Rice flour has the ability to ferment easily, creating a wonderful base for delicious breads with a slightly sour flavor. Once made, the sourdough starter can be used over and over again. Replenish it each time it is used to nourish the yeast and keep the starter alive. As the starter gets older, the flavor will become tangier; baked products made with "aged" starters will have more sourdough flavor. The starter serves as the leavening so no additional yeast is needed.