Walk into any bakery today and you'll see the word "sourdough" stamped on everything from loaves to pizza crusts to bagels. It's become shorthand for "artisan" or "better," but the term actually describes a specific process, not just a flavor.
It starts with wild fermentation
Most bread relies on commercial yeast, a single cultivated strain added directly to the dough to make it rise quickly and predictably. Sourdough skips that shortcut. Instead, it's leavened by a "starter" — a mix of flour and water that's been left to ferment until it captures wild yeast and lactic acid bacteria naturally present in the flour and the air around it.
That starter is a living culture. Bakers feed it regularly with more flour and water, and over time it becomes strong enough to leaven an entire batch of dough on its own, no packaged yeast required.
Why it takes longer
Wild yeast is slower and less predictable than commercial yeast, so sourdough needs a long, slow fermentation — often many hours, sometimes over a day or two — instead of the quick rise you'd get with a packet of active dry yeast. That extra time is doing real work: it's what develops the deeper flavor and the characteristic texture people associate with sourdough.
What that means for pizza dough
The same principle applies when sourdough is used for pizza instead of bread. A long fermentation gives the dough time to develop flavor and a more open, chewy crumb once it hits a hot oven, rather than the flatter, more uniform bite of a same-day commercial-yeast crust.
It's a slower way to make dough, but it's also the traditional one — long before commercial yeast existed, this was simply how bread and dough were made.