Effect of Pullulan-Chitosan Film Containing Titanium Dioxide (TiO2) Nanoparticle and Tarragon Essential Oil on the Quality Properties During Refrigerated Storage of Rainbow Trout Fillets

Nowadays, there is a serious ecological problem with synthetic plastics in seafood packaging because of their total non-biodegradability. The objective of this study is the estimation of the influence of pullulan (P)-chitosan (CH) film in combination with titanium dioxide nanoparticles (TiO₂ NPs) and tarragon essential oil (TEO) on the bacterial counts, physicochemical properties, and sensory analysis of rainbow trout fillets during refrigerated storage. For this aim, the treated fillets were divided into: pullulan-chitosan (PCH), PCH-TiO₂, PCH-TEO, and PCH/TiO₂-TEO. The results demonstrate that the combination of TiO₂ and TEO with PCH solution is an active nanocomposite film with antimicrobial and antioxidant effects. The wrapped fillets improved the physicochemical properties (such as total volatile bases- nitrogen [TVB-N], pH, peroxide value [POV], and thiobarbituric acid [TBA]) during refrigeration storage. The highest rate of TVB-N (30.33 mg/N100 g), pH (7.04), POV (1.79 meq peroxide/1000 g lipid), and TBA (3.07 mg MDA/kg) was recorded in PCH/TiO₂-TEO wrapped fillets on day 12. The PCH-TEO was better than the (PCH-TiO₂) groups in reducing the rate of oxidation of lipids of rainbow trout fillets. However, there was no significant difference between them in the control of the microbial population. The sensory acceptance score in rainbow trout fillets wrapped with PCH/TiO₂-TEO was better than other samples on day 12 (3.66), and it was lower than the critical score for fishery products. Overall, these findings suggest that TiO₂/TEO PCH-based nanocomposite film could be utilized as an alternative packaging method in seafood products with notable antioxidant, antibacterial, and nutritional properties.