Ag-chitosan nanocomposites in edible coatings affect the quality of fresh-cut melon

Abstract

The effect of incorporating Ag-chitosan nanocomposites into chitosan coatings on the quality of fresh-cut melon over 13 d at 5 °C has been studied. The respiration rate of fresh-cut melon was reduced after coating treatments. Particularly, the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites) showed lower RR increments during storage compared to that of the rest of coatings. Coated samples reached a steady-state atmosphere within packages of 12.6–16.2 kPa of CO2/2.3–3.7 kPa of O2 after 9–10 d. Softening was prevented in advanced storage periods by the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites). The colour, soluble solids content, sucrose, glucose and fructose, pH, TA, and citric and malic acids were not greatly affected by the coating treatments. Furthermore, the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites) showed the highest total vitamin C content after 13 d at 5 °C compared to the rest of the coating treatments. The coated samples were better sensory-scored than were the uncoated samples. Particularly, the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites) showed lower translucency, which is the most important visual alteration in fresh-cut melon. Only the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites) induced a microbicidal reduction (0.6 log units) from days 10 to 13. We conclude that the coating with red claw crayfish-extracted chitosan (including red claw crayfish-extracted Ag-chitosan nanocomposites) has the potential to be applied in the fresh-cut industry to extend the shelf-life of these products.