I got a pack of Wyeast 3789 Trappist Blend at my LHBS and I'm trying to figure out what to do with it besides make an Orval clone and I'm leaning towards sours these days. I know it has Sacc. and Brett in it, but no souring bacteria. So...would adding the dregs from a bottle or two of unpasteurized sour beers work to make something like a Petrus Sour Pale Ale? Or should I go ahead and add pure bacterial cultures? Thanks in advance for your advice!