What is Instant BCAA? Instant BCAA from BULK POWDERS™ is an easy to mix BCAA powder; providing an optimal 2:1:1 ratio of Leucine, Isoleucine & Valine. BCAA is an abbreviation of branched chain amino acids. As part of our Pure Series™ range you can be assured that these BCAA are of the highest quality available, but at the lowest price. What's more, our flavoured varieties taste absolutely simply delicious – we truly believe you won't find a better tasting flavoured BCAA product