PrOatein Oat protein is a unique, patented natural protein concentrate from oats that can help manufacturers to meet the fast-growing consumer demand for nutritious, protein-enriched foods and supplements. PrOatein, like the oat grain it comes from, is rich in essential amino acids, including the desirable branched-chain amino acids which are important for muscle growth and recovery. Compared to other isolated proteins, it also has a great taste.