Whey hydrolysate is a third type of whey protein that is rarer to find in a day to day protein powder than isolate or concentrate. From a specifically scientific definition, whey protein hydrolysate is a partially digested; as in the basic molecules in whey protein are broken down into its baser parts, essentially doing part of the work of regular digestion for you.
Generally whey protein hydrolysate is significantly more expensive to purchase 
compared to concentrate or isolate, however whey hydrolysate, due to its processed nature, also contains less lactose. Also for anyone who has stomach issues, the body has a far easier time digesting hydrolysate than it does other forms of whey protein powder.
One of whey protein hydrolysate main uses is in baby milk for babies that are born severely lactose intolerant and unable to use regular high fat and protein milk sources. Also due to its sterile nature after processing, it is often used as a high protein supplement for patients after digestive surgery to restore a proper PH balance in the digestive tract.
Basically by breaking the whey protein into its base parts, it allows the body the same nutrition and essential amino acids that regular protein powder would provide, while preventing any of the potential dietary side effects that some people have.
Whey hydrolysate can be found at Amazon here: Gaspari Nutrition MyoFusion With Hydrolysate, Strawberry And Cream, 2-Pound
MyoFusion is probably the best known and most popular whey protein hydrolysate manufacturers around. It has exceptionally high bioavailability, meaning your body is using every last nutrient available to it.
