Diacytl rest.

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Jeepsn beer

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Is Co2 produced during diacytl take up by yeast, Or is CO2 only produced during fermentation.
 
Anyone,anyone? What I'm trying to decide is the perfect time for giving my Pilsner a warmup diacytl rest. I waited till all bubbling and pressure were gone, then warmed it up to rm temp. It started bubbling again, is this further fermentation or does yeast produce co2 upon reconsuming diacytl. I will see if my hydrometer readings change I guess. I hate dipping hydrometers excessively. Anyone, anyone? good question, dumb question?
 
I have never done a lager but may I can help some, usually a diacytl rest is done before fermentation is complete, I believe at 75% to FG. So yes, I think CO2 would still be produced. Also, when you raise the temperature, CO2 is less soluble in the beer so CO2 will be released in the manner too. Either way, it is not abnormal.
 
CO2 is always produced during fermentation, although you may not see active bubbling. The purpose of a D-rest is to have the yeast consume the not-so-yummy buttery popcorn taste (diacytl) so you get a nice clean taste from the pilsner. If it's been at room temperature, take a reading when it first warms up, then another at least two days later.

So why does it matter if CO2 is made during fermentation or the D-rest? You should be lagering when fermentation is complete anyways, so the beer should be in a clearing carboy with airlock on it anyways.
 
I am more interested in the biology of it. My lagering process consists of 3-4 weeks of primary lagering at 45 degrees until bubbling stops completely and fg is achieved. Then I raise temp for 48 hours to speed up Diacytl recovery (this is when I get renewed bubbling). Then it goes in the fridge at 35 degrees for as long as I can stand not drinking it. The point made about CO2 solubility at differant temps makes sense, I didn't think of that. As for now, I'll assume yeast don't produce anything when diacytl is reconsumed. Thanks
 
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