Originally Posted by Freezeblade
I think that the "buttered" flavor would actually be the yeast throwing out a bit of diacetyl, which you can be remedied by bringing the fermenting beer up in temp for a rest at normal ale temps, just like you would for a lager.
I've often wondered if that is the case, because I don't brew lagers really, so I haven't really nailed down the diacetyl taste. However, like permo, I ferment my Kolsch-yeast beers cold but once they get to about .010 to .007 from their anticipated FG, I ramp them up to something in-between 65 and 70 (let the apartment's room temp decide) and I still get the flavor. I feel it's just a yeast characteristic. I know New Glarus uses White Labs or Wyeast Kolsch strain for their Spotted Cow, and I notice this flavor in that beer as well.