Aerating after adding yeast

What are the effects of aerating after yeast? I was moving too fast tonight and realized that I forgot to aerate until after I added the yeast already.

I really don’t think you will have a problem…just aerate it now and you will be fine

I’ve done a few times you will be fine. If it was dry yeast then there is no need to aerate.

It was dry yeast, what is the difference in the need to aerate?

If it’s within an hour or so, I don’t think there should be a problem as you’re still well within the growth phase of the fermentation.

I’ve recently taken to shaking, then pitching the yeast, then aerating with a diffusion stone for half an hour. The hope is that I can get some of the benefit of oxygenating past 8ppm by replenishing the oxygen that the yeast might take up over the course of that first half hour. So far I haven’t had any problems with it, though I also haven’t been doing it for too many batches yet.

I believe dry yeast has glycogen reserves so aeration is less critical…but with liquid it takes a little more nourishment in the start of fermentation to help develop strong cell walls

I believe dry yeast has glycogen reserves so aeration is less critical…but with liquid it takes a little more nourishment in the start of fermentation to help develop strong cell walls[/quote]

Correct,

With dry yeast you have up to 5.0% glycogen/sterol reserves when pitched, So O2 becomes a non issue as the reserves are high enough. Now in common practice when using a “liquid”-slurry of any type you will always be reserve glycogen/sterol deficient at the end of any/all brewing cycles and need to bring O2 levels up in starters/wort to encourage growth of glycogen/sterol reserves for efficient budding-low occurrence of petite mutants during fermentation. Even when using O2 in brewing slurry you will usually never see higher than around 1.0% glycogen/sterol reserves with “wet” yeast.

And to tack onto the main question->It will not harm your beer in any way if you added yeast and then aerated. To follow up on the above and how you made your current beer the O2 added will be consumed during respiration so it doesn’t hurt to add air to wort pre or post pitching dry yeast. But can be skipped also per the explanation above unless your using a “wet” slurry.

If using wet yeast you would also be fine adding O2 pre or post pitching yeast. As this is the still in the time-frame. (IE: 1-24 hours of the respiration phase.)

The only negative time to add O2 is after fermentation has started or finished as this would then oxidize your beer prematurely.

they answered the question for me. I have pitched dry yeast lots of times and never aerated because of like stated above. Only time you need to aerate dry yeast is when you’re repitching from a previously fermented batch.