What is a yeast cake?

A yeast cake, also known as a sponge cake or a sourdough starter, is a mixture of flour, water, and yeast that is left to ferment over time. The yeast in the mixture consumes the sugars in the flour and produces carbon dioxide gas, which causes the cake to rise.

The process of making a yeast cake can take several days, or even weeks, depending on the recipe. The longer the cake ferments, the more complex and developed the flavors become.

Yeast cakes are used as a leavening agent in bread, cakes, and other baked goods. They can also be used to make sourdough bread, which has a distinctive tangy flavor.

To maintain a yeast cake, it must be fed regularly with fresh flour and water to keep the yeast active and healthy. Yeast cakes can be passed down from generation to generation, with each new batch incorporating some of the previous one's flavors and characteristics.