| Three parts were included in this paper: (1) The extraction, purification and identification of myosin from skeletal muscle of Pasoas major (PM) and Semimembranosus proprius(SMp) of male rabbit. (2) Effect of myosin concentration, pH, ionic strength, heating temperature, poly-phosphates and divalent metal ions on the turbidity and solubility of myosin was studied. (3) Effect of myosin concentration, pH, ionic strength, heating pattern, heating temperature, the addition of polyphosphates, divalent metal ions, non-meat proteins, polysaccharides, transglutaminase on heat-induced gelation strength was studied. Results of the study are outlined as:(1) The myosin was extracted, purified and identified from PM and SMp of male rabbit. The concentration of purified myosin was about 20-30 mg/mL, the rate of extraction was 1%. Four bands in the purified myosin showed in SDS-PAGE analysis, which were assigned to the myosin heavy chains (MHC) and myosin light chains according to their relative molecular weight, their relative molecular weight are 205KDa, 25.9KDa, 17.8 KDa and 13.8 KDa, respectively.(2) The absorbance of myosin at 340nm was used as the criterion of turbidity and the concentration difference of myosin before and after the centrifugation as the solubility. The influence of various factors on turbidity and solubility was studied. The result showed that the effect of myosin concentration on turbidity was linear. The turbidity increased with the temperature and PM myosin reached the maximum at 55 degree while SMp myosin at 60 degree. The solubility decreased when the temperature increased. The turbidity reached its maximum at the pH of 5.5 with ionic strength of 0.6M KC1. The solubility increased significantly when the pH value was over pH 5. The turbidity increased while the solubility decreased when the ionic strength decreased. At high ionic strength (0.6 M KC1) the turbidity increased and solubility decreased with sodium pyrophosphate (SPP) and trimeric sodium phosphate (TPP) addition, but the converse was got with the sodium hexametahposphate (HMP) addition, which mean solubility increasing and turbidity decreasing. With low ion strength, low concentration (0.25%) of SPP could improve the turbidity of myosin, but high concentration SPP (0.75%) would decrease the turbidity, however, TPP decreased the turbidity, low concentration TPP (0.25%) improved thesolubility while high concentration TPP (0.75%) decreased the solubility, low concentration HMP (0.25% for PM myosin, 0.5% for SMp myosin) decreased the turbidity and high concentration (0.75%) improved the turbidity, the solubility didn't improve until the concentration of HMP reached 0.75% at the ionic strength of 0.2 M KCl. The addition of CaCl2 or MgCl2 improved the turbidity, and CaCl2 improved the solubility but the decreased the solubility. In sum, processing condition (such as myosin concentration, pH, ionic strength, temperature etc) and addatives (such as poly-phosphates, metal ions etc) affect the turbidity of myosin solution and solubility of myosin.(3) Effect of various factors on heat-induced gelation strength was studied. The results showed the effect of myosin concentration on heat-induced gelation strength was linear, the optimal pH forming gelation was pH 6.0 for PM myosin, pH 5.5 for SMp myosin at the ionic strength of 0.6 M KCl. In the pH 6.0 buffer solutions, the gel strength was improved with the increasing of ionic strength, and reached the maximum at the ionic strength of 1.0 M KCl for PM myosin and 0.6 M KCl for SMp myosin. Gel formed by linear-heating had greater strength than isothermal only when heating period was 10 minutes for PM myosin. Result indicated heating pattern had no effect on gel strength for SMp myosin. The optimal temperature forming gelation is 60 degree. The addition of SPP and TPP to myosin solution would decrease the gel strength, and HMP increase the gel strength. The gel strength increased significantly (p<0.05) with 10mM MgCl2 for PM myosin and 12mM MgCl2 for SMp myosin or 8mM CaCl2 for PM myosin a...
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