A multifunctional chitosan-derived conformal coating for the preservation of passion fruit

A third of all fruits are wasted at the agricultural and postharvest stages before reaching the consumer. This spoilage issue is particularly common for respiratory climactic fruit such as Passion fruit, as it possesses a very short shelf life due to dehydration and microbial growth, greatly limiting its storage, transportation and marketing. In order to solve the problem of fruit spoilage, this work developed a multifunctional biomass-derived conformal coating from quaternary ammonium based water-soluble chitosan (WSC) and tannic acid (TA). The coating material has excellent transparency, toughness, UV resistance, antibacterial ability, oxidation resistance and washability. The experiment showed that the coated passion fruit exhibited an apparent retardation effect in weight loss, shrinkage index, and firmness, prolonging the shelf life 7 days longer. These results suggest that the WSC/TA composite coating could effectively prevent oxygen oxidation and water loss, and delay fruit ripening, showing good potential in fruit preservation, especially in the preservation quality and economic benefits of passion fruit.