The addition of baking SODA to the dough does a couple of things. It raises the pH of the dough, making it more alkaline, and thus lowering the yeast activity slightly. It also increases the rate at which the crust color develops, as well as giving a slightly different crust color, and the soda affects the flavor of the finished crust too. I’ve seen soda used in some of the older formulas/recipes but not much use in the more modern ones. I think where the use of soda originated was in the use of soda to make certain types of crackers (soda crackers). These are dry and crispy and some enterprising individual insearch of a crispy pizza decided to try adding soda to his pizza dough. Does it work? Well…it does affect the color of the crust as well as the flavor, but not the crispiness, that comes from the special ovens that crackers are baked in. The amount of soda used is normally in the range of 0.5 to about 1% of the flour weight. It is normally added right along with the flour. If you add too much soda you can saponify the fat/oil in your dough giving it the wonderful flavor of Ivory, or perhaps, Dial (soap). Make sure you use BAKING soda and not WASHING soda. Lastly, baking soda is not the same as BAKING POWDER, we’re talking about baking SODA here.
Tom Lehmann/The Dough Doctor