Active edible films with plant extracts: a updated review of their types, preparations, reinforcing properties, and applications in muscle foods packaging and preservation.

Currently, edible films have been increasingly explored to solve muscle food spoilage during storage, especially through the incorporation of plant extracts to develop edible packaging materials. Natural polymers matrices with plant extracts are befitting for fabricating edible films by casting methods. In the films system, the structure and physicochemical properties were strengthened via chemical interactions between active molecules in plant extracts and the reactive groups in the polymer chain. The antibacterial and antioxidant properties were dramatically reinforced through both physical and chemical actions of the plant extracts. Additionally, edible films imbedded with color-rich plant extracts could be considered as potential sensitive indicators to monitor the spoilage degree of muscle foods in response to change in gas or temperature. Furthermore, these films could increase sensory acceptability, improve quality and prolong the shelf life of muscle foods. In this article, the types, preparation methods and reinforcing properties of the edible films with plant extracts were discussed. Also, the applications of these films were summarized on quality maintenance and shelf-life extension and intelligent monitoring in muscle foods. Finally, a novel technology for film preparation achieving high-stability and sustained release of active compounds will become an underlying trend for application in muscle food packaging.