Gelation of chicken pectoralis major myosin and heat-denatured beta-lactoglobulin.
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 71 degrees C. Thermal denaturation patterns of myosin and myosin/HDLG were similar except for the appearance of an endothermic peak at 54-56 degrees C in the mixed system. At pH 7.0, 2% myosin began to gel at 48 degrees C and had a storage modulus (G') of 500 Pa upon cooling. Myosin/HDLG (2% total protein) had a gel point of 48 degrees C and a G' of 650 Pa, whereas myosin/beta-LG had a gel point of 49 degrees C 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.
Vittayanont
Manee
M
Department Food Science and Human Nutrition and Center for Advanced Microscopy, Michigan State University, East Lansing, Michigan 48824-1224, USA.
Steffe
James F
JF
Flegler
Stanley L
SL
Smith
Denise M
DM
D000818:Animals; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002645:Chickens; D005782:Gels; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007782:Lactoglobulins / Q000737:chemistry* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D018482:Muscle, Skeletal / Q000737:chemistry*; D009218:Myosins / Q000737:chemistry* / Q000648:ultrastructure; D011202:Poultry Products; D011489:Protein Denaturation; D012212:Rheology; D013816:Thermodynamics
D005782:Gels; D007782:Lactoglobulins; D009218:Myosins