I stir the crap out of it in the kettle as it cools with the IC.
Based on what I've read, agitating the wort after the boil (before it chills to 80°F or less) leads to hot side aeration and accelerated staling. There is some debate on this, but I did this for my first few batches in order to cool it faster, and all those batches staled quickly. (And when I say "staled quickly," I mean went from tasting "good" to "not good" within a couple months.) Also, stirring while chilling exposes the cooling wort to airborne bacteria and wild yeast, which can lead to infection. I've created a few bottle bombs and sour gushers this way, despite meticulous sanitation.
I suspect it takes quite a bit, though, given the amount of "HSA is a myth" talk.
If you are having a lot of infections from airborne bacteria or wild yeast, you are most likely working in an environment with too much dust. They need something to ride, and that something needs to land in your beer/wort.
I don't see a flow meter...
Here is a link to an OLD brew strong podcast with a UC Davis professor.
http://s125483039.onlinehome.us/archive/bs_hsa1-26-09.mp3
Standard O2 welding oxygen gauge and valve for welding. Its that brass thing at top (gauge and valve not visible in first photo so here it is! A manly solution) Easy to control.![]()
Yep, that's good old Charlie Bamforth, and he said the same thing in BeerSmith podcast #74. You said it very well: he "put HSA in it's place" relative to all the other things the homebrewer should be concerned about. My only point was that stirring an open kettle of wort while it chills is an opportunity for bacteria/yeast infection or oxidation (or both) to get into your beer, so why take a chance? Probably the bacteria and wild yeast risk is higher, as most people boil and chill outside or in their garage where airborne particles carrying these organisms are more prevalent. (Perhaps I should have just said it that way to begin with. D'oh.)
I thought about this and we now use a Duda Diesel Chiller and go directly from whirlpool to putting in a Fermenter. I can pump 180 degree wort at full throttle in to a Fermenter at 64 degrees in the winter (Dallas Area). In the summer I use chilled water. Less chance for Bacteria