Film characteristics of egg white protein Maillard reaction products and its coating effect on walnut rancidity

Egg white protein(EWP) is an important matrix for edible films because of its high nutritional value and good film-forming property.However,there are some disadvantages related to EWP film,such as low water barrier properties.In this study,EWP was glycosylated with xylose through Maillard reaction to improve its properties.The development of Maillard reaction of EWP and xylose was optimized based on contributions of sugar type,pH,heating temperature and xylose concentration to the Maillard reaction.The EWP-xylose Maillard reaction products(EWP-Xyl MRPs) were used to prepare a novel film,and their film-forming property and water vapor permeability(WVP) were investigated in comparison with the EWP film.Furthermore,both of the EWP-Xyl MRPs film and the EWP film were used to coat walnuts,and their effects on walnuts acid value were also investigated.The results showed that the WVP of the EWP-Xyl MRPs film was approximately 24% lower than that of EWP film.Both EWP-Xyl MRPs and EWP films have made the acid value 30% lower than the control group.There was no significant difference between EWP-Xyl MRPs and EWP coating in reduction of acid value.