Is Palmer wrong about priming sugar?

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rocketman768

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Let's say that I have 5 gallons of fermented, un-primed beer sitting at 65F. According to the article by BYO, 4 oz (by weight) of corn sugar (of the monohydrous variety) should produce a total carbonation of 1.36+0.894=2.25 volumes.

Now, using John Palmer's nomograph, adding 4 oz (by weight) of corn sugar produces 3.4 volumes of carbonation. WTF mate?

I have a feeling BYO is right and Palmer is wrong, because up until now, I have been using Palmer's method and always thought my beers came out flatter than I wanted, and also because I can see BYO's method and formula, which works out to be...

Volumes added per 5 gal batch = 0.0132 * (grams of glucose).

Of course, please flame me if I am reading the nomograph wrong.
 
Let's say that I have 5 gallons of fermented, un-primed beer sitting at 65F. According to the article by BYO, 4 oz (by weight) of corn sugar (of the monohydrous variety) should produce a total carbonation of 1.36+0.894=2.25 volumes.

Now, using John Palmer's nomograph, adding 4 oz (by weight) of corn sugar produces 3.4 volumes of carbonation. WTF mate?

I have a feeling BYO is right and Palmer is wrong, because up until now, I have been using Palmer's method and always thought my beers came out flatter than I wanted, and also because I can see BYO's method and formula, which works out to be...

Volumes added per 5 gal batch = 0.0132 * (grams of glucose).

Of course, please flame me if I am reading the nomograph wrong.

Given your inputs I get about 2.6 volumes using Palmers graph. I think you are using it incorrectly. You have to connect the desired volumes and current temp using a straight edge. The amount of sugar needed is on the same line. You are just reading directly across from sugar to volumes.

Craig
 
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Looks like 2.5 volumes to me. Close enough for government work...
 
First, why did you connect the line to 65F? Was it because I said my un-primed beer was at 65F? Volumes are given at STP which is 0C and 1 atm, so I always assumed I should be connecting his line to 32F. "Draw a line from the temperature of your beer through the Volumes of CO2 that you want." I have interpreted that to mean the serving temperature...fck.
 
If the volumes were always at 32F, there wouldn't be any need for a temperature line.
 
First, why did you connect the line to 65F? Was it because I said my un-primed beer was at 65F? Volumes are given at STP which is 0C and 1 atm, so I always assumed I should be connecting his line to 32F. "Draw a line from the temperature of your beer through the Volumes of CO2 that you want." I have interpreted that to mean the serving temperature...fck.

Wrong. You are using the temperature of the beer currently. As colder beer has more co2 dissolved into solution, you need less priming sugar to carb it. As an example, I have a lager at 34 degrees. I want to carb it to 2.4 volumes of co2, so I can add 3 ounces (more or less, I didn't actually draw the line) to carb it up. I'll leave it at room temperature for 3 weeks, then serve it at 38 degrees. The serving temperature doesn't have a thing to do with the amount of priming sugar needed. I can serve it colder, or warmer, and it'll still have the same volume of co2.
 
Of course, please flame me if I am reading the nomograph wrong.

Please delete thread. I am stupid.

LOL! Which do you really want? :D

I'd like to keep this thread, for several reasons. One is that if this question occurred to you, then it definitely came up for other people who were afraid to ask. Two, our policy is NOT to delete threads, unless there is a pressing reason. Feeling a bit silly may be uncomfortable for you, but really isn't a reason to delete a thread.

Lastly, if we deleted every post that had a "stupid" question, I'd been down to 2,000 posts! Seriously, my first few posts on here covered such topics as "Help! The airlock didn't bubble!" and "Help! The rubber grommet fell into the wort!". At least your question was thought out and you knew what you were attempting. Most of us just sort of muddle into it blind, and ask HBT here for help! All questions are a learning experience for somebody- that's why this is a forum!
 
actually, threads like this are very useful.

I'm taking more of an interest in carb levels, and I too "read" Palmer's nonograph as serving temperature.

I learned something...:D

Ditto. While I usually keg now there are a few styles I prefer to bottle. Thanks.
 
Q never was stupid in the 1st place. This was one of the most common questions on Mr. Beer Fans as brewers ventured into batch priming.
 
Dont feel bad.. I had not referenced Palmers Nomograph for carbing before, however I am sure pretty sure i would have not used it correctly the first time.
Now I will know.
 
This is a good thread. I think carbonation and how temperatures relate are less understood than many think. First, nothing against Palmer, but why not just use this? That way you don't have to use a T-Square.

The lower the temperature of the beer at the time of bottling, the more CO2 will be in solution. This is why we account for temperature when priming beer for carbonation. The more CO2 already in solution, the less sugar we have to add.

But, IMO, there are a few factors unaccounted for in these carbonation calculators. Transfer of the beer to the bottling bucket will give off some CO2, even if transferred "quietly". But that's probably minimal, so we'll consider it negligible.

