Priming sugar amounts vs. Finishing SGs

[TripHops]

Hi guys,

I have been trying to research information regarding how much priming sugar to use for bottle conditioning at different stages of final gravity. What I mean is that if you have a beer with a final gravity of 1.012 vs. another with a final gravity of 1.005, what amount of priming sugar is optimum for each to attain a consistent volume of Co2 in the bottle.

I guess the easy answer is to bottle from a keg with beer already carbonated. That may be true for some styles but when you are talking about Strong Belgians and Bavarian Wizen biers, the sediment from the bottle conditioning is key to some of their flavors.

I have read and used the standard 2/3, 3/4 cup cane sugar in 3 cups of water, boiled then chilled and added to the racked beer before bottling. However, it has been my experience that depending on how much residual fermentable sugar remains in the beer sometimes causes bottle bombs to occur.

So, does anyone know if there are some experimental charts or facts that match the finishing gravity numbers to the amount of priming sugar added to achieve consistency in the volume of C02 in bottle conditioning?

Thanks for any help you guys can give.

Trip

 

[TripHops]

Shoot, I put this in the wrong forum. It should have gone into the Bottling/Kegging forum. Sorry about that.

Trip

 

[BBL_Brewer]

By my line of thinking, it shouldn't make a difference what the FG is. Once the beer has reached terminal gravity, all that should be left is mostly unfermentables. For instance, if you brew a 1.070 grav beer vs. a 1.050 beer, the FG will definitely be different. I don't think this calls for less priming sugar in the bigger beer. Alternatively, if you mash at say 156-158 vs 150-152 you will have a difference in FG, but again no need to reduce priming since unfermentables are affecting the FG. If you have a stuck fermentation and know good and well that there are still plenty of fermentables left in the beer, then make adjustments as needed.

 

[TripHops]

Yes, BBL you and I are on the same plane on this. Different mash temp ranges will certainly change the FSG because of unfermented sugars. But I do know that given enough time, yeast will always consume all fermentable sugars in the wort. The problem is how long is to long before the yeast began cannibalizing themselves. So when do we really know when all the fermentable are consumed...or does that really matter?

I think I am probably digging to deep into this subject. It is a bit of a problem with me to be as perfect and precise as I can. That has to come from my chemistry and math background. So I still think that for a home brewer, there should be a way to figure this out without purchasing highly specialized lab equipment like a liquid chromatograph to determine the percentage of unfermented vs. fermentable sugars in the beer at the time of bottling. It is funny, I remember using HPLG (high pressure liquid chromatography) in college biochemistry labs but I never realized how handy it would be in brewing.

Thanks for your reply,
Trip

 

[cimirie]

FG wont play a role in how much priming sugar is used. Once terminal gravity has been reached, the amount of new fermentables added is the only determinant of additional fermentation.

Having said that, high gravity beers take considerably longer to carbonate, but they do so with the same amount of priming sugar.

Edit: in your last post, you asked how a homebrewer could know when all the available fermentables have been consumed... When your gravity reading doesn't change for a week, you're there.

 

[Revvy]

It doesn't matter whether a beer is finished at 1.012, or 1.020, or 1.008 or whatever when it comes to bottle carbing the beer. Fermentation is finished. You're then adding new sugar and having a completely new fermentation which is providing the gas necessary to carb.

The only thing that DOES have a bearing is how much co2 is currently in solution, and that's NOT a product of the final gravity, but the lowest temp the beer was at during the fermentation process, that has to do with the amount of co2 drawn into solution.

BUT if you're not cold crashing or anything and your beer is pretty much the same temp throughout the process (like high 60's low 70's room temp) then it's really going to be a negligible amount already in solution.

But what you're concerned about, the finishing gravity is irrelevant.

Now as to the whole "yeast caniblizing itself/autolsys" bugaboo, don't worry about it. Palmer create panic by bringing it up, but he and Jamil have basically back pedaled and said not to be concerned. It's not 30 years ago, the yeast is much more healthier than it was back then. It doesn't die, it's cell's don't burst in normal situations.

You can have 10 or even 20 year old or more bottle conditioned beer that has no signs of off flavors because of autolysis or "yeast canibalization"

You're way over thinking/stressing a really simple process, that has worked forever. Yo don't need to be a rocket scientist or biochemist to bottle carb your beer.

 

[Revvy]

The bigger issue is not to measure your sugar by volume, but by weight. Go by a cheap 20 dollar digital scale. There are plenty of priming calculators and charts listing the carb level by style and how much to add by weight to achieve the desired volumes of co2 based on temp. Palmer's nomograph is a good one.

And this is a standard chart for carbing to style.

When I'm carbing to style, I tend to err on the side of caution for most beers and aim for the middle of the range for that style.

Just remember for most situations the standard if you aren't carbing to style is 1 ounce of priming sugar per gallon of beer produces 2.5 volumes of co2 if the beer is at 70 degrees- ish..... That's why most kits comes with between 4 and 4.5 ounces of sugar. To prime between 2 and 2.5 volumes of co2....kinda average for most beers.

If you look at the second chart, you can see that for most beer styles you pretty much can't go wrong with shooting for 2-2.5 volumes of co2. Which is 4.5-5 ounces of sugar regardless.....

 

[Revvy]

If you're getting bottle bombs, are you taking grav reading to insure that fermentation has indeed finished? It doesn't matter whether your FG is high or low, just that the beer is absolutes finished fermenting- that all the fermentable sugars have been consumed by the yeast. You can safely bottle a 1.040 beer IF fermentation has ceased, and a beer with a lower grav can cause bottle bombs, if you haven't made sure fermentation is complete, if it's still dropping, or it is stuck....and the best way to do that is to take 2 grav reading over 3 days. Or do what many of us do and leave our beers in primary for a month (but it's still a good idea to take a grav reading on bottling day or close to it just to make sure.......

