This product contains starter cultures mixed with organic rye flour. Mix with water and follow the procedures for making sourdough (periodic feeding). Sourdough is a dough containing a lacto bacillus culture that functions symbiotically with certain yeasts. Sourdough bread is made by using a small amount of starter dough, which contains the culture, and mixing it with new flour and water. Part of the resulting dough is then saved to use as the starter for the next batch. As long as the starter dough is fed flour and water continuously, the sourdough mixture can stay in room temperature indefinitely and remain healthy and usable.