Characterization of duck egg white gel under the action of baijiu (Chinese liquor)

In this paper, the changes of physico-chemical characteristics, microstructures and secondary structures of duck egg white (EW) gels under the action of baijiu (Chinese liquor) were studied via the texture analyzer, environmental scanning electron microscope (ESEM) and Fourier transform infrared spectroscopy (FT-IR). Results showed that the hardness, centrifugal water holding capacity (WHC) and surface hydrophobicity of the EW gels increased gradually with the pickling time. ESEM indicated that the EW gels exhibited an increasingly compact network structure. The ionic bond and disulfide bond took the leading role in maintaining the gel network. SDS-PAGE showed that lysozyme disappeared first, and other proteins except ovomucoid disappeared gradually. The absolute value of zeta potential reached the maximum on the 8th day and then decreased slightly. The overall trend of α- helix, β- turn, β- sheet and the random coil in the secondary structure of the gel increased.