Abstract: To elucidate the colour stability of pork,oxymyoglobin was extracted at 24h post mortem and purified from semimembranosrs of pork.After seperation from metmyoglobin by chromatography on DEAE-Sepharose FF and Sephadex G-75 columns,its purity was controlled by SDS-PAGE electrophoresis and scanning spectrophotometry.The autoxidation rate was measured over a wide range of pH values(5 0～7 0),temperatures(20～50℃),ionis strength(0～600mmol/L NaCl) and partial pressure of O2(0～150mmHg).The results showed the exogenous factors(pH,temperature,ionic strength and partial pressure of O2) had significant effects on the autoxidation rate of oxymyoglobin•Low pH,high temperature,high ionic strength and very low partial pressure of O2 could increase the autoxidation rate.

Key words: Pork Pxymyoglobin Purification Exogenous factor Autoxidation