I’ve stumbled on a procedure of aerating yeast before pitching into wort, and I was wondering if I’m crazy. After I decant the old wort off the starter, the first chilled wort out of the plate chiller goes on the yeast, then I put it back on the stir plate. It gets spinning at a fast rate while I finish running the rest of the wort into the carboy and aerated well. Then the yeast is pitched. It seams I’m getting a stronger, more vigorous fermentation. I have now data to back me up. Does this make sense?
I’ve heard a number of people claim that if you aerate the yeast there’s no (or less) need to aerate the wort.
Makes sense to me. How much chilled wort are you adding to your decanted yeast vs. the size of the starter. I would assume that the volume of chilled wort added is substantially larger than the size of the starter.
If the function of aeration is oxygen uptake by the yeast, I would think that however they get the O2 is insignificant, just that they get the O2 needed. So, it makes sense to me and it avoids putting too much O2 into the environment, which could happen with a large infusion of O2 by direct infusion with bottled O2 into a small container. I have no science behind this conclusion and for me, it is easier to simply use a drill with an aeration stick for a few minutes. YMMV, of course.
Ben Franklin?
I have heard this too. In reality I don’t think you HAVE TO aerate at all, but the health of the yeast may suffer in future pitches. It would still make beer though.
I would have no problem with this stir plate method if one used at least 2000ml, 5000ml would seem better. But id rather clean an O2 wand than a flask and stir bar.
Putting yeast with some wort on a stirplate seems like a great way to get a lot of oxygen dissolved. Even through it’s a small amount of wort, I could imagine the final oxygen level after diluting into the rest of the batch being pretty good. This would especially be the case compared to mediocre wort aeration methods. It could also be that the yeast have a chance to take up a lot of oxygen and are fully prepared to go.
kramerog - I’m not being precise, approximately equal to the size of the original starter.
I usually don’t use O2, just air via aquarium pump. Before I’d aerate the 5 gallons of wort after pitching the yeast, and it worked fine, but doing it this way seems to work much better for me. Now I’m leaving it on the stir plate as long as I can before pitching, maybe 45 minutes or so.