Application of Intelligent Sodium Alginate/Polyvinyl Alcohol Film with UV-Catalyzed Nano-Titanium Dioxide to Enhance Anthocyanin Cross-Linking in Salmon Freshness Monitoring

Abstract

In this study, novel bionanocomposites consisting of purple asparagus anthocyanin and photocatalyzed titanium dioxide (TiO2) nanoparticles in a sodium alginate/polyvinyl alcohol matrix are prepared using a hybrid method. The film is applied to the detection of freshness and flavor substances in salmon. The water content and water vapor permeability of the composite films ware significantly reduced by the addition of anthocyanins and nano TiO2. Scanning electron and atomic force microscopy images showed that the addition of anthocyanins and nano-TiO2 generates rough and porous film surfaces. The UV-treated polymer (UV-SPTA) films exhibited enhanced mechanical strength, antimicrobial and antioxidant properties, as well as high sensitivity and rapid response to alkalinity compared to other treatment groups. In addition, the UV-SPTA film enhanced the freshness of salmon stored under refrigeration for 84 h by significantly inhibiting microbial growth and spoilage of flavor substances, with a more pronounced color change than in the other treatment groups.

Keywords: Anthocyanins, Sodium alginate, Titanium oxide nanoparticles, Intelligent and antifungal film