Active Films Based on Orange Peel Pomace Soluble Dietary Fiber and Sodium Alginate Reinforced by Dual-Functional Cellulose Nanocrystal/Zinc Oxide Hybrids for Antibacterial Food Packaging

In this study, dual-functional cellulose nanocrystal/zinc oxide hybrids (ONCC@ZnONP) were constructed from navel orange peel pomace. The incorporation of these hybrids systematically improved the overall properties of OSDF-based antibacterial active packaging films. A series of antibacterial active packaging films (O/CZ) were successfully prepared using OSDF as the matrix and ONCC@ZnONP as the active filler. The effects of different ONCC@ZnONP loadings on the microstructure, physical properties, and antibacterial properties of the films were systematically analyzed. The results showed that ONCC@ZnONP was uniformly dispersed within the OSDF matrix, exhibiting favorable interfacial compatibility. The incorporation of ONCC@ZnONP significantly enhanced the tensile strength, UV-shielding property, and antibacterial activity of the O/CZ films. In the blueberry preservation application, the decay rate of the O/CZ films decreased with increasing ZnO loading. Based on the comprehensive balance of antibacterial preservation and physical quality maintenance, the O/CZ8 film (8 wt% ONCC@ZnONP) showed the optimal preservation performance. Specifically, it showed a weight loss of 9.67%, maintained a firmness of 9.07 N, and achieved a decay rate reduction of 78.74% compared to the OSDF/SA film. These results showed that the developed antibacterial active packaging films hold great potential for food packaging and preservation applications.