What is whey protein - EXPLAINER VIDEO Whey protein is a mixture of globular proteins isolated from whey , the liquid material created as a by-product of cheese production. Whey protein is commonly marketed as a dietary supplement, and various health claims have been attributed to it in the alternative medicine community. B-Nergetics 100% Whey Premium Protein Powder, Chocolate Extreme, 5lbs, 5.6g Bcaa, Boosts Lean Muscle Growth and Recovery from B-Nergetics