Effect of Maillard reaction products on the physical and antimicrobial properties of edible films based on ε‐polylysine and chitosan

Edible films based on Maillard reaction products (MRPs) of ε-polylysine and chitosan, without the use of any plasticiser, were prepared by solution casting. The effect of Maillard reaction parameters (reaction time and the ratio of polylysine/chitosan) of ε-polylysine and chitosan on the structure, moisture content, water solubility, total colour difference and mechanical properties of edible films formed by MRPs were systematically evaluated.Scanning electron microscopy confirmed that edible films prepared by the MRPs of ε-polylysine and chitosan through the Maillard reaction exhibited a more compact and dense structure than those from the mixture of biopolymers without the presence of MRPs. The tensile strength and % elongation values of films from the mixture were decreased significantly with the rise of ε-polylysine (P < 0.05). The moisture content of the films was not significantly affected by Maillard reaction, whereas water solubility was decreased and total colour difference was increased significantly (P < 0.05) with the extension of Maillard reaction time. In addition, antimicrobial activity of chitosan films against E. coli and S. aureus. could be achieved by incorporating ε-polylysine into chitosan.These films can ensure food quality and safety, especially for coating highly perishable foods, such as meat products. © 2014 Society of Chemical Industry.