Sourdough for Beginners

Every type of bread needs a leavening agent. For quick breads, it’s baking powder or baking soda. For yeasted breads like sandwich bread, it’s, well, yeast, in the form of commercial yeast that’s either fresh in cake form, or dried in the form of quick-acting active dry yeast or instant yeast. For sourdough bread, the leavener is a culture born from the microorganisms and good bacteria that are naturally present in wheat flour. With the right combination of time, temperature, and hydration these microorganisms create the culture necessary to leaven bread. They also create a distinctive tangy aroma due to the acids in the bacteria. This is what gives sourdough its signature flavor.

You may be underbaking it, and there’s a foolproof way to know when your bread is done. You may have seen people knocking on the bottom of a loaf of bread to check for doneness, but the most accurate test is using an instant read thermometer. Depending on the type of bread you’ll be looking for something around the 200 degree mark. If your bread still comes out gummy you may not be cooling it long enough. Cutting into a warm loaf often yields a gummy center as the starches are still setting up.

Those cuts and patterns on the tops of loaves sure do look nice, and that is definitely part of their appeal, but they also have a practical function: as the dough bakes it expands, so it will rupture or break through the crust. A cut in the surface of proofed bread creates weak spots in a loaf’s surface and allows the interior crumb to expand fully in the right direction. Without the slashes, the loaf will expand outward wherever it finds a random weak spot, resulting in an oddly shaped loaf and an uneven crumb. Traditionally the slashing is done with a tool called a lame, but any very sharp knife or razor will do the trick.

Once the flour is hydrated your starter begins to transform: the yeasts and bacteria in the flour freely multiply and the mixture transforms into its own unique culture. At this point the starter is a living, breathing thing and needs just the right environment to grow healthy and robust. This means precise temperature, time, hydration, oxygen, and food. You feed the nascent culture by adding fresh flour and water to provide a new supply of nutrients to the starter. As it becomes mature it will need less frequent feedings, but at first it’s pretty delicate and needs to be babied a bit!