Aerating a big beer

[pdm1982]

I've been reading some older threads on here that talk about aerating a big beer a second time at approximately 12 hours after pitching the yeast. Everything makes sense to me but those threads generally discuss injecting O2. Since I don't have an injection system, I was wondering if it would be okay to use the stainless steel wand/wisk that I normally use after transferring to the fermenter. After 12 hours would the wisk be harmful or insufficient?

The reason I ask is that I'm getting ready to brew a 1.100+ beer. I've made a few in the past and had some attenuation problems. I'm trying to cover my bases and help the yeast out as much as possible.

Here are the threads I was referring to:
https://www.homebrewtalk.com/showthread.php?t=247850
https://www.homebrewtalk.com/showthread.php?t=71456

 

[ArcLight]

I've been reading some older threads on here that talk about aerating a big beer a second time at approximately 12 hours after pitching the yeast. Everything makes sense to me but those threads generally discuss injecting O2. Since I don't have an injection system, I was wondering if it would be okay to use the stainless steel wand/wisk that I normally use after transferring to the fermenter. After 12 hours would the wisk be harmful or insufficient?

You can do this but I offer a word of warning - there will be a lot of dissolved CO2 in the beer, and when you start mixing it, it will come out all at once.
So make sure you gently stir it up for a few minutes (I use a long plastic stirring spoon), to off gas as much dissolved CO2 as possible.
That's better for the yeast too.

 

[pdm1982]

I guess maybe I don't fully understand. Would gently stirring with a spoon get enough O2 back into the beer to be worthwhile?

 

[ArcLight]

I guess maybe I don't fully understand. Would gently stirring with a spoon get enough O2 back into the beer to be worthwhile?

Gently stirring will get the CO2 out.
Then you have to vigorously shake the fermentor to get O2 in.


If you don't off gas the CO2 and vigorously shake, you will possibly end up with a mess.

 

[day_trippr]

The whole point of the 2nd aeration philosophy is that 12 hours post-pitch on a truly big beer the yeast would still be in the growth phase.
If that's true, there won't be much dissolved CO2.
If not, and the yeast are already chowing down, I suspect the O2 wouldn't provide much benefit anyway...

Cheers!

 

[Calder]

You don't have to wait 12 hours. You can do it at 6 and 12 hours, or continuously for 12 hours if you wish. The thought is that the O2 does not stay dissolved in the wort, so re-aerating will help .... and big beers need as much help as it can get.

Don't worry about CO2 coming out of solution, fermentation should not have started. If fermentation has started, you really should not be aerating again.

 

[pdm1982]

So using a stainless steel wisk attached to a drill vs straight O2 injection should be fine? That's my only real question in all this.

 

[fun4stuff]

Pitch a large multi step healthy starter and there will be no need to aerate or oxygenate. Save yourself the headache.