German Brewing

In an effort to minimize as much O2 as I can, I've been trying to stir my mash very minimally; perhaps to the extreme . For those that have a process worked out, what amount of stirring is okay during the dough-in? I actually underlet so when the MLT is full, the grain is sitting many inches below the top of the wort.

For anyone that sparges, I have the same question for prior to sparging. Are you doing much stirring before lautering?

I underlet and use HERMs with a full perforated false bottom in the MLT and return under the surface of the wort. I rely solely on the recirculation to even out temperature in the grain bed. The pump causes a gentle negative pressure at the bottom of the grain bed which compresses it slightly (nothing like enough to get a stuck mash) so I hope that squeezes out any air pockets.

You've been stirring your mash very minimally, is there any reason to believe you need to do anything differently?

I give one gentle stir on dough in, and making sure to keep the grain underneath the water still.

What was your old malt? I took a 15% hit going from barke to best and the like.