It is a 5% solution of lactose in water with lactalbumin and some lipid content. They have been isolated from human hair, lactalbumin, and feathers. It is a 5% solution of lactose in water, with some minerals and lactalbumin. Dairy-sourced protein ingredients include casein, caseinates, whey and lactalbumin, among others. Lactalbumin is found in the milk of many mammals.