Antibody mediated allergy to Cow's milk can form a major threat to the infant's health. Infants with this type of allergy cannot consume normal milk from cow origin. Cow’s milk-derived whey hydrolysates are nutritional substitutes for children with this type of allergy. These hydrolysates can be regarded as degraded proteins of which the fragments will no longer to be recognized by the immune system of the allergic child. Cow's milk (or more specifically whey) hyrolyses therefore, will not trigger an allergic reaction. For the safety of the infant it is important to assess any residual allergenicity of the hydrolyses, before using these in infant food.