Development and evaluation of gum arabic-based antioxidant nanocomposite films incorporated with cellulose nanocrystals and fruit peel extracts

The active food packaging films prepared in this study used gum arabic (GA)-cellulose nanocrystals (CNC) as the film-forming matrix, and grape skin extract (GSE), pomegranate peel extract (PPE) and red pitaya peel extract (RPPE) as natural antioxidants by solution casting method. The combination of extracts changed the color and microstructure of the films, resulting in a decrease in mechanical strength and water resistance, but their flexibility and light transmittance were improved. Particularly, the PPE film can almost completely block the passage of ultraviolet light (200-400 nm). In addition, the composite films carrying the extracts possessed antioxidant capacity, which can extend the storage period of raspberries. The PPE film with the highest activity prominently reduced total color difference (4.08-2.08), weight loss rate (19.71-5.81%), moisture evaporation (21.29-18.22%) and fluctuation of nutrient content of the fruits in the raspberry preservation test.