Temp used for residual CO2?

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wiescins

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I use the priming sugar calculator at TastyBrew (http://www.tastybrew.com/calculators/priming.html) to determine how much to add. My question is what temperature do I use when entering fermentation temperature? I generally keep the primary in the mid low 60's for the first week or 2, then let it rise to high 60's by then end of the 3rd week, finally I'll cold crash it down to low sixties prior to racking. Do I use the temp at which most fermentation occurs, or do I use the temp beer is at when bottling?
 
Use the temp that the beer will be at when you're bottling it.

No, use the highest temperature the beer reached during the end of fermentation or later. Cold crashing doesn't create more co2- co2 is only created during fermentation. More co2 exits the fermenter through the airlock at warmer temperatures, and that's what the calculator is looking for- the probable amount of dissolved co2 based on fermentation/post fermntation temperature.

For example, when I make a lager, I ferment at 50 degrees, do a diacetyl rest at 62 degrees (and you should see the airlock bubble then, from raising the temp!), and then it's lagered and kept at 34 degrees until it's bottled. That means my temperature for calculation purposes is 62 degrees, as that is when much of any residual co2 would have been released. Hope that makes sense!
 
No, use the highest temperature the beer reached during the end of fermentation or later. Cold crashing doesn't create more co2- co2 is only created during fermentation. More co2 exits the fermenter through the airlock at warmer temperatures, and that's what the calculator is looking for- the probable amount of dissolved co2 based on fermentation/post fermntation temperature.

For example, when I make a lager, I ferment at 50 degrees, do a diacetyl rest at 62 degrees (and you should see the airlock bubble then, from raising the temp!), and then it's lagered and kept at 34 degrees until it's bottled. That means my temperature for calculation purposes is 62 degrees, as that is when much of any residual co2 would have been released. Hope that makes sense!

very helpful, thank you!

Just to make sure I fully understand...Initial fermentation is held at 62, then as it slows temp is raised to 68 until completion and then some, cold crashed down to 58 for 1 day, racked to secondary, held at 68 for 2 weeks, cold crashed down to 58 for 1 day, racked to bottling bucket, beer warms 70 in bucket prior to bottling. In this scenario, I would use 68. Am I good?
 
very helpful, thank you!

Just to make sure I fully understand...Initial fermentation is held at 62, then as it slows temp is raised to 68 until completion and then some, cold crashed down to 58 for 1 day, racked to secondary, held at 68 for 2 weeks, cold crashed down to 58 for 1 day, racked to bottling bucket, beer warms 70 in bucket prior to bottling. In this scenario, I would use 68. Am I good?

Yes, that's what I'd!
 
very helpful, thank you!

Just to make sure I fully understand...Initial fermentation is held at 62, then as it slows temp is raised to 68 until completion and then some, cold crashed down to 58 for 1 day, racked to secondary, held at 68 for 2 weeks, cold crashed down to 58 for 1 day, racked to bottling bucket, beer warms 70 in bucket prior to bottling. In this scenario, I would use 68. Am I good?


Actually, you would use your bottling temperature of 70F. But it is not a huge difference either way.
 
i made a stout and it fermented at 74 degrees but is currently sitting at 70 degrees. would i use the 74 number for the calculator since it was the highest or would i use the 70 which the beer is currently sitting at to get the correct amount priming sugar for volumes of co2? thx
 
i made a stout and it fermented at 74 degrees but is currently sitting at 70 degrees. would i use the 74 number for the calculator since it was the highest or would i use the 70 which the beer is currently sitting at to get the correct amount priming sugar for volumes of co2? thx

74 degrees, but there shouldn't be much (if any) difference in the amounts you'd use. I'd use 4 ounces of priming sugar for 5 gallons.
 
okay thank you my fermentor is reading that it has 21 liters in it and didnt know how to do the math since tastybeer says 3.5 ounce for 70 degrees n 3.6 for 74 degrees but that thats for 5 gallons. i was trying to make 6 gallons and had a problem with one of my fermentors so i had to switch and it was less than it should be. im rounding it off as 5 gallons since im going to try and not get so much sediment in the bottle as possible. i was thinking of 4 ounces of brown sugar or table sugar for the batch but wasnt sure and all the calculators ive looked at give different numbers.
 
okay thank you my fermentor is reading that it has 21 liters in it and didnt know how to do the math since tastybeer says 3.5 ounce for 70 degrees n 3.6 for 74 degrees but that thats for 5 gallons. i was trying to make 6 gallons and had a problem with one of my fermentors so i had to switch and it was less than it should be. im rounding it off as 5 gallons since im going to try and not get so much sediment in the bottle as possible. i was thinking of 4 ounces of brown sugar or table sugar for the batch but wasnt sure and all the calculators ive looked at give different numbers.

Brown sugar is different, and I don't know the conversion for that. But for table sugar, that's no problem. It's a little more fermentable, but with 4 ounces total used, the difference is negligible.
 
i was told to treat brown sugar the same as sucrose since it is the same but with the addition of molasses. thats the only reason why im confused. i might just use table sugar but i thought the brown would make the beer taste better after bottling. Also northern brewer shows 3.5 ounce for a 5 gallon batch at 74 degrees and brown sugar 3.94 at same type of batch. at those figures brown sugar wouldnt be treated the same as standard sucrose. I've never took these things into thought before. But now i am it might help to produce a better beer.
 
i was told to treat brown sugar the same as sucrose since it is the same but with the addition of molasses. thats the only reason why im confused. i might just use table sugar but i thought the brown would make the beer taste better after bottling.

Well, it's not the same as sucrose- at least not really. I wouldn't chance it unless you knew the fermentability. But the flavor impact would be negligible anyway, as you're talking about such a tiny quantity anyway that I don't think there would be any taste difference at all in brown sugar/honey/table sugar/corn sugar/maple syrup as priming sugar. Thats 4 ounces of sugar (simple sugar, at that) in 5 gallons. That may be 2% or so of the fermentables, so you won't get any flavor from that.
 
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