San Francisco Bread

San Francisco's water is soft, with low mineral content and minimal alkalinity. For bread, and for sourdough in particular, this matters. Soft water produces a more extensible dough: one that stretches rather than tears, which is what you want when you're working with the long, slow fermentations that define San Francisco sourdough.

The connection between San Francisco and sourdough is partly about the water and partly about the wild yeast and lactobacillus cultures that thrive in the local environment. But the water plays its role. Low mineral content means less interference with gluten development, and low alkalinity means the natural acids produced during fermentation aren't buffered away. The dough stays acidic, which gives the bread its characteristic tang.

If you're baking sourdough and want that open crumb, chewy texture, and sharp flavour, soft water helps. Hard water tightens gluten and buffers acidity, both of which work against the style. San Francisco's mineral profile won't give you San Francisco's wild cultures, but it gives the dough the right conditions to develop properly.