Priming sugar

[EvanAltman36]

I am thinking about cold crashing my IPA to get more of the hop residue and other stuff out of suspension prior to bottle carbing. However, the calculator I've used takes temp into account and calls for less sugar to be used at the lower temp, specifically about 50% less for the batch if I've got it at 40 degrees rather than at ambient temp. I would think it'd be the opposite, that the crash would drop some of the yeast out, thus requiring a little more sugar. Or is it because using the same amount of sugar at lower temps would result in residual sugar in the beer?

 

[LarryBrewer]

At a lower temp, more CO2 is dissolved in solution. Think of it this way - heat drives off the gas.

You'll still have plenty of residual yeast to consume the priming sugar.

I recently bottled an IIPA at 40F in the shed, and I used less sugar, but I also targeted a slightly higher value for 'volumes of CO2' to hedge (2.3 instead of my typical 2.0). Carbonation is great, and actually could be less. So, in short - do use less sugar when packaging at low temps.

 

[EvanAltman36]

Excellent, thanks! Follow-up question. If I cold-crash a beer that's fermenting in a Better Bottle, am I going to have trouble with the sides sucking in? Or can I rig the airlock somehow to make sure nothing gets sucked in as the temp drops and the pressure reverses?

 

[LarryBrewer]

The airlock chamber will simply flip so the pressure is indicated in the opposite direction. I'd doubt any of it makes it back into the fermentor.

 

[flars]

Will the beer be at 40° when you bottle or will the temperature be rising to room temperature as you are bottling? If the temperature will be rising you could be better off to let the temperature of the beer rise to ambient temperature and use the ambient temperature for calculating the amount of priming sugar.

 

[EvanAltman36]

I'm sure the temp will rise to some extent during the process. I'm going to move right from the crash to the bucket and bottle from there, so I'm sure it will rise. But in checking Larry's post, I think it's a safer bet to stick with the calculations for a lower temp, or even estimate it at 50 or so, in order to not over-carbonate. When it comes to an IPA, I would prefer to end up around 2.0 and not up higher at 2.4 or something.

 

[Kevin The Stout]

Evan, how did that batch turn out?

I would expect it to be under carbonated. The residual co2 in the beer depends on the temperature of the beer when active fermentation ceased. If you cold crash the beer even though co2 solubility is increased you don't add any more co2 to the beer.

Would you agree with this Larry? If so, the wording on the priming calculator is a bit misleading.

 

[LarryBrewer]

Evan, how did that batch turn out?

I would expect it to be under carbonated. The residual co2 in the beer depends on the temperature of the beer when active fermentation ceased. If you cold crash the beer even though co2 solubility is increased you don't add any more co2 to the beer.

Would you agree with this Larry? If so, the wording on the priming calculator is a bit misleading.

Interesting point. In theory there is also CO2 in the headspace inside the carboy, and that will dissolve back into solution, maybe not to saturation levels though.

When the bottling temp is low I've been adding 0.2+ volumes to compensate / hedge my bets. The beer has been turning out sufficiently primed.

 

[EvanAltman36]

Evan, how did that batch turn out?

I would expect it to be under carbonated. The residual co2 in the beer depends on the temperature of the beer when active fermentation ceased. If you cold crash the beer even though co2 solubility is increased you don't add any more co2 to the beer.

Would you agree with this Larry? If so, the wording on the priming calculator is a bit misleading.

I had mixed results, though I think that was more to do with my own failures during the bottling process due to not being very thorough. I cold crashed both my IPA and a Fat Tire clone kit that I got from my LHBS. I think the CO2 levels and the sugar measurements were fine, but I didn't account for the fact that a colder liquid is far less able to keep additional stuff in suspension. As a result, I didn't get a very good mix of priming sugar into the beer, which resulted in uneven carbonation throughout my batch. The flavors were really good (I'm actually posting on that in another thread shortly), but I ended up with several flat bottles. I've been stirring very gently throughout the bottling now and also using PET bottles at regular intervals in order to get an accurate idea of how the batch is carbing throughout. I've also not cold-crashed after that either because I didn't get a noticeable difference in clarity for my troubles.

 

[Foster82]

I think the CO2 levels and the sugar measurements were fine, but I didn't account for the fact that a colder liquid is far less able to keep additional stuff in suspension.

Are your dissolving your priming sugar in a 200-250ml of water (about 1 cup). If so I wouldn't think you would have a mixing problem regardless of temp. Bringing the water to a boil will ensure the sugar is completely dissolved, even with 5 oz of sugar.

To help ensure I get a good mix, I added the priming mixture to my bucket then coil some of the hose from my racking cane in the bottom of the bucket, which generates a nice swirling effect as I transfer the beer. I then gently sir with a wide straining spoon (its about 3 inches in dia) right before bottling for approx 1/2 a min and call it good. Never had a problem with this method to date.

 

[EvanAltman36]

Yep, I do exactly that. But it's easier to incorporate anything into suspension the warmer the liquid is. You can stir Hershey's syrup into cold milk but it'll dissolve quicker and easier into warm milk. Long story short, some of the bottles are fully carbed, even overly so, while some were flat. While I didn't mark the individual bottles, I'd bet plenty of money that the carbed-up bottles were from the bottom of the bucket. I know that it had to be an issue of incorporation of the simple syrup because I had some over-carbed and some with very little carbonation. Had they been uniformly under-carbed, it'd be an issue of too little sugar. At the end of the day, I'd have been better off to cold crash in order to drop debris out of suspension, then bring the temp back up bottle. No issues since then though, so I'm not concerned about it; I allow the racking beer to stir itself but then gently circulate it with a long stirrer at intervals throughout the process.

 

[Foster82]

Now that you mention it I do allow my brew to return to room temp after a cool crash before bottling.

 

[Nosybear]

I bottle it at whatever temperature the is at when I decide to bottle, then store it at the temperature of my basement (about 65°) to condition. Seems to come out about the same regardless of what temperature the beer is at bottling. I think - and have no data to back this up - that the temperature at bottling has less to do with the final result than the temperature the beer is stored during conditioning. And I have to admit, this has always confused me about the calculator - it refers to the temperature at packaging, not the storage temperature through secondary which seems to me to be the more important temperature.

 

[LarryBrewer]

Now that you mention it I do allow my brew to return to room temp after a cool crash before bottling.

I do as well, bringing it up to counter height (usually means sitting on top the fermentation chamber), and letting it sit there at least a few hours for everything to settle back out. Overnight is ideal. That said, a few packaging nights this year were pretty cold and it was around 45F in the shed.

 

[EvanAltman36]

The temp during conditioning needs to be enough for the yeast to be active enough to eat the sugar and create the CO2 to carbonate it, but the bottling temp will determine how much CO2 is in the beer, and thus, the amount of sugar required to create the additional needed. At the end of the day, you're fine as long as the sugar is mixed well. Mine wasn't, which is why 1 batch had some well-carbed and some flat bottles. I do like the idea of using PET bottles at regular intervals while bottling so that I can tell by feel how the carbonation process is going and make sure that they're all at the same level.