RED STAR Nutritional Yeast is a primary grown pure culture strain of Saccharomyces cerevisiae. It is a powdered yeast without leavening power, marketed for its protein and vitamin content. Nutritional Yeast is an excellent source of protein, rich in many of the essential amino acids that complement proteins available from other sources such as corn, wheat, and soy. RED STAR Nutritional Yeast contains an average of 50% protein by weight. RED STAR Nutritional Yeast is also a rich source of B-complex vitamins that are important for normal and healthy body functions.