Effect of Biocomposite Edible Coatings Based on Pea Starch and Guar Gum on Nutritional Quality of Valencia Orange During Storage

The application of environmentally friendly components is an approach for substitution of synthetic substances in commercial waxes applied to citrus. In this study, the effect of biocomposite edible coatings based on pea starch and guar gum (PSGG) on total vitamin C, phenolic, flavonoid, anthocyanins, and carotenoid content, and antioxidant capacity of Valencia orange stored at 5 and 20 degrees C for 4 weeks are evaluated. The fruits are coated by a single layer PSGG coating, blended composite PSGG coating containing shellac (Sh) and oleic acid (OA) as hydrophobic compounds (PSGG-Sh), and a layer-by-layer (LBL) coating (PSGG as an internal layer and Sh as an external layer). The results show no significant differences in changes of bioactive compounds between coating treatments after first week storage at both temperatures. The PSGG coatings incorporated with hydrophobic compounds (PSGG-Sh) better preserves the nutritional value and the antioxidant potential of oranges during storage compared with other treatments. The single layer PSGG coating is almost similar to bilayer coating in preserving nutritional value of fruit during storage and less effective than the blended composite PSGG-Sh coating.