Beta-lactoglobulin is the major whey protein in bovine milk, comprising approximately 50-60% of total whey proteins. It is a globular protein belonging to the lipocalin family, featuring a beta-barrel structure that enables binding and transport of small hydrophobic ligands such as fatty acids, retinol, and flavor compounds. With a molecular weight of about 18.3 kDa, it exists as a dimer at neutral pH and monomer at acidic pH. It plays roles in nutrition, emulsification in food processing, and as a potential allergen. Heat denaturation above 70°C leads to aggregation and gelation properties useful in food texture. It is highly soluble in water at pH above its isoelectric point (pI ~5.2) and contributes to the nutritional profile of dairy products.