My 5 year aging barleywine, that has sat in a tertiary for nearly a year has an fg of 1.040....but it's og was 1.170, so it's abv is 14.5% it's a big beer....but at 1.040 it IS finished and safe to bottle that high. It's going to need fresh yeast along with the priming sugar....but the beer is ready to bottle whenever I want it to..

 

[EllisTX]

BUT if you're not cold crashing or anything and your beer is pretty much the same temp throughout the process (like high 60's low 70's room temp) then it's really going to be a negligible amount already in solution.

This is one source of confusion for me. Is it the temperature of fermentation or the lowest temp of the beer up to bottling(let's say 32 after cold crashing)? I based priming solution of a recent clone of Brown Shugga on the final fermentation temp. It had been cold crashing for 5 days. The few bottles I've cracked so far have been way overcarbed.

 

[Revvy]

This is one source of confusion for me. Is it the temperature of fermentation or the lowest temp of the beer up to bottling(let's say 32 after cold crashing)? I based priming solution of a recent clone of Brown Shugga on the final fermentation temp. It had been cold crashing for 5 days. The few bottles I've cracked so far have been way overcarbed.

It's a hotly debated and misunderstood thing...Everyone has different opinions. But I've taken it to mean THE LOWEST TEMP ANYWHERE ALONG THE PROCESS. So if you cold crash you should factor in that some c2 from fermentation didn't go out the airlock but instead went into solution.

(But I've also wondered if you warm you beer up to room temp after you cold crashed if the co2 you draw in hasn't been released?)

I don't worry because I've never bothered to cold crash, nor do I have a setup for it, but after a month in primary my beer is already uber clear.

It's another one of those things we have to "thank" Palmer for for doing a crappy job explaining himself- just like the autolysis garbage.

 

[Revvy]

Palmer just says...

Nomograph for determining more precise amounts of priming sugar. To use the nomograph, draw a line from the temperature of your beer through the Volumes of CO2 that you want, to the scale for sugar. The intersection of your line and the sugar scale gives the weight of either corn or cane sugar in ounces to be added to five gallons of beer to achieve the desired carbonation level. Here is a list of typical volumes of CO2 for various beer styles:
British ales 1.5-2.0
Porter, Stout 1.7-2.3
Belgian ales 1.9-2.4
American ales 2.2-2.7
European lagers 2.2-2.7
Belgian Lambic 2.4-2.8
American wheat 2.7-3.3
German wheat 3.3-4.5

He never specifies at what point he means the temps of the beer at.....

 

[EllisTX]

I'll be taking the lowest temp overall approach in the future. I'd much rather my beer be a bit under carbed than over anyway.

 

[jfr1111]

Beersmith's calculator says to use the temperature at bottling. So if you bottle and the beer is at 68F, plug in 68F. I don't know about other tables... It works for me.

It also depends on how permeable your fermenting vessel is. When I do open fermentations, I account for the fact that less CO2 goes into solution due to the absence of back pressure during roaring fermentation by adding a few grams more sugar. Harldy scientific, but I target specific carbonation ranges anyway and not a specific number.

 

[Revvy]

Beersmith's calculator says to use the temperature at bottling. So if you bottle and the beer is at 68F, plug in 68F. I don't know about other tables... It works for me.

Yeah that's where I first had doubts totally about the "coldest" issue. But like I said I don't cold crash or do Lagers. So my temp range has always been only with a few degrees.

And I go by BS's priming calc as well.

 

[deggenbe]

LOL Revvy, love the avatar pic!

and thanks for the charts, i have a beer thats been perfectly carbed for a few weeks now and all of a sudden, its starting to very slowly gush. a few other remaining bottles are doing the same thing.

Anything i can do with these other than drink em faster? lol
according to the chart i shoulda used 3.5 oz of corn sugar to carb. i used 5oz as if i was blindly following a rule of thumb. i'm guessing this may have caused my overcarb.

 

[Revvy]

LOL Revvy, love the avatar pic!

and thanks for the charts, i have a beer thats been perfectly carbed for a few weeks now and all of a sudden, its starting to very slowly gush. a few other remaining bottles are doing the same thing.

Anything i can do with these other than drink em faster? lol
according to the chart i shoulda used 3.5 oz of corn sugar to carb. i used 5oz as if i was blindly following a rule of thumb. i'm guessing this may have caused my overcarb.

If a beer is carbed fine for a period of time, after the usual 3 weeks, but then starts to gush, it is more than likely a late onset infection issue. In normal situation you should able to open a beer a year or 5 or 20 and have it be carbed perfectly fine....because all the sugar has been fermented out during fermentation and again during the carbonation process. So there should be no reason to gush, unless a bug has broken down the non-fermentable sugars and starts eating them and farting co2.

I'd drink them sooner, but also treat your bottling and brewing setup as infected, and try to figure out where.

 

[TripHops]

Thanks Revvy for the great information. The charts you posted will be very helpful in the future. The one thing you brought up that I hadn't thought about is the amount of Co2 already in solution after primary fermentation is complete. You certainly don't want to agitate the beer to remove it but it would seem somewhat negligible. I would think that cold conditioning would not have any affect to the volume % of Co2 already in suspension. Is that a correct assumption?

Thanks again Revvy,

Trip.