In my troubleshooting my mozzarella failures (http://cheeseforum.org/forum/index.php/topic,12290.0.html
), I had a basic science question that dawned on me, that I can't find the answer to. And trust me, I've been looking and reading and searching...
My curds weren't getting acidic enough.
Does citric acid convert lactose to lactic acid? Or does it just add acid and therefore drop the pH? Therefore, after cutting the curds and raining the whey, there would not be additional acidity?
Conversely, I imagine that using a culture (in this case, thermo, as others have done), would be more active and create more acid -- until it is stopped (salting, for example).