Maintaining Sourdough Starter - Are potato flakes/water necessary? I just got some sourdough starter going with the Oregon Trail, and it seems to be doing quite well. However, the guide calls for using potato flakes or potato water to feed it- having neither, I hoped for the best and used some arrowroot powder instead. I'm not sure what the purpose of the potato stuff is- is it just food? I figured it might be primarily for providing starch, in which case the arrowroot should be fine.
I feed sourdough starter with strong white bread flour mixed with water to make a sloppy dough. This is a common method in the UK and it seems to work well.