Cold crashing

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You put your fermenter in the fridge for a few days. This caused anything still in suspension to drop to the bottom, clearing the beer. Its not required, but some people like the additional clarity it provides.
 
It is essentially a technique used to clear your beer. You take the beer and chill it to a temp too cold for the yeast. They then go dormant and drop out of suspension making for clearer beer. It's not required.
 
In addition to yeast, cold crashing takes proteins out of suspension and clears the beer. The best effect is dropping the temp in excess of 6 degrees in under 6 hours. A terminal temp of 38-42 is also preferable. You'll need temp control to do this. Ice in a bathtub won't usually cut it.

But if you get set up for cold crashing, you'll probably find yourself set up for lagering, and that opens up a whole new world of fun.
 
When cold crashing, should you wait until your beer is fully fermented, or when it is close to fermented?
 
Yea, you want to wait until its fully fermented, because you'll stall the yeast when you cold crash. You want to do this a few days just prior to bottling. Take the fermenter out of wherever you're cooling it then begin your bottling process.
 
When cold crashing, should you wait until your beer is fully fermented, or when it is close to fermented?

Fully fermented plus some (3 to 5 days with properly pitched and fermented beer) so the yeast have a chance to clean up and condition before you force them dormant.
 
Only thing I will add is to be careful with your priming sugar if you carbonate naturally. Cold water holds more CO2 - if you bottle it cold (right out of the fridge), you need to reduce the priming sugar. If let it warm up before bottling, no problem.
 
jsv1204 said:
Only thing I will add is to be careful with your priming sugar if you carbonate naturally. Cold water holds more CO2 - if you bottle it cold (right out of the fridge), you need to reduce the priming sugar. If let it warm up before bottling, no problem.

Good advice to avoid bottle bombs. Question: if you let it warm up, don't you undo most of what you accomplished with the cold crash in the first place?
 
No, because the things you don't want have already settled to the bottom of the carboy. Just try not to shake it up too much when moving it around.
 
Only thing I will add is to be careful with your priming sugar if you carbonate naturally. Cold water holds more CO2 - if you bottle it cold (right out of the fridge), you need to reduce the priming sugar. If let it warm up before bottling, no problem.

I don't understand this thinking here. The CO2 production is determined by the amount of priming sugar used. AFAIK, the temp. doesn't affect the amount of CO2 the yeast produces, just possibly the time that it takes to carb up in the bottle.

As long as you don't add so much sugar that the CO2 production will result in too many volumes of CO2 and excessive head space pressure, you should be fine.

I may be misinterpreting your post.
 
OG2620 said:
I don't understand this thinking here. The CO2 production is determined by the amount of priming sugar used. AFAIK, the temp. doesn't affect the amount of CO2 the yeast produces, just possibly the time that it takes to carb up in the bottle.

As long as you don't add so much sugar that the CO2 production will result in too many volumes of CO2 and excessive head space pressure, you should be fine.

I may be misinterpreting your post.

I think he's saying that that if you bottle cold (~34dF) then you let the bottles condition warm (~70dF) the beer you put in originally will expand and you'll be left with less head space and more pressure.

My napkin math at work says that 12oz of water at 34= almost 12.5oz at 70. I bottled a Boston ale clone cold about a month ago, and ended up with some very fizzy beer, no bottle bombs though.
 
Has anyone had any problem bottle prime-carbonating beer that had been cold crashed? As in there wasn't enough yeast left in the beer to eat the priming sugar?
 
Jayhem said:
Has anyone had any problem bottle prime-carbonating beer that had been cold crashed? As in there wasn't enough yeast left in the beer to eat the priming sugar?

No, that's not really an issue, there are trillions of yeast in your beer, and it only takes a few to eat through your priming sugar. you'd have to do a lot more than cold crash to get them all out, it's why the megabreweries spend the big bucks on filtering and pasturizing.
 
OG2620 said:
I don't understand this thinking here. The CO2 production is determined by the amount of priming sugar used. AFAIK, the temp. doesn't affect the amount of CO2 the yeast produces, just possibly the time that it takes to carb up in the bottle.

As long as you don't add so much sugar that the CO2 production will result in too many volumes of CO2 and excessive head space pressure, you should be fine.

I may be misinterpreting your post.

I think the issue is that the yeast continue to work when cold. Then the CO2 they produce is more likely to be held in solution with the beer (same reason you store in the fridge a few days to get CO2 into solution). Then you have more in the beer to start with, so you may over prime.
 
Once that the beer it´s fermented doesn´t produce any more co2, I have bottled cold and didn´t have any problems with bottle bombs or overcarbed beer. When you calculate your priming sugar you account the highest temperature of your beer during fermentation or conditioning to know how much residual co2 your beer has.
For example: I bottled a pale ale three weeks ago, that beer was in primary at 68F for 12 days, move it to secondary for 5 days to dryhop at room temp (at that time was around 75F), after that I cold crash it for 2 days an bottled cold. I accounted a fermentation temp of 75F (the highest temperature the beer sat) and calculate the priming sugar for that temp an not for the current temperature of the beer (40F at bottling time). The co2 that it´s released at higher temperatures doesn´t magicly goes back to your beer if you cool it. I had no bottle bombs or overcarbonation problems i bottle all the time and have done this (or something similar) with last 10 batches. I found no problems with beer expanding neither. I think I don´t understand what everybody is saying or I must be very confused.
 
Obliviousbrew said:
Once that the beer it´s fermented doesn´t produce any more co2, I have bottled cold and didn´t have any problems with bottle bombs or overcarbed beer. When you calculate your priming sugar you account the highest temperature of your beer during fermentation or conditioning to know how much residual co2 your beer has.
For example: I bottled a pale ale three weeks ago, that beer was in primary at 68F for 12 days, move it to secondary for 5 days to dryhop at room temp (at that time was around 75F), after that I cold crash it for 2 days an bottled cold. I accounted a fermentation temp of 75F (the highest temperature the beer sat) and calculate the priming sugar for that temp an not for the current temperature of the beer (40F at bottling time). The co2 that it´s released at higher temperatures doesn´t magicly goes back to your beer if you cool it. I had no bottle bombs or overcarbonation problems i bottle all the time and have done this (or something similar) with last 10 batches. I found no problems with beer expanding neither. I think I don´t understand what everybody is saying or I must be very confused.

I think that you are absolutely right. So if anything, you'll need more priming sugar if you fermentation temp got pretty high at some point on your process due to the loss of residual carbonation.
 
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