Abstract: Protein-based film has an important role in the field of edible film due to its characteristics of non-toxicity, biodegradability, green environmental protection, shelf life extension of foods, and nutrient supply. How to improve its relatively weak mechanical strength and insufficient barrier performance has always been and will be a problem of great concern for researchers. This article first reviews the formation mechanism and properties of protein-based film with emphasis on the existing technologies for the improvement of protein-based film properties based on molecular cross-linking including physical cross-linking, chemical cross-linking, enzymatic cross-linking and physical energy-induced cross-linking. Finally, the significance and development trend of cross-linking in protein-based film are also proposed.

Key words: edible film, protein-based film, molecular cross-linking, performance improvement