV beer will raise the ABV over 10% to 5.54%ABV.
Follow this example. 490ml of 5% ABV beer is put in a bottle which now has a total absolute alcohol volume of 24.5ml
Priming with 10ml of aforementioned glucose solution. This adds 5 grams of glucose which will ferment into 2.56 grams of Ethanol which has a volume of 3.24ml. Total alcohol in the 500ml bottle is now 24.5+3.24 = 27.74ml / 500 = 5.54%. The ABV of the bottle is now 5.54%
Adding 5 grams of Glucose to a bottle and then adding 500ml of 5% beer will change the ABV to 5.6%
 
Sorry you are wrong. Priming with 5 grams of 50% Glucose solution ( 500grams per Litre ) in a 500ml bottle of 5% ABV beer will raise the ABV over 10% to 5.54%ABV.
Follow this example. 490ml of 5% ABV beer is put in a bottle which now has a total absolute alcohol volume of 24.5ml
Priming with 10ml of aforementioned glucose solution. This adds 5 grams of glucose which will ferment into 2.56 grams of Ethanol which has a volume of 3.24ml. Total alcohol in the 500ml bottle is now 24.5+3.24 = 27.74ml / 500 = 5.54%. The ABV of the bottle is now 5.54%
Adding 5 grams of Glucose to a bottle and then adding 500ml of 5% beer will change the ABV to 5.6%


No apology necessary. We are in agreement. Your example has a relatively low ABV beer (for homebrew...they certainly can be lower, but are often much higher). Rerun numbers with a 10% ABV beer and prime with a 20% glucose solution. All I'm saying is that there is no standard increase in ABV and that it could decrease. This is more of an issue when adding fruit when there is an assumption that a lot of sugar is added, when in reality a little sugar is added and a lot of volume.

Now that I think about it, I never actually ran the numbers to see how diluted the priming solution needs to be to reduce ABV. But it IS based on the ABV of the beer and the concentration of sugar in the priming solution. While I may have over generalized and included unrealistic examples in my thinking, I am still convinced that adding a solution with a lower OG than the beer's OG WILL reduce ABV.

Then again, I've been wrong before. Thanks for the info.
 
So, if my math's right a priming solution of 2 cups of water and 4 ounces of corn sugar has a gravity of 1.088. That has the potential of maybe 10% ABV.

If your 5 gallons is at 5% ABV:

(5gal x 5%abv) + (.125gal x 10%abv) / 5.125gal (total volume) = 5.12%abv (after priming)

A 5% beer goes to 5.12%.
If the beer is already at 10% it doesn't change?
:confused:
 
Precisely.

And if your yeast only attenuated 75% (apparent attenuation), your 1.088 OG priming solution will ferment to 1.022, which is roughly 8.8% ABV (check my math, I did that in my head). So if you add it to a 5% ABV beer, it would increase the ABV. Exactly as you showed via the rule of mixtures. However, if you added it to a 10% ABV beer, it would reduce the ABV.
 
Well in the interests of science & beer comradeship lets run your example 10% ABV homebrew and 20% priming solution
490 ml of 10% hombrew into our 500ml bottle adds 49ml of Ethanol. Adding 10 ml of 20% Glucose adds 2 grams of glucose which will ferment into 1.02 grams of Ethanol which is 1.29ml. Our bottle now has 500ml with 49+1.29 = 50.29ml = 10.06%ABV - a small increase indeed but 10ml of 20% Glucose will leave a pretty flat beer ( although possibly not in English pubs) and 10%ABV homebrew is near the top end.
At 7% ABV Homebrew and 10 ml of 50% Glucose solution the final ABV will be 7.51%, still significant I think. Especially when it comes to paying excise. Adding 5 grams of glucose powder to 500ml of 7%ABV will raise it to 7.65%ABV. Which is a having a sleep under a tree beer.
Regards from South Australia
 
and adding either 20% or 50% priming solution will never lower the ABV. It will always increase it.Adding 300 ml of 20% priming solution to 200 ml of 7% ABV beer will give a final ABV of 10.6%.
Even starting with a 10% ABV beer and adding 10ml of 20% priming solution will give a final ABV of 10.06
Starting with 200ml of 10% ABV beer and adding 300 ml of 20% priming solution will give a 11.8% beer
Remember a 100 ml of 20% solution of glucose will become ( with perfect yeast ) 100ml of 12.96%ABV therefore you will only begin diluting your homebrew with priming if your homebrew starts with an ABV greater than 12.96%
 
From How to Brew:
Here's how to make and add priming solutions:
1. Boil 3/4 cup of corn sugar (4 oz by weight), or 2/3 cup of white sugar, or 1 and 1/4 cup dry malt extract in 2 cups of water and let it cool.......

This would give you a 1.088 solution and giving you the benefit of the doubt, at 90% attenuation, 10% abv. You can make your priming solution to a higher gravity and make the numbers say what ever you'd like, but that is not the standard most homebrewers go by.
 
Well in the interests of science & beer comradeship lets run your example...

And that is exactly how far I read before assuming you had me :)

So I'll respond with the following:

All I heard is that "priming with a solution with a lower OG than your beer's OG will result in a reduced ABV."

But seriously, thanks for showing the absurdity of my position. I still think we were both right from the start, although your position is much more practical.
 
No I don't make the numbers say what ever I like. What I have shown is science.
 
No I don't make the numbers say what ever I like. What I have shown is science.


You lost me...

I never implied that is what you did. I never suggested you were twisting the figures. I never suggested you did anything wrong at all.
 
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