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General Category => Yeast and Fermentation => Topic started by: skyler on August 30, 2011, 05:13:52 PM

Title: Oxygenating wort
Post by: skyler on August 30, 2011, 05:13:52 PM
Yesterday I forgot to aerate my wort. I brewed a 5.5 gal batch of a 1.050 hoppy rye ale (3.5 lbs 2-row, 3.5 lbs munich, 3 lbs rye malt, and 3 oz carafa special 3 added at sparge - mashed at 152F for 60 min). And my IC got it down to 68F, then I transferred it into the fermentation freezer (set to 34F) and dropped it down to 54F before pitching a large starter's-worth of first-generation pacman. Normally I would have aerated the wort just before I pitched the yeast, but this time I forgot. When I went to check on the beer this morning (12 hours after pitching), I could see no signs of activity (I lifted the top of the bucket to be sure, and there was nothing). That was when I remembered that I had not aerated the wort. So I decided to aerate at this point - believing that the oxygen added at this point will be effectively consumed by the yeast and will not be added too late to aid in yeast health and fermentation perfection. The temperature of the wort has remained at 54F (my plan is to ferment at 56, so I will be dropping the temperature on the chest freezer as soon as the wort starts actively fermenting). Am I wrong here? Would you guys have done the same thing?
Title: Re: Oxygenating wort
Post by: tschmidlin on August 30, 2011, 05:16:29 PM
I would have done the same thing.  I might have checked the gravity just to make sure, but I'm confident it will be fine.
Title: Re: Oxygenating wort
Post by: euge on August 30, 2011, 06:09:05 PM
If it was a large enough pitch then you really don't need to oxygenate. At least that's how I understand it.
Title: Re: Oxygenating wort
Post by: Pinski on August 30, 2011, 06:35:49 PM
Isn't 54F a really cool pitching temperature for an ale yeast?
Title: Re: Oxygenating wort
Post by: skyler on August 30, 2011, 06:37:04 PM
It was a 1.5L stir-plate starter that I decanted and then added another 1L of wort to, then stir-plated again before decanting. I would say there was about 3/4 inch of bright white yeast on the bottom of the flask, so I am almost certain it was a substantial pitch for this size beer. I love how clear my starter wort gets when I use pacman. It is really amazing how well this strain flocs out.
Title: Re: Oxygenating wort
Post by: skyler on August 30, 2011, 06:41:19 PM
Isn't 54F a really cool pitching temperature for an ale yeast?

Yes, but pacman is almost like an Altbier yeast when it comes to temperature. It was only when I started fermenting super-cold with it that I began to appreciate pacman as a strain. I like it best when fermented in the mid-high 50's. I know Rogue ferments most of their beers at 60F, but they use huge fermentation vessels, and I understand that the larger the fermenter, the higher the acceptable fermentation temperature...
Title: Re: Oxygenating wort
Post by: hoser on August 30, 2011, 06:45:46 PM
I would have done the same thing.  I might have checked the gravity just to make sure, but I'm confident it will be fine.

I agree. The reason you oxygenate is to build up the sterols in the cell walls.  By creating a starter on a stirplate you did this to some degree already.  You should be fine.