Kinetics of pepsin-induced hydrolysis and the coagulation of milk proteins

• DOI: 10.3168/jds.2021-21177
• Publication Date: 2022-01-05T22:46:01Z
• Authors: Mengxiao Yang; Aiqian Ye; Zhi Yang; David W. Everett; Elliot Paul Gilbert; Harjinder Singh
• Keywords: Pepsin

Hydrolysis-induced coagulation of casein micelles by pepsin occurs during the digestion milk. In this study, effect pH (6.7-5.3) and concentration (0.110-2.75 U/mL) on hydrolysis κ-casein in bovine skim milk was investigated at 37°C using reverse-phase HPLC, oscillatory rheology, confocal laser scanning microscopy. The followed a combined kinetic model first-order putative denaturation. rate increased with increasing given pH, dependent, reached maximum ∼6.0. Both increase decrease resulted shorter time. extent required for independent and, because lower electrostatic repulsion between para-casein decreased markedly from ∼73% to ∼33% when 6.3 5.3. addition, rheological properties microstructures coagulum were affected concentration. knowledge obtained study provides further understanding mechanism coagulation, occurring initial stage transiting into gastric conditions high low