What is your finished dough temperature? Too high of a finished dough temperature can result in excessive acid formation in the dough. Typically, we see temperatures of 65 to 70F used where long cold ferment periods are employed. That said, if you still want to reduce the acidity of the dough you might include a buffer in the dough as an ingredient. Calcium is an excellent buffer, so you might look at using calcium sulfate, or even something as basic as milk or yogurt which are good sources of calcium. The calcium will buffer the acid formation, making for a less acid dough in the long run. This is why antacids such as Tums contain calcium.
Tom Lehmann/The Dough Doctor