Wort foaming during O2 aeration

[user 199714]

Hello all,

I used an O2 aeration system (using .5 micron stone and 'pure' filtered oxygen) on a batch I stared two evenings ago. Fermentation started at the 24 hour mark and ramped up well at 48 hours. No problem there.

My issue was with the degree to which the wort foamed up. I do use Starsan (I do not fear the foam...) but I do let as much of the foam from the primary drain out as possible, so I'm having a hard time blaming the Starsan.

Am I turning up the oxygen too much? Should it be at a "rolling boil" or just minor bubbling from the stone?

Any input greatly appreciated.

 

[Natdavis777]

Turn the O2 on just to the point where it you see the bubbles coming from the stone (I use my wand and press the stone against the glass to verify). I originally was cranking it 100% on and it was churning wort like butter. It also started overflowing wort foam out of the carboy within 30 sec. I was then informed by some people here I was doing it wrong. It also explained why I was only getting 3 batches (10 gal) of beer on one of the red oxygen tanks. Now I have tanks lasting a lot longer and am able to give a good 90 sec burst without foam "foaming" out

 

[gregkeller]

Good advice above. If you see bubbles coming off the stone, and none getting to the surface, then that is perfect because the 02 is dissolving into solution. If you get bubbles to the surface, then you are wasting oxygen. Also the colder the wort is, the more oxygen you can dissolve in solution, so I usually chill to 2-3 degrees below my initial fermentation temp to try and get a little more oxygen into the wort.