Effect of -Polylysine Addition on Pullulan Biodegradable Films for Blueberry Surface Coating

A biodegradable film was successfully prepared using pullulan and epsilon-polylysine (epsilon-PL). The impact of epsilon-PL contents on biodegradable film was explored through mechanical properties, water vapor permeability, and an FTIR spectroscopy test. Amongst all the prepared films, the 0.5% epsilon-PL had the most desirable results in film performance. The TS, EAB, and WVP values were 5.63 MPa, 21.5%, and 0.27 x 10-6 g m/Pa h m2, respectively. The blueberries coated with 0.5% epsilon-PL and pullulan were stored at 20 degrees C for 12 days. The effect of edible coatings on the performance of blueberries was evaluated by detecting the physicochemical properties and the contents of antioxidants. The experimental results displayed that epsilon-PL and a pullulan blend film could decrease the weight loss and maintain the hardness, polyphenol, anthocyanin, and antioxidant capacity of the blueberry preservation. The results indicated that the biodegradable film is a potential fruit-coating material.