Titanium dioxide nanoparticles and elderberry extract incorporated starch based polyvinyl alcohol films as active and intelligent food packaging wraps

Polyvinyl alcohol (P)/starch (S), titanium dioxide nanoparticles (TiO2)/elderberry extract based bionanocomposites (PSTE) were developed by solvent casting method. The developed films were analyzed for morphological, functional, water barrier, mechanical, antimicrobial, food packaging as well as biodegradability studies. Results of the study showed that tensile strength, moisture barrier and antimicrobial properties of the films were significantly improved by the addition of TiO2 nanoparticles. TiO2 nanoparticles were found to be homogeneously dispersed in the polymeric matrix and had good compatibility enabling better functional properties. The elderberry extract addition caused the nanocomposite film a potential pH sensor. Further, the cherry tomato coated with PSTE solution showed reduced weight loss and did not have any sign of microbial infection up to 22 days. Biodegradation studies by soil burial test proved the biodegradability of PSTE bionanocomposites and hence have great promise as active and intelligent food packaging materials.