yeast under pressure

Hi! yesterday i did an APA batch using US05 everything pretty nice, dump my rehidrated yeast on a SS conical fermentor at 4 pm.

The problem is that my blow off tube has a valve to prevent oxidation when i transfer my green beer to another vessel.

I checked fermentation today at 3 pm and there wasnt any sign of bubbles. I checked the valve and it was closed. So all the CO2 where inside the fermentor. I am worried of possible change in flavor or poor yeast activity because of being in pressure with all that CO2 for several hours (23). Is that possible? thanks for your answers. The beer now is fermenting at positive rate and flavor at now is good enough.

By the way, is an APA initially fermented at 60 and raised to 64F

thanks again!

Too much pressure can damage the yeast, but some breweries ferment under some pressure to minimize ester development. Sounds like you probably caught it in time to save the batch, and the tank (assuming you don’t have a pressure reliefe valve).

so…asssuming its an APA it would be a benefit to prevent esters? :smiley: i do this recipe regullarly and the first 24 hours are really slow…so i think there wasn’t “a lot” of CO2 (i hope)

Conicals aren’t built to operate under any significant amount of pressure, so you really shouldn’t close it off and build up unregulated pressure. Your PRV (assuming there is one) is not a regulator/Spunding valve.

BTW - ponied up the dough for a conical, but not investing in liquid yeast?