What is a Bread Starter?

A bread starter is the base for many artisan breads, including sourdough and Amish Friendship Bread. It uses naturally occurring wild yeast as a leavening agent, lending a distinct flavor and texture to the bread that cannot be replicated by commercially harvested yeast. Some bread companies use starters that are over 100 years old to create dependably flavored bread every time. Many home bakers make their own starter as they explore the varied world of bread baking.

To make a bread starter, a baker begins with a mixture of flour and warm water that is set out in the open air to collect yeast. Sometimes, it takes several rounds of trial and error before yeast will appear. Bakers blend 1 cup (125 g) of flour with 1 cup (236.5 ml) of water to make a starter, setting it out in a warm place and covering it with a damp towel to keep it moist. Every 24 hours, the mixture is fed by the baker, who throws half of it away and mixes in 0.5 cup (62.5 g) of flour and 0.5 cup (118.2 ml) of water. Within a few days, the starter will begin to form a bubbly froth, which means that yeast is present and it can be used.

Once a starter has taken, it is usually refrigerated, which slows the growth of the yeast. When the baker is ready to use it, it is taken out of the cold and proofed. Proofing involves adding another cup (236.5 ml) of warm water and a cup (125 g) of flour to the starter to "wake up" the yeast and begin the fermentation process, which will result in bread. Depending on the yeast present in the bread starter, this proofed “sponge” may take two to 24 hours to become bubbly and edged with a white froth, indicating that it is ready.

To make bread, a small amount of the sponge is set aside and stored so that the baker has starter for next time. Then the ingredients of the bread, which can be as simple as water, flour, and salt, are mixed together to create dough. The dough is kneaded, allowed to rise, and baked. Most breads made from a starter rather than yeast have a more complex, slightly fermented flavor that many diners greatly appreciate.

It is easy to make bread starter and care for it. Some groups of friends or organizations exchange starter, as is the case with Amish Friendship Bread. Exchanging starters all over the world can allow bakers access to a wide variety of new flavors for their breads. Making a starter is also a fun way for children to learn about chemistry and baking.