Chitosan films incorporating litchi peel extract and titanium dioxide nanoparticles and their application as coatings on watercored apples

Nano-titanium dioxide (nano-TiO2) and litchi peel extract (LPE) were added to chitosan (CS) matrix to develop a novel active packaging film and watercored apple coating. The addition of nano-TiO2 and/or LPE enhanced mechanical strength, water vapor barrier properties, and thermal stability of CS-based films. The total phenolic content and antioxidant capacity of the films were enhanced by LPE incorporation. Viscosity and wettability of the coating solutions and their impact on the storage quality of watercored Fuji apples at 0 ± 1℃ for 180 d were investigated. Coating treatment significantly inhibited respiration rate, weight loss, and softening. Polyphenol oxidase activity, electrolyte leakage and malondialdehyde accumulation were inhibited by coating treatment. A CS + TiO2+LPE coating was the most effective treatment for maintaining cold storage quality of watercored apples. This combination presents promising applications as an active food packaging film and fruit preservation coating.