Antigenic response of bovine β-lactoglobulin influenced by ultra-high pressure treatment and temperature

beta-lactoglobulin (beta-1g), the main whey protein fraction in bovine milk, is one of the first antigens encountered by a newborn child, and it is the major allergen causing cow's milk allergy. High pressure (HP) treatment causes changes in the protein structure and may influence the antigenity of beta-1g. Whey protein isolate solution (WPI), sweet whey and raw skim milk were pressurized and the antigenic response of bovine beta-1g was analysed by means of an indirect competitive enzyme-linked immunosorbent assay (ELISA). In addition, the degree of denaturation of beta-1g was determined by means of high pressure liquid chromatography (RP-HPLC). The different solutions containing beta-1g were pressurized at 200, 400 and 600 MPa for 0, 10 and 30 min at temperatures between 30 degrees C to 68 degrees C. In all solutions, the antigenity of beta-1g increased with increasing pressure and with holding time. In combination with thermal treatment (40, 50 degrees C), the antigenity of beta-1g increased, but higher temperatures (60, 68 degrees C) caused a decrease of the antigenity of beta-1g, but the initial value was not reached. The measured increase in degree of denaturation did not correlate with the antigenity of beta-1g. (c) 2006 Elsevier Ltd. All rights reserved.