I might be getting my bacterias confused, but isn't there a lot of lacto on the grain itself? It seems like you could keep a little grain and not mash/boil it, then add that grain to the wort.
Uff Da Picobrewery
Primary: Arrogant Bastard Clone, Pumpkin Ale
Kegged: Marble Red Clone, Cream Ale, PilsAle, Cider
Bottled: Yule Gruit, Unhallowed BGSA (10-10-10), Nymphetamine Barleywine (999)