Abstract:Food packaging plays a key role in maintaining food quality and extending shelf life. However, the traditional plastic packaging has environmental pollution and sustainability problems, so seeking sustainable and environmentally friendly alternative materials has become a hot spot of current research. Compared with single-layer bio-based films, multi-layer bio-based films show better mechanical properties, barrier properties, etc. Since the multi-layer packaging materials have a more complex internal structure and larger interlayer spaces between the layers (which makes them more suitable for the introduction of active substances), these materials have attracted extensive attention and research in recent years. In this paper, the construction methods of multilayer bio-based films and their applications in the field of packaged foods are reviewed. The classification of biobased packaging materials is discussed, and the preparation methods of multi-layer biobased films, including layer self-assembly technology (LbL), electrodynamic method, co-extrusion method and solvent casting method, as well as their advantages and disadvantages are introduced. The recent research progress of multi-layer biobased packaging in the field of food are comprehensively analyzed and summarized. The future research direction and development trend of bio-based multilayer films are proposed.
