Corny keg cold crash

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fuzzybee

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I have a couple of beers fermenting in 6 gallon torpedo kegs. They are each on a blowoff into starsan. At the end of fermentation, I'd like to cold crash these in place. Will there be a pressure reduction problem if I just pull off the blowoff? Should I hit them with some CO2 first? Or maybe put them on a spunding valve before fermentation is complete to build up some pressure?
 

day_trippr

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Your beer will likely contain somewhere around .6 to .8 volumes of CO2 at the end of fermentation. Assuming a reasonably "full" keg, that dissolved CO2 will allow you to simply seal the keg and crash it. Just like a can of beer, the CO2 will prevent the keg from collapsing as it cools...

Cheers!
 

wsmith1625

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Your beer will likely contain somewhere around .6 to .8 volumes of CO2 at the end of fermentation. Assuming a reasonably "full" keg, that dissolved CO2 will allow you to simply seal the keg and crash it. Just like a can of beer, the CO2 will prevent the keg from collapsing as it cools...

Cheers!
Along the same lines, I'm planning a kolsch and want to lager it in my keg. I ferment in a separate fermenter and do a closed transfer to my kegs. Does is make a difference if I lager under pressure or should I carbonate after lagering is completed?
 

odie

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After a few days when the blow off slows down, you can replace the gas poppet and just let it pressurize naturally before fermentation is complete. Either use a spunding valve, or replace the PRV with a low PSI PRV (the red ones are about 25psi). Or even just put a pressure gauge on the gas post and manually vent the PRV a few times.

If you are properly carbonated at your fermentation temperatures, cold crashing after will not drop the pressure enough to unseat the keg lid.
 
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