Aeration Question, i think

mattmauriello · Jun 28, 2010

So, im making a DFH 60 minute IPA clone (or trying anyway), using about 13.3 lbs of 2-row and another 1/2 pound of amber. I pitched 2 vials of WLP001. Fermentation started before 12 hours, which is good, but a full week later its still bubbling away, about a bubble every 6 seconds, using a regular watter bubbler airlock on a 7 gal bucket (ale pail). I've never had a primary fermentation go for so long. I'm fermenting right at 68-70 F, I cooled my wort to < 75 after boiling.

here's my suspicion...
I let the wort drop from the outlet of my CFC right into the bucket (about a 1 or 2 foot drop depending on how fill the bucket is), which would aerate a little, but not much. then I placed the lid on, and gave it a couple quick shakes, but nothing really 'vigorous' as I was afraid of dropping the bucket and ruining my day. previously I had always used an IC to cool, and i would dump the pot through a strainer, which would aerate much better.

does it seem likely that since i may not have aerated enough, that my yeast haven't multiplied enough to work quickly? and if so so, how worried should I be? I planned to leave it for 2 weeks any way, then rack and add hops and let sit for another 5-6 weeks.

thoughts?

permo · Jun 28, 2010

I am not sure, but I think you may be on the right track, but fermentation temperature could have something to do with it as well. Low temp = longer time.

When I brew a big beer I oxygenate through a metal strainer and also use my mash paddle to work into a frothy foamy state, I get good results that way. You could also try olive oil....dipping a toothpick into the oil and dipping the oiled end of the pick into your beer...they say it works and you can skip aeration.

mattmauriello · Jun 28, 2010

i had never heard of that olive oil thing, but naturally it piqued my interest. give this one a read:
one hell of a thesis

Saccharomyces · Jun 28, 2010

RDWHAHB. Give it a few extra days on the yeast beyond what you normally would.. you didn't underpitch so you should be fine.

Splash method: 2-4 ppm O2
Shaken 5 minutes: 4-6 ppm O2
Aerated with a pump for 15 min: 8ppm O2
Pure O2 for 60 seconds: 12-18 ppm O2
Minimum recommended level: 12 ppm O2

I use a 2 micron O2 stone, best $60 I ever spent on brewing equipment.

Swordsman · Jun 28, 2010

That is extremely interesting. Don't have time to read through it all at work, but the abstract definitely piquied my curiosity as well.

mattmauriello · Jun 28, 2010

yeah, i always thought that oxygen was needed for the cells to reproduce. while true, it would be more accurate to say that the cells need oxygen to maintain healthy cell walls as they reproduce. this method changes that by allowing the yeast to absorb the lipids necessary from compounds in the olive oil. apparently they got new belgium brewing company to help with the controls and taste tests, and ultimately they said that long term flavor stability was greatly improved when olive oil was used, and there was no oxynation/aeration at any point in the brewing process.