Bread seems less sour
I've got a 67% hydradation starter that has been going about 7 months now, and lately, it seems less sour than it used to. Some background:
Mother lives in the fridge full time and gets fed once or twice a week as needed.
She gets 3 parts flour to 2 parts filtered water to 1 part starter at feeding time.
I feed half all trumps high gluten and half king arthur whole wheat.
I bake about 16 loaves a week.
About 3 weeks back, I dropped the mother I was using and cracked shattered the plastic container. For the sake of safety, I through out my big container. I keep 4 oz of emergency back up, which was about 1 month old at the time. I built up the mother from that (I keep about 24 oz on hand). The leavening power is still there, the starter smells like it did. I'm doing a two stage build (same recipie as always). 4 oz mother gets built to 30 oz of in between starter, then the next day the 30 oz gets is used to make about 2.8 kg of dough. At both stages, the rise is really good for a wild yeast starter. Final bread has a nice texture, nice crust, but isnt' real sour.
So what should I do to get some of the sour flavor back? My recipe doesn't use a ton of mother, but it is the same one I always used. Do I need to change my feeding schedule for a while? Change what I'm feeding for a while (started with rye, could feed a few times with rye) . Other suggestions are welcome.