Gelation of chicken pectoralis major myosin and heat-denatured beta-lactoglobulin

摘要

Thermal, rheological, and microstructural properties of myosin (1 and 2% protein) were compared to mixtures of 1% myosin and 1% heat-denatured beta-lactoglobulin aggregates (myosin/HDLG) and 1% myosin and 1% native beta-lactoglobulin (myosin/beta-LG) in 0.6 M NaCl and 0.05 M sodium phosphate buffer, pH 6.0, 6.5, and 7.0 during heating to 71degreesC. Thermal denaturation patterns of myosin and myosin/HDLG were similar except for the appearance of an endothermic peak at 54-56degreesC in the mixed system. At pH 7.0, 2% myosin began to gel at 48degreesC and had a storage modulus (G) of 500 Pa upon cooling. Myosin/HDLG (2% total protein) had a gel point of 48degreesC and a G of 650 Pa, whereas myosin/beta-LG had a gel point of 49degreesC but the G was lower (180 Pa). As the pH was decreased, the gel points of myosin and myosin/HDLG decreased and the G after cooling increased. The HDLG was incorporated within the myosin gel network, whereas beta-LG remained soluble.