Food allergies are considered as the sixth problem of human health by the World Health Organization. The number of people with symptoms of allergic reactions to food and the severity of these symptoms continues to increase in the recent years. From the top six listed food allergies, Cow Milk Allergy is one of the third positions with about 9% of the total number of diagnosed cases. Milk allergy symptoms vary from one patient to another and often include gastrointestinal symptoms, such as nausea and diarrhea. The dairy proteins and their relationship with allergic reactions have been intensively studied. ?-lactoglobulin is the most abundant milk proteins composed of 162 amino acid residues, which is classified in the lipocalin family sharing common secondary and tertiary structures and the ability to bind small hydrophobic molecules. It is also the most allergen protein in the mammalian milk. In this book, it has been discussed the effects of mutation, heat denaturation and the moderate glycation of bovine ?-lactoglobulin on its structural, binding and allergenicity properties. Several linear epitopes present in the ?-lactoglobulin recognized by IgE were identified and discussed.