« on: October 14, 2010, 07:55:12 AM »
I do the same thing.
The enzyme portion's already been covered.
DMS: as already stated, you're safe.
hop isomerization: you will continue to get some hop isomerization and break down of the essential oils of your aroma hops, I have noticed this, it's not horribly bad, and usually only add my aroma hops once I've begun to cool.
the beer overall, clarity, etc, I have no idea if this is detrimental to it or not. I do have issues with clarity, but I've always had issues with clarity before I started doing the recirc. I haven't had any issues with overall flavor or head retention.
And now to hijack the thread as well: my whirlpool lacks much whirlpool foo. I do 10g batches. The inlet to the keggle is at the top, I do have some copper bits to get it further down, into the wort by at least 4 inches or so (avoid hot side aeration as much as I can) and I do notice *some* circular motion, but not much, and I rather doubt just how effective it is, as at the end, I still have a fairly uniform amount of break and hop material across my false bottom. I try to stir it up and help the whirlpool out, but not to much effect.
So I'm curious as to how much movement you see, what pump you're using how far up/down your inlet is in your kettle, and what's the height difference between the top most point of your inlet and your pump. Me, I've got a march pump (I forget the model, the basic non-self-priming ones), pumps through the morebeer chillzilla which is maybe a foot above the pump, into the kettle which is probably another 3-4 feet up.