Abstract:Duck egg white protein（DEWP）was phosphorylated by dry-heating in the presence of pyrophosphate.The antioxidant activity of DEWP，including ABTS+free-radical scavenging capacity，superoxide anion radical scavenging activity and Fe2+chelating capacity，was then investigated before and after phosphorylation by dry-heating in the presence of pyrophosphate.Furthermore，the effects of phosphorylation on structure of DEWP were identified by spectra fluorescence，infrared spectra and circular dichroism spectra.The results showed that the antioxidant activity of DEWP was slightly increased after heating in a dry state.The results showed that the secondary structure and solubility of DEWP were almost unaffected under the effect of dry-heating phosphorylation，but its antioxidant activity and heat stability were significantly enhanced.The increased antioxidant activity of DEWP after dry-heating phosphorylation was mainly due to the introduction of phosphate groups and the increase of the surface SH content.