Ghost Whey Protein Powder for $50 (2.2 pounds): Ghost is the protein powder for people who want their post-workout snack to taste like dessert. Its protein blend includes whey concentrate, casein, milk protein isolate, whey protein isolate, hydrolyzed whey isolate, and micellar casein, so you get a mix of fast and slow-digesting proteins. Whey protein: Whey protein comes from milk during the cheese-making process, and it’s one of the most efficient ways to get protein into your system. Whey protein hydrolysate: Whey protein hydrolysate is predigested using enzymes, making it the quickest to absorb. Casein protein: Casein is the other major protein in milk.