Cow's Milk (CM) contains approximately 30 potentially allergenic proteins among which casein and whey proteins seem to be most important regarding allergy to CM [1]. The casein allergens comprise four different proteins, alpha-S1, alpha-S2, and beta and kappa casein and have a molecular weight between 19-25.2 kilodalton (kDa). The most important whey allergens include beta-lactoglobulin (BLG; 18.3 kDa) which is the most abundant CM whey protein (≈65%). BLG is present in CM but also in milk of many other mammals, however not in human milk although minor traces might be detected dependent on the diet of the lactating mother. Minor allergen fractions present in