Sun Jun 07, 2009 10:46 am
Channeling is not an issue when you batch sparge because every time you add more water you stir the whole mash up, recirc a few times, and drain the whole thing. Even if a channel does form, there is no difference in the gravity of the wort in the grist vs the wort in the channel. Also, you drain the whole thing, so gravity will eventually cause the wort outside the channel to drain out too.
Think of channeling this way- the sparge water (which has no sugar) punches through the grist forming a sort of "vertical river". It flows in from the top and comes straight out the bottom, without ever mixing with the rest of the wort. This leaves all the sugars off to the sides and lowers your extraction gravity. Stirring and draining during batch sparge turns this into a non-event.
HTH-
-B'Dawg
BJCP GM3 Judge & Mead
"Lunch Meat. It's an acquired taste....." -- Mylo