Efficacy of an antifungal edible coating for the quality maintenance of Tarocco orange fruit during cold storage

This study evaluated the effectiveness of a novel pectin-based edible coating (PBEC), alone or added with the antagonistic yeast Wickerhamomyces anomalus BS91 (PBECY), in reducing postharvest rots of Tarocco orange fruit. Their antifungal efficacy was assessed in vitro and in vivo, as well as their ability to preserve fruit quality under refrigerated conditions on three different cultivars, comparing a commercial wax amended with a fungicide. For all the treatments, the decay incidence, physiological disorders, weight loss and physical-chemical parameters were evaluated. The in vivo tests results indicated that PBECY enhanced the antifungal effect compared to PBEC, given the significant reduction (p ≤ 0.01) of Penicillium digitatum (PD) decay incidence (up to 90%). After 30 d of cold storage, both PBEC and PBECY reduced fruit decay (p≤ 0.05) in all cultivars, with values between 0 and 1.2%, relatively to the untreated control (up to 10%). Pectin-coated fruit showed a cultivar-dependent weight loss, with values comparable or higher to the other treatments, respectively for T. Lempso and T. Messina, whereas weigh loss in T. Sciara was higher only when coated with PBEC. Fruit physical and chemical parameters were preserved until 30 d of storage, thus demonstrating the potential of this edible coating for future industrial application.