Carbon dots-based reinforced hydrogen-rich water nanocomposite coating for storage quality of fresh-cut pear

Designing environmentally friendly edible nanocomposite films with antioxidant functions is of great interest in the field of fresh-cut fruits. Herein, Pleurotus eryngii carbon quantum dots (PER-CDs) were prepared from Pleurotus eryngii by-products, successfully characterized and added to chitosan (CS)/hydrogen-rich water solution to develop CDs/CS nanocomposite films (CS/PER-CDs), which was successfully applied to the preservation of fresh-cut pears. Thereinto, the fresh-cut pears treated with CS/2%PER-CDs nanocomposite films had minimum weight loss of 3.38% and the best retention of moisture, color, soluble solids and titratable acids after 5 days of storage. Importantly, the fresh-cut pears in the CS/2%PER-CDs treatment group had the lowest relative conductivity (37.53%) and MDA content of 1.94 μmol/kg, which could indicate that the CS/2%PER-CDs nanocomposite films maintained good cell membrane integrity of fresh-cut pears. In addition, the CS/2%PER-CDs treatment group effectively reduced the maximum respiration intensity (51.67 mgCO2/Kg·h) and ethylene production rate (0.75 μg/kg·h) of fresh-cut pear. Therefore, PER-CDs can be added into chitosan-based coating film as a functional component to make nanocomposite films and applied in fresh-cut fruits preservation effectively.