PICKLING TIME AND ELECTRODIALYSIS AFFECTS FUNCTIONAL PROPERTIES OF SALTED DUCK EGG WHITE

Salted duck egg was prepared by coating fresh duck egg with laterite and sodium chloride. The effects of different lengths of pickling time and electrodialysis desalination on foaming, emulsifying and gelation properties of salted duck egg white (SDEW) were investigated. The pH was decreased from 9.3 to 7.1, zeta potential was decreased from -48.3 to -26.4 (mV), NaCl content increased from 0.49% to 7.32% and surface hydrophobicity increased from 177 to 372 (So/100 mg protein) after pickling for 8 weeks. After electrodialysis desalination treatment, the pH of SDEW was slightly increased and zeta potential was decreased; however, the NaCl content was reduced by 95% and surface hydrophobicity decreased by 30as, the SDS-PAGE pattern showed the same distribution of protein molecules. Electrodialysis desalination treatment did not affect emulsifying properties. The foamability and foam stability of SDEW decreased with increasing pickling time, but increased with electrodialysis desalination treatment. The gel strength of SDEW decreased with pickling time, but decreased sharply after electrodialysis desalination treatment.