Same issue. Nearly ruined an Oktoberfest.
Priming calculators wrong?
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Same issue. Nearly ruined an Oktoberfest.
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.
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
I found the same plot here. https://2.bp.blogspot.com/-9w5i9XLua6c/VzGgALBP1mI/AAAAAAAAA04/YtYr9VAqD7UFK1yoM0yaZD6VFUfvlLPoACLcB/s1600/nomograph.png
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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
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
MindenMan
Well-Known Member
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.
VonSchmitt
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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.
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.
Silver_Is_Money
Larry Sayre, Developer of 'Mash Made Easy'
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.
6 grams of granulated white table sugar per liter of beer.
troglodytes
Well-Known Member
Actually you joke, but my best beers came from krausening. Also... my only bottle bombs came from krausening.
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.
Silver_Is_Money
Larry Sayre, Developer of 'Mash Made Easy'
How much DME do you typically add, and how much do you typically bottle?
BridgewaterBrewer
Well-Known Member
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.
DarthStout
New Member
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
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).
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
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
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
I don't see this mentioned often. But conceptually it seems difficult for me to believe you can use some universal calculator. Wouldn't the structure of the beer, and the type of yeast used be a big factor? Don't yeasts all work at different rates and different potentials? Also what kind of bottles are you using and how full are they? Etc... Maybe it's simpler than I think but a "calculator" is a bit of a misnomer ; not a precision tool but an estimator. That being said I've used the N. Brewer tool, I think best thing is to use it or some other calculator a couple times, and adjust accordingly to taste.
Not really any dependency on beer type or yeast, at least if you prime with simple sugars (corn sugar [dextrose monohydrate] or table sugar [sucrose].) All yeasts will completely consume these simple sugars, and turn them into alcohol and CO2. The beer type and yeast will affect how long it takes to completely carbonate, but priming calculators aren't intended to make any prediction of time required.
The most important factor for achieving consistent carbonation levels is to make sure your beer is completely fermented prior to bottling. If you have a different amount of residual fermentables batch to batch, your carb levels will be all over the map. Use the "stable FG for three days" criterion to determine when fermentation is complete.
Bottle type will only affect the outcome if you use a bottle style that gives you a significantly different headspace to beer volume ratio (as noted by jwalts.) But if you use a bottling wand to fill to the rim, then the headspace volume will consistently be the displaced volume of the wand in the bottle. For "normal" bottle shapes, the displaced volume will not vary much from style to style. Typical headspace volume is about 6% of the beer volume. I doubt variations from 4% to 8% would change carbonation level enough to be detectable in blind testing. If you are really interested, I can calculate the difference in CO2 volumes for a range of reasonable headspace ratios.
Your best advice is in your last sentence: i.e. consistently use the same calculator, and learn the "fudge factor" to apply to get results that you like. Using multiple calculators at different times will make getting consistent results more difficult.
Brew on
Orerockon
Active Member
IMO They are conservative, I guess they don't want people blaming them for bombs. I saw recommended oz. all over the map and used 1/3 to 1/2 c. for a few batches of cider that were decidedly wimpy. Then I got ticked off and upped it to 1 c. which was perfect. Now that's what I use for every batch of cider and several variants of mead with several different yeast strains. I've had about 5 champagne bottles out of probably 1000, no bombs. I really don't think it matters what recipe as much as how much sugar your priming yeast consumes. I always go with the same yeast I used to ferment.
Silver_Is_Money
Larry Sayre, Developer of 'Mash Made Easy'
I just did a quick (and by no means fully extensive) comparison of the Northern Brewer priming calculator and the Brewer's Friend priming calculator, and from my brief observation it appears that Brewer's Friend calls for roughly 9% higher priming sugar quantities than does Northern Brewer. If Northern Brewer is an example of conservative, then by that measure Brewer's Friend does not appear to be conservative.
I assume you specified the same sugar in both cases, yes? Did you specify dextrose (corn sugar) or sucrose (cane/beet sugar)? Most dextrose is actually dextrose monohydrate, so it requires ~10% more dextrose monohydtrate than pure dextrose to carbonate to the same level. Might Northern's calculator be calculating based on pure dextrose?
The more probable cause for the difference is that Northern's calculator is assuming higher levels of residual CO2 in the beer post fermentation, so calling for less sugar to get a specific number of volumes.
Brew on
Silver_Is_Money
Larry Sayre, Developer of 'Mash Made Easy'
I assume you specified the same sugar in both cases, yes? Did you specify dextrose (corn sugar) or sucrose (cane/beet sugar)? Most dextrose is actually dextrose monohydrate, so it requires ~10% more dextrose monohydtrate than pure dextrose to carbonate to the same level. Might Northern's calculator be calculating based on pure dextrose?
The more probable cause for the difference is that Northern's calculator is assuming higher levels of residual CO2 in the beer post fermentation, so calling for less sugar to get a specific number of volumes.
Brew on
In assessing the 9% difference I looked in all cases at both corn sugar and granulated white table sugar, and I strictly compared apples to apples and oranges to oranges. I have no idea what these programs look like internally. Just as for you, I can only use them, I can't dissect them. Brewer's Friend shows us its estimate of the volumes of CO2 present before priming, but Northern Brewer does not, so a comparison on this basis is not possible.
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