But what gets me is the CO2 content in beers that may be at a lower temperature when bottling, but may have finished fermentation at higher temps. So, which temp do you use?... the last highest temp?... or the current low temp? When lagering, surely some CO2 is produced during the lagering period, but is it as much as the carbonation calculators account for?

IOW, if you have a lager that primaried at 50°F, had a diacetyl rest at 60°F (CO2 would have been off-gassed there), then lagered at 33°F, WTF temperature do you use for your carbonation calculations? If it finishes fermenting at 60°F, it's going to have had CO2 come out of solution at that temp. It's probably not going to gain much CO2 during lagering, so should you use the 60°F for the carbonation calculation?

I guess I don't care since I force carb now, but I raised this question on here back in my bottling days with no answer. I think it would be useful to figure out.
 
The differing conditioning temperatures brings up some interesting issues. It would partially depend on whether or not you rack before lagering. This would remove the CO2 rich atmosphere above the beer. Even with a pure CO2 layer and a gallon of head space, and assuming it absorbs all of this CO2, it would only take up about 40% of the differing capacity between room temperature and 0C.

Of course you could just let it warm to room temperature before bottling.
 
Of course you could just let it warm to room temperature before bottling.

That's a good point... let the beer come to bottle conditioning temperature before bottling. But that might only be applicable if your bottle conditioning temperature is warmer than every other temperature the beer has gone through. For instance, if carbonating with saved wort, you'd want to bottle condition at primary fermentation temps, which is colder than a diacetyl rest. So, would you use the diacetyl rest temperature?

But you also raise a good point with head space CO2 in the carboy. How much of this will the beer "reabsorb" into solution when going from warmer temps to colder temps?

The other question is, how long does it take for beer to equilibriate CO2 content with temperature? Minutes? Hours? For instance if you were bottling a lager you just pulled out of the cooler at 33°F, you might be obliged to use this temp. for your carbonation calculation. But by the time the beer is going into the bottles (maybe an hour later), it might be at 50°F. So, is the CO2 content in the beer reflective of 33°F or 50°F?
 
Lucky for me my beer is nearly always at a constant temp until I put it in the fridge for consumption. So once I figured out how to read the chart (I read it wrong when I first looked at it using serving temp instead of fermention temp) it is pretty easy.

Craig
 
I'm glad someone learned from my stupidity!

I actually understood very well how temperature and gas volume relate since I took thermodynamics and understood it. I just never really payed any attention to the nomograph until you people showed me how it was supposed to be done. :)

By the way, why isn't carbonation measured in mols of CO2 per liter of beer? Seems like it would be less headache that way... Carbonation added = (grams glucose)/(180 g/mol) * (2 mols CO2 per mol glucose) / (liters of beer). That's what you're essentially measuring anyway since you are fixing the temperature and pressure to be 0C and 1 atm.
 
The other question is, how long does it take for beer to equilibriate CO2 content with temperature? Minutes? Hours? For instance if you were bottling a lager you just pulled out of the cooler at 33°F, you might be obliged to use this temp. for your carbonation calculation. But by the time the beer is going into the bottles (maybe an hour later), it might be at 50°F. So, is the CO2 content in the beer reflective of 33°F or 50°F?

Bulletin of the Chemical Society of Japan:   (1932) , 

Look at equation 4. They don't give units for the variables, but if I am calculating K correctly, then the rate of solution is indistiguishable from 0 since the value of u_0' is apparently about 1500 m/s.
 
I'm looking into priming my beers in cornys as I don't have enough room in my kegerator to force carb more than 2 kegs at a time as well as various other complications. Anybody know of a nomograph for keg priming or should I just subtract the normal weight difference between keg priming and bottle priming?
 
I am lagering two beers at 35 degrees. Going by Palmers nomograph, I should be mixing in about 2.2oz of priming sugar. Right?
 
This is a great topic. I too thought that the temperature was the serving temperature.

So, If i ferment an Ale at 68F for a three week long primary, and then crash cool the beer in my garage at 38F for two days. Immediately after the two days, i bring the beer inside, rack it, add the priming sugar and bottle it. it sits in my basement where it warms up to 62F during conditioning.

What temperature should I use on the nomograph?
 
This is mostly over my head but very interesting to me. I hope someone figures this out so I can just do what I'm told. :)
 
This is a great topic. I too thought that the temperature was the serving temperature.

So, If i ferment an Ale at 68F for a three week long primary, and then crash cool the beer in my garage at 38F for two days. Immediately after the two days, i bring the beer inside, rack it, add the priming sugar and bottle it. it sits in my basement where it warms up to 62F during conditioning.

What temperature should I use on the nomograph?

The highest temperature it was at after co2 production ceased. So 68.

Think about what is happening. At 68 co2 production happens and the liquid will have as much co2 dissolved as it can at 68. When you cool to 38 co2 solubility increases but there is no source of new co2 so all that happens is most of the existing co2 stays in solution. When you warm to 62 F you still have less than or equal to the amount of co2 that saturates beer at 68 F so again, much of it will stay in solution.
 
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