Preparation and characterization of k-carrageenan/konjac glucomannan/TiO2 nanocomposite film with efficient anti-fungal activity and its application in strawberry preservation.

A nano-composite film was prepared from k-carrageenan (KC), konjac glucomannan (KGM) and TiO2 nanoparticles (NPs) by solvent casting method. The morphology and structure of the KC/KGM based nano-composite films prepared from different weight ratio of TiO2 NPs were characterized by SEM, XRD and FT-IR techniques. The addition of TiO2 NPs to KC/KGM films improved the mechanical, thermal, structural, and barrier properties of nano-composite films. In particular, the film containing 7 wt% of TiO2 NPs exhibited effective photocatalytic anti-fungal activity (79%) for Penicillium viridicatum after irradiating 6 h through generating reactive oxygen species thus destroying the fungi. Benefitting from the improved characteristics investigated above, the nano-composite films showed a favorable effect on strawberry storage. Overall, the fabricated KC/KGM/TiO2 nano-composite films have a broad application in the field of food preservation and packaging applications.