It really doesn't matter so long as you aerate right before or right after. I prefer before.Dave
If you are using compressed, filtered air then it is probably best to do it before and after if you can. If you are using pure o2 you should not aerate after you pitch the yeast because pure o2 is toxic to yeast. I have actually killed starters with pure o2 by aerating after pitching.
Up to tomorrow morning's brew my aeration method has been to whisk for 5 minutes with a 22" whisk. I just bought an aeration stone and wand (for filtered air, not o2, though I could upgrade easily). Thanks for the insight; I don't know if I will ever use o2, but if I do, I'll heed your advice.
The big difference between compressed air and 02 is time. 1-2 minutes o2 is all you need as opposed to 20 minutes or so with regular air.
I'm starting to think I might like Belgian ales with filtered air better than pure o2. Pure o2 seems to leave less ester profile behind.
Quote from: majorvices on December 23, 2013, 10:44:25 AMThe big difference between compressed air and 02 is time. 1-2 minutes o2 is all you need as opposed to 20 minutes or so with regular air.Right. I just haven't seen any performance difference for the additional investment in the O2 regulator and the cost of the tanks.Not a huge investment, but also one I could have just as easily not made and still been pretty much where I'm at fermentation-wise. It is another gadget, though, which has some value in and of itself.