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Priming calculators wrong?

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I may as well go back to the "standard" amount of priming sugar. I was never disappointed with the carbonation of my beer until I started using the calculator tools.
 
Im going to find a "perfect" weight of corn sugar through experimentation and then make that my go to for priming.

As to how much CO2 remains in solution, I THINK it would depend on time and temp AFTER fermentation stops as part of the equation. Open a beer and let it sit out, carbonation drops over time. With nothing to maintain pressure in a fermentor, dissolved gasses would want to reach an equilibrium. I think its a moving target with several variables to consider.

Time after fermentation,
density of the solution
surface area exposed to atmosphere
temp of solution
how saturated with co2 was the solution?
How much co2 could the solution hold at atmospheric pressure?

So yes, I guess it is a much more complicated calculation than "dark beers get X oz of sugar, Light beers get Y oz of sugar.

Great discussion !
 
One must remember that there is always a full equilibrium at the molecular level along the surface of the beer solution whereby gas is actively leaving the solution and going into the headspace above it, and at the same time, and at the same rate actively going out of the headspace and dissolving back into solution. The difference between a glass sitting on the countertop and what is happening in the airlock confined fermenter, is that for the glass the headspace above it is air, and for the confined fermenter (assuming that you haven't futzed with it) the headspace is pure CO2. As a consequence, the glass goes flat as air eventually replaces CO2 in solution, and the fermenter doesn't.

In general, due to the above if there are no bubbles exiting the airlock, there is no 'net' dissolved CO2 departing from the solution. It could remain relatively unchanged for months.
 
This thread has me thinking of giving DME a shot at priming the ale that's presently in my fermenter. I've never tried it before. How does 1 level cup (~165 grams) of Muntons Amber DME or Breiss Golden Light DME sound for a nominally 5 gallon yielding batch that should come in at about 15 SRM?

It will either be that, or 115 grams of granulated white table sugar.
 
I'm noting that most everyone on this thread is using corn sugar for priming. Waste of money so far as I'm concerned. Use the 45¢/lb. cane sugar from the supermarket, and buy a good scale for weighing the amount instead of unreliable measuring by volume.
 
Confectioners sugar is also good. (Powdered sugar). I get a lot of foam in my bottles when filling and using the black Fortune bottles will be hard to fill properly with so much foam in the bottle. Lots of waiting. How does cane sugar compare to Dextrose in that category?

Also, I prime in the bottles. I know it is a PITA to do 50 12 oz bottles, or half that in bigger bottles, but my batches always seem to be higher or lower in volume but the bottle size stays the same. I spoon feed them. But I may try powdered sugar next time. I know I tried it several years ago and somehow forgot about using it. Thanks for the reminder. (Oh, C&H is cane and generics are usually beet sugar, which is not as good as cane. C&H confectioners sugar is also cane.)

Update: Did some searching and found a few comments about confectioner's sugar. It all contains either corn starch or silicates or both, used as anti-caking ingredients. Neither are especially good for the beer. In my experience I did not notice any difference in the priming nor the taste or quality. But, thinking back, my beer had what seemed an extra bit of sediment in the bottom of the bottle.

Good enough for me. I don't like the sediment so, I will probably not use it. No sense adding more sediment to the brew.
 
This thread has me thinking of giving DME a shot at priming the ale that's presently in my fermenter. I've never tried it before. How does 1 level cup (~165 grams) of Muntons Amber DME or Breiss Golden Light DME sound for a nominally 5 gallon yielding batch that should come in at about 15 SRM?

It will either be that, or 115 grams of granulated white table sugar.

That seems low to me. You'd have to look up the specifics on the fermentability of the specific DME, but I'd think about 8 ounces by weight would be about right. Is that about 225 grams(?)- metric impaired here but trying to convert in my head.
 
Confectioners sugar is also good. (Powdered sugar). I get a lot of foam in my bottles when filling and using the black Fortune bottles will be hard to fill properly with so much foam in the bottle. Lots of waiting. How does cane sugar compare to Dextrose in that category?

Also, I prime in the bottles. I know it is a PITA to do 50 12 oz bottles, or half that in bigger bottles, but my batches always seem to be higher or lower in volume but the bottle size stays the same. I spoon feed them. But I may try powdered sugar next time. I know I tried it several years ago and somehow forgot about using it. Thanks for the reminder. (Oh, C&H is cane and generics are usually beet sugar, which is not as good as cane. C&H confectioners sugar is also cane.)

Powdered sugar has corn starch and things in it, doesn't it? How do you deal with that? Or how do you decide how much to use?
 
