Abstract:To explore the method and mechanism of pH-shifting-induced refolding modification of the porcine liver protein（PLP），and to lay the theoretical foundation for the high-value development and utilization of porcine liver.The solution of porcine liver protein was treated with pH-shifting（pH3-11）and then adjusted to neutral.After lyophilization，the solubility，emulsification activity，emulsion stability，surface hydrophobicity，emulsion size，Zeta potential，active sulfhydryl groups，endogenous fluorescence spectra，and infrared spectra of the modified porcine liver protein were measured. The results showed that the solubility，emulsification activity，and emulsion stability of PLP decreased after acidic pH-shifting treatment，the emulsion particle size increased and the absolute value of Zeta potential decreased，while the alkaline pH-shifting treatment increased the solubility and emulsification activity and emulsion stability of PLP，and the emulsion particle size decreased and the absolute value of Zeta potential increased. The fluorescence intensity and active sulfhydryl content of PLP decreased after modification，indicating that the pH-shifting treatment had a significant effect on the tertiary structure，while the infrared spectroscopy results showed that it had less effect on the secondary structure. The alkaline pH-shifting treatment can effectively improve the functional properties of porcine liver protein such as emulsification and solubility.