High-pressure Proteolytic Digestion of Food Proteins: Selective Elimination of β-Lactoglobulin in Bovine Milk Whey Concentrate

Abstract

Milk whey concentrate was subjected to digestion by thermolysin under a hydrostatic pressure of 1000-3000 kg/cm² to selectively remove the β-lactoglobulin involved. According to an analysis by electrophoresis with Polyacrylamide gel containing sodium dodecyl sulfate, the globulin was well digested by the reaction at 2000 kg/cm² and 30°C for 3 hr. The digest had no binding activity toward five kinds of anti-β-lactoglobulin monoclonal antibodies with distinct epitope specificity, while it contained the full content of α-lactalbumin. The result shows that moderately high pressures could be useful to control enzymatic proteolysis and to selectively digest the useless proteins contained in food.