Hydrolysates are proteins digested into smaller fragments, peptides, and its sole building blocks, the amino acids. A hydrolysate is therefore a blend of different peptides and different peptide lengths. In the hydrolysis process, we start with the intact protein, for instance whey or casein, which is digested by enzymes into smaller fragments. The hydrolysis process influences the peptide size. Depending on the level of hydrolysis, we are able to obtain mildly hydrolysed, partially hydrolysed or extensively hydrolysed proteins. Moreover, the peptides can be filtered, in order to obtain a mixture with very small peptides and no larger fragments.