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Author Topic: Oxygenated 12 hours before pitching yeast. Am I in trouble?  (Read 1753 times)

Offline Bilsch

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Re: Oxygenated 12 hours before pitching yeast. Am I in trouble?
« Reply #15 on: October 20, 2020, 09:34:00 am »
Contrary to your belief but not contrary to science fact. Oxygen is actually soluble at just the right amount that is recommended for yeast, about 8ppm at 20c. The oxygen will not off gas to the headspace but instead be consumed by the malt and hop antioxidants.


Offline RC

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Re: Oxygenated 12 hours before pitching yeast. Am I in trouble?
« Reply #16 on: October 20, 2020, 10:42:37 am »
Contrary to your belief but not contrary to science fact. Oxygen is actually soluble at just the right amount that is recommended for yeast, about 8ppm at 20c. The oxygen will not off gas to the headspace but instead be consumed by the malt and hop antioxidants.

It's not really belief, it's more the second law of thermodynamics. Above 8ppm, the extra oxygen will want to leave solution to achieve equilibrium. I honestly don't know how rapidly this happens but I'll speculate that 12 hours is enough time for this. But to your point, seems reasonable that a lot of that O2 would be intercepted by various reactions. Long story short, this wort probably had only ~8ppm, which, yes, is enough unless the yeast aren't very healthy and/or the wort is imperial strength, which we don't know from the OP. I guess my original point was that the extra oxygen, over and above ~8ppm, was likely not there.

Offline Lazy Ant Brewing

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Re: Oxygenated 12 hours before pitching yeast. Am I in trouble?
« Reply #17 on: October 20, 2020, 11:49:48 am »
To build on Mark's comment concerning microflora in the wort in every brewery I always remember the statement I learned long ago,
"Fermentation is a race between the yeast and bacteria.  You always want the yeast to win."  Although you are probably be OK, pitching right after aeration is always the best practice to make sure that the bacteria doesn't gain a foothold in your fermenter.

I recently was unable to pitch yeast until about 48 hours after aerating, but it turned out ok because to my untrained taste buds, the yeast outcompeted the bacteria and the beer tastes fine.
It's easier to read brewing books and get information from the forum than to sacrifice virgins to appease the brewing gods when bad beer happens!

Offline mainebrewer

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Re: Oxygenated 12 hours before pitching yeast. Am I in trouble?
« Reply #18 on: October 20, 2020, 02:47:02 pm »
Anyone else wonder where the OP went?
"It's not that people are ignorant, it's just that they know so much that just isn't true." Ronald Reagan