One aspect of the disclosure herein contemplates a composite film comprising lysozyme incorporated within a chitosan polymer matrix. In another aspect, there is disclosed a film that includes chitosan, and about 10 to about 200 weight percent lysozyme, based on the weight of the chitosan. Also disclosed is a method for making a film that includes dissolving or dispersing chitosan and lysozyme in an aqueous medium resulting in a film-forming solution or dispersion; applying the film-forming solution or dispersion to a substrate surface; and converting the film-forming solution or dispersion into a film. In a particularly useful application, the film is an antimicrobial protectant for a food article.