Correct. Sourdough is wild yeast (usually Saccharomyces exiguous) and lactobacillaceae. Today's commercial yeast is usually Saccharomyces cerevisiae (instant,

Correct. Sourdough is wild yeast (usually Saccharomyces exiguous) and lactobacillaceae. Today's commercial yeast is usually Saccharomyces cerevisiae (instant, active dry, . The leaven you talking about is called "mother dough", basically a chunk of dough from previous baking. I find the article wanting. To make sourdough starter one needs water, flour, and time. That is it.