100% Pure Mixes Instantly Microfiltered High in Branch Chain Amino Acids Natural Unflavored All Natural - No Aspartame, No Sucralose, No Acesulfame-K Voted 2005 and 2006 Whole Foods Magazine ?Best Sports Supplement? NOW? Whey Protein Isolate is a high quality protein supplement that is both bioavailable and easily digested. Whey protein contains a high concentration of Branched Chain Amino Acids (BCAA's), which are important for efficient muscle metabolism. These qualities make NOW? Whey Protein Isolate an ideal supplement for active individuals. Whey protein is considered to have the highest Biological Value of any protein source - superior in essential amino acid content to beef, milk, casein or soy.