Aerate during fermentation

[ILMSTMF]

Hi,

I've got a big one planned for tomorrow with a target OG of 1090. EDIT - I'm re-pitching on half the harvested yeast cake from a freshly kegged 1.066 OG batch of the same size.
Chill the wort after boil, rack to FV (Fermzilla All Rounder). I use a huge whisk, clasped between palms, and "roll" it in the wort. Creates a notable amount of foam on surface. Pitch the yeast, seal it up, into the FC.

Looking to aerate / oxygenate post pitch, before very active fermentation gets underway. Being without an O2 kit, would sanitizing the whisk, opening FV lid, and stirring be the only / best way? Thanks in advance.

 

[Jaybird]

Personally I would pass on it. I personally don't open a fermenter once the yeast is in unless I am dry hopping or adding a finish yeast. But if you do go for it just keep things clean and sanitary and you'll be fine.


Cheers
Jay

 

[IslandLizard]

It's often advised when inoculating a high gravity wort/beer to perform a 2nd aeration/oxygenation 12-18 hours after the first one at pitching time. But to prevent oxidation issues, the 2nd O2 injection ideally has to be done before active fermentation has started, which can be difficult to time or gauge.

 

[fluketamer]

what they said why bother just let it ride.
jaybird hints at oxidizing issues and lizard says its a timing thing which means the risks probably outweigh the benefits.

 

[ILMSTMF]

I will need a concrete plan to consider going for that post-pitch aeration. In a perfect world, could do it with the lid sealed... but there's the still the issue of doing so at the right time!
Thanks all!

 

[day_trippr]

For a 90 point beer I'd focus on a respectable pitch rate (1m cells/ml/°P for instance), a good blast of O2 up front, then let it ride and not risk oxidation. I keep a 1.107 OG stout on tap using S04 and just following the above it invariably finishes between 1.017~1.023 so attenuation between 77~83%, which isn't shabby for that yeast with an advertised attenuation range of 74-82%

Cheers!

 

[IslandLizard]

Are you using that little "spray" gadget on the end of the racking hose when transferring the wort from the kettle to the fermenter? That would be a very decent way to aerate that chilled wort. The closer the wort is to your ferm temps during that transfer the better. Main reason, cooler wort (pretty much any normal liquid, really) can contain more dissolved oxygen than warmer wort/liquid.

Then you give the wort an extra aeration in the fermenter, right after the transfer.
You've got to move that whisk vigorously, making some foam. A mere gentle stirring isn't going to do much.

Needless to say, make sure your hands, and forearm that do the stirring above or inside the fermenter are clean and well-sanitized. Or better, wear a sanitized (silicone) glove or a sanitized plastic bag, taped up higher on your arm.

 

[pocketmon]

According to Dr. Clayton Cone, 14th hour into fermentation is the optimum time to add the oxygen.

https://hbd.org/hbd/archive/3301.html#3301-1

It is not practical, but the optimum time to add the oxygen is at about the
14th hour into the fermentation. The yeast have multiplied to the point that
the lipids are about depleted and the cells are hungry for oxygen . At this
point the yeast uses the oxygen more efficiently. That is why in commercial
breweries that require several preparations of wort to fill the fermenter,
the fermentations go so well. The second and third additions of oxygen rich
wort are added at the time that the yeast needs the oxygen the most.

In the Yeast book, it is suggested to add a second dose of oxygen between 12 and 18 hours.