Powdered sugar has corn starch and things in it, doesn't it? How do you deal with that? Or how do you decide how much to use?

I never noticed any problems. I will get more and report back if I do use it. Thanks for the heads up. But C%H is pure cane sugar from Hawaii, so, there may not be anything in there but sugar. I will look for the Nutrition disclosure online. Good point.

Yep, sugar and corn starch. I have been told at one point though that "confectioners sugar works well, and C&H just came to my head. I will see if there anything w/o corn starch.

*(See post #37)
 
I don't understand what you are saying in this post. You're talking about a closed fermenter, like a keg? If so, I agree that there is no gas entering or leaving if there is no leak. If you're taking about a carboy, with a bung and airlock, then it's not so. Oxygen will diffuse through the water in the airlock, the leaks around the seal, through the plastic seams of the airlock, etc, and c02 will also exit. The laws of physics come into play.

But even so, that really isn't the topic of residual c02, I don't think, unless like above, we're talking about holding the beer in a totally impermeable vessel like a keg.
 
There is a priming monograph plot in John Palmers "how to brew" which I always used. It will generally be less than what is given to you in a kit. I rarely found 5 ounces necessary for a five gallon batch.

I found the same plot here. https://2.bp.blogspot.com/-9w5i9XLua6c/VzGgALBP1mI/AAAAAAAAA04/YtYr9VAqD7UFK1yoM0yaZD6VFUfvlLPoACLcB/s1600/nomograph.png
 
One of the biggest potential mistakes people can make is in confusing volume ounces with weight ounces, or visa-versa.

I just gave a talk to my club on bottle conditioning this week and you guys are covering it nicely. This "volume" vs "weight" difference was one of the biggest 'aha' moments of my brewing so far. For me it flowed from a confusion of ounces vs ounces and so is generally not an issue outside the US.

The other issues

  • what does beer temperature mean in calculators (warmest temp after fermentation)

  • What type sugar are you using
  • What is the actual bottling volume
  • The amount of sugar shipped with a beer kit is probably too much
 
I don't understand what you are saying in this post. You're talking about a closed fermenter, like a keg? If so, I agree that there is no gas entering or leaving if there is no leak. If you're taking about a carboy, with a bung and airlock, then it's not so. Oxygen will diffuse through the water in the airlock, the leaks around the seal, through the plastic seams of the airlock, etc, and c02 will also exit. The laws of physics come into play.

But even so, that really isn't the topic of residual c02, I don't think, unless like above, we're talking about holding the beer in a totally impermeable vessel like a keg.

You are correct about gas diffusing thru the various seals, but the important question is whether or not there is enough diffusion over the time frame of interest (usually a few days), that the CO2 partial pressure in the headspace will change (decrease) by a significant amount? I would define significant (arbitrarily) as 5%. Ideally, the answer would be that CO2 partial pressure changes by less than 5% over a week's time.

I believe that the highest level of diffusion will be thru the water in the airlock vs. thru the plastic components, unless you are using a leaky bucket fermenter, in which case the leaky lid seal should dominate. It should be possible to estimate the rate at which O2 diffuses into the headspace, and CO2 diffuses diffuses out, thru the water in the airlock. This would give us an estimate of how fast the CO2 partial pressure in the headspace decreases. I'm not sure I'm up to the task of doing this at the moment, but if I ponder it for a while, I might come up with a way to approach the problem.

Brew on :mug:
 
After many years of trial and error, unless I am making a lighter style of ale, I always use 3/4 oz of table sugar per gallon and I need to wait at least 3 weeks for carbonation.
 
Well, I remember researching something about the production of champagne where the calculation of the sparkling pressure was 4g of sugar = 1 bar of pressure, so a bottle of sparkling wine has 6-7bar then 20g of sugar. I have adopted this as standard measure without any problem. For example Saison = 11g / L = 2.75bar
 
What? No Kraeusening (using Gyle a la Papazian) mentioned?

Uh, just kidding doesn't make matters clearer. I have used it a few times back when I bottled. I don't bottle any more, save the occasion when I want to set aside a bottle or two, and I scramble to Google how much to put in each 22 oz. bottle because I do it so rarely.

Meh. I'm just noise.
 
For metric I would start with 120 grams of granulated white table sugar for a 20 liter yielding batch.

6 grams of granulated white table sugar per liter of beer.
 
I always prime with DME unless I'm doing an English ale. I prime at room temperature for about 10 to 14 days then condition at about 38 degrees for a week with a hefe and longer for lagers. The cold temp sets the co2. The amounts are different than sugars and BeerSmith has a great calculator. Make sure you have reached final gravity.
 
