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Having read a cold crashing thread here I wondered if its ok to plunge yeast into almost freezing temperatures for a week or so and then expect it to crack on and consume another sugar meal when bottled as if nothing has happened? I’ve read posts talking about killing yeast if pinched at over 26 degrees or more, so assumed it was temperature sensitive and that a lower extreme could prove fatal too?
 
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Pitching at 26C won’t kill your yeast, it’ll just cause off flavours. You need temperature of about double that to kill it.

It depends what you mean by “near freezing”. Plenty of us cold crash without issue, and I usually take mine to about 2C. I accidentally froze some of my beer last brew in the cold crash and it still carbed fine.
 
Nothing to worry about, the yeast just goes dormant then when it warms up it wakes and starts fermenting again. You will lose alot of the yeast as it will settle to the bottom of the FV but there will be plenty left to carb the bottles.
I cold crash to 0.5C and 2 weeks in the bottles they always carbed up nicely.
 
If you bottle warm your bottles will carb up in a few days. If you cold crash it'll take a couple of weeks - not because you've killed yeast but because you will have clearer beer with much fewer yeast cells floating about.
I usually bottle warm but you do then end up with more sediment in the bottles - not really a problem if you use a sticky yeast like gervin or SO4.
 
Ok, thanks everyone. Now I understand it better. I built a brew fridge at the very start so I could probably do this pretty easily. How long do you usually cold crash for?

Hi, here’s my experience. I used hop spiders and bags when dry hopping so no need to cold crash. This means more yeast makes it into the bottles and with no drop in temperature the yeast starts to act on the priming sugar straight away. Bottles are carbonated in 2-3 days if you leave them at room temperature, but best to leave them for a week. Before drinking put your bottles in the fridge overnight or longer to drop the yeast and clear the beer and they’re good to drink. You do get a noticeable amount of sediment but the chilling makes it stick to the bottom and doesn’t come out when pouring. I have now moved onto to kegs and force carbonization. I don’t use spiders or bags anymore so I cold crash at 2.5C for 48 hours and it’s amazing how all the green matter drops to the bottom. If you are bottling you need to let the temperature rise to room temperature for 7-14 days to let the yeast ferment the priming sugar. Less sediment with this method but it takes longer and perhaps doesn’t carbonate as well in my experience.
 
I’ve cold crashed for weeks, then bottled and they carbonated fine. They are resilient little things.
 
This is all really helpful, thanks. It has, however, left me with a bit of a dilemma. I’ve got a Bulldog brews standard IPA kit on at the moment. My plan was to dry hop with 100g Citra pellets in a muslin bag for a couple of days before bottling it. I’m now wondering if I should just chuck the pellets in and cold crash instead!?
 
I think it’s reasonable to expect less aroma will reach the beer of you use a bag or spider as it will contain the hops and retain some of the aroma and oils. On the plus side you don’t really need to cold crash and get drinkable beer quicker. If you chuck hop pellets straight in, as I do, you will need to cold crash for at least 48 hours. You should get a better effect from the dry hops as they are in full contact with the beer, but expect a longer time to carbonate as more yeast will drop out of suspension and not reach the bottle. Overall if you’re not in a rush put the hops pellets straight in, cold crash down to 2 degrees for the last couple of days at least, on bottling day syphon the beer to a clean sanitized bottling bucket, add the priming sugar, dissolved in boiling water, and then bottle. Leave bottles at room temperature for 7-14 days then they can be stored, chilled etc. You can attach a muslin bag to the syphon to catch any green matter but with a 48 hour cold crash I find I don’t need to do this because the vast majority sinks to the bottom.
 

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