Combination effects of calcium chloride and nano-chitosan on the postharvest quality of strawberry (Fragaria x ananassa Duch.)

This study aimed to investigate influences of calcium chloride (CaCl2) concentrations combined with nanochitosan coating on the quality of strawberry during postharvest storage. The fruit were dipped in different concentrations of calcium chloride (1 %, 2 %, 3 %, 4 %) before being coated with 0.2 % nano-chitosan. Physicochemical analysis including the overall quality index, weight loss, firmness, titratable acidity, total soluble solid, c-ascorbic acid content, antioxidant capacity, total phenolic content, total anthocyanin content, and malondialdehyde content were performed in 3 d intervals until fruit became unmarketable. Among six examined treatments, a combination of 3 % CaCl2 and nano-chitosan (NCTS) was the most effective one as maintaining the highest score of overall quality index of strawberry stored at 4 degrees C up to 15 d. The treatment also significantly reduced weight loss, preserved c-ascorbic acid, total anthocyanin contents, antioxidant capacity, and retarded malondialdehyde production. The scanning electron microscope image showed a smooth surface of strawberries coated with 3 % CaCl2 combined 0.2 % nano-chitosan. There has no bitterness detected in the treated strawberries after being stored 15 d at 4 degrees C. The major volatile compounds determined in the initial day were remained until the 15th d of storage.