I always prime with DME unless I'm doing an English ale. I prime at room temperature for about 10 to 14 days then condition at about 38 degrees for a week with a hefe and longer for lagers. The cold temp sets the co2. The amounts are different than sugars and BeerSmith has a great calculator. Make sure you have reached final gravity.

How much DME do you typically add, and how much do you typically bottle?
 
I've bottled carbed about 40 batches with the Northern Brewer calculator. I preferred it because of the variety of sugars it includes and the fact that it accounted for beer temp (i.e., natural carbonation) but it definitely tended to undercarb rather than overcarb. The only time I ever overcarbed was due to contamination.
 
The last two batches I made were overcarbonated using online priming calculators.

A common way to over carb is to bottle before fermentation is actually complete. The proper way to tell if fermentation is complete is to take SG readings two days apart. If the SG of the second reading is the same as the first, then fermentation is done. If the second reading is even a little bit lower, then you are still fermenting. Keep checking SG every second day until you are done. Looking for lack of airlock bubbles is not a reliable way to determine if fermentation is done.

How did you determine when it was time to bottle? If you used the measured SG method correctly, then it may be an issue with the calculator that you used. It that case, it would be useful to know which calculator that was. If you didn't use the SG method, then it's not fair to implicate the calculator in the over carb, so please don't point the finger at one.

Brew on :mug:
 
Keep in mind that you need to carbonate both the beer and the headspace of any packaging container. So your beer volume and temperature matter, but so does your fill level in bottles/kegs/etc. I made a spreadsheet that takes those variables into account, which lives here:

https://sites.google.com/site/republicbrewpub/

The file name is Carbonation_Gallons. The Recipe_Gallons file uses the same calculations and incorporates natural carbonation into recipe formulation (e.g. it'll adjust the expected ABV and target volumes/gravities based on method of carbonation).
 
Keep in mind that you need to carbonate both the beer and the headspace of any packaging container. So your beer volume and temperature matter, but so does your fill level in bottles/kegs/etc. I made a spreadsheet that takes those variables into account, which lives here:

https://sites.google.com/site/republicbrewpub/

The file name is Carbonation_Gallons. The Recipe_Gallons file uses the same calculations and incorporates natural carbonation into recipe formulation (e.g. it'll adjust the expected ABV and target volumes/gravities based on method of carbonation).

This is very true, and something usually ignored. Since bottles (other than the last one filled from a batch) are usually filled almost completely, ignoring it doesn't have a detrimental effect. A 2.5 or 3 gal batch in a 5 gal keg definitely is affected. The interesting part comes about since many/most brewers who naturally carbonate kegs initially pressurize the headspace in order to make sure they get a good seat/seal on the lid gasket. A common number I have seen for this is 30 psi, which just happens to be close to the equilibrium pressure for 2.6 volumes at room temperature (70°F.) In this case the headspace will already contain close the final volume of CO2 that it needs. However, if the brewer only seats with 10 psi, then the headspace only starts out with about half of the CO2 that it ultimately requires. (Physics quiz: why isn't it only 1/3 [10psi / 30 psi] the required amount of CO2?) Does the spreadsheet account for the starting pressure in the headspace?

Brew on :mug:
 
The spreadsheet lets you choose whether or not vessels are purged with CO2 before filling. If you choose the purged option, it assumes the headspace is 100% CO2 at the equilibrium pressure of the beer going into the vessel - which would need to be the case for successful counter-pressure filling of carbonated beer, unless the pressure was relieved afterward for some weird reason. Adding an option to the spreadsheet for pressurizing the headspace to a given pressure wouldn't be difficult, and I may do it when I have some extra spare time. In the meantime, you could estimate the impact of the pressurized headspace on the CO2 pressure of the entire batch and enter that value as the "Initial Beer Pressure" variable. The spreadsheet does its background calculations in absolute pressure, so hopefully it'll pass the physics quiz!
 
I updated the spreadsheets to let the user specify the headspace pressure, since the equilibrium pressure assumption would only be a ballpark estimate for keg filling under counter pressure and not applicable at all for bottle filling.
 
I use a spreadsheet that allows for the final temp of the fermenting beer, also what kind of priming sugar and a table (from Tasty Brew) on desired carbonation levels for beer style. But all you really need to do is use the formula (CL * S * L = Priming sugar needed)
CL = Carbonation level desired (Vols) - existing carb level in beer
S = grams of sugar required to raise 1 litre by 1 volume
L = Litres of beer

S can vary with diff sugars Dextrose 4.02g (Sucrose 3.82g) (DME 6.8g)
Existing carb level by temp 10c-1.2 Vols, 16c-0.98vols, 20c-0.73vols
 
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