Indicative bacterial cellulose films incorporated with curcumin-embedded Pickering emulsions: Preparation, antibacterial performance, and mechanism

Biodegradable, sustainable, and multifunctional intelligent food packaging has attracted extensive attention due to the concerns about the environmental pollution, the health hazard, and the food safety of plastic packaging. Herein, a multifunctional bacterial cellulose (BC)-based film (termed BC-PE-Cur) was fabricated for intelligent food packaging. The film was simply prepared by vacuum filtration and compression of a mixture of the BC and the curcumin (Cur)-embedded Pickering emulsion (PE) stabilized with the natural protein-polysaccharide hybrid nanoparticles (PPH NPs). The Pickering emulsion droplets containing Cur were uniformly distributed within the film and adhered to the film surface, resulting in a uniform dispersion of Cur in the film, and a thicker, rougher film with a laminated pore structure. The BC-PE-Cur film showed excellent antibacterial, antioxidant, UV-shielding, water vapor barrier, and mechanical properties. BC-PE-Cur film can extend the shelf life of basa fish by delaying the lipid peroxidation and inhibiting the growth of spoilage microorganisms. Moreover, during the storage of basa fish, BC-PE-Cur films underwent significant color change due to the production of alkaline substances, which could indicate the freshness of basa fish. This study provides an attractive strategy to construct multifunctional smart bio-based composite films containing non-water-soluble active ingredients for food packaging and freshness monitoring.