I don't know why, but my sourdough starter is becoming less and less acidic with time. It still has great rising power - it will double the size of a loaf in a few hours. I retard my loaves in the refrigerator overnight after two rises in the hopes of developing better flavor as well as some sourness, but it doesn't seem to do anything. Also, the starter has developed a strange acetone scent which completely disappears in the bread dough.
Here's my process:
-use about 4/5 of my starter making bread
-replenish the starter up to 5/5 with flour and water
-refrigerate it until I bake again the next week
Anyone have any ideas? Also, does the decrease in acidity of the breads mean that they are not as nutritious as truly sour breads? Or is it the process of fermenting with the natural sourdough yeasts that break down the flour and make it more digestable? Thank you for any help you might offer!