The Effect of Edible Coating Applications on Fruit Quality, Antioxidant Activity, Phenolic and Anthocyanin Content and Shelf Life of Sour Cherry (Prunus cerasus L.) Fruits

Sour cherry is a highly perishable non-climacteric fruit characterized by rapid postharvest quality deterioration. In this study, a novel biodegradable edible coating system based on chitosan microparticles (CsMPs), green-synthesized selenium microparticles (SeMPs), and thyme essential oil was developed to enhance the postharvest quality and extend the shelf life of sour cherry fruits. The results demonstrated that all coating treatments significantly reduced postharvest quality losses compared to the control. The CsMPs + Oil treatment was most effective in minimizing weight loss (9.44% vs. 13.54% in control at 21 °C) and preserving color parameters, attributed to its barrier properties preventing moisture loss. The incorporation of selenium microparticles markedly enhanced antimicrobial activity, with CsMPs + SeMPs reducing decay rates to 19.5%, compared to 50% in the control, at 21 °C. Additionally, CsMPs + SeMPs effectively suppressed the respiration rate and maintained fruit firmness, indicating delayed metabolic activity. Biochemical analyses revealed that the coatings moderated the increase in total soluble solids, total phenolic content, and total anthocyanