Innovative edible films for food preservation: Combining pectin and flavonoids from citrus peels with soy protein isolates

In this study, sequential extraction technology was employed to extract pectin and flavonoids from citrus peel by-products. Subsequently, citrus flavonoids (CF) were incorporated into a matrix comprising soy protein isolate (SPI) and citrus pectin (CP), resulting in the development of a series of active films (SPI/CP-CFs). The physicochemical properties of these films were evaluated along with their capability in food preservation. The SPI/CP-CFs films exhibited exceptional mechanical properties, thermal stability, and gas barrier properties. Furthermore, the films exhibited enhanced antioxidant and antimicrobial activities due to the sustainable release of CF. In practical applications, these antimicrobial edible films were more effective in extending the shelf life and maintaining freshness of red grapes and pork compared to CF-free counterparts. These findings suggest that the novel edible films based on the formulation of SPI, CP, and CF hold significant potential as versatile active packaging materials for preserving both fruit and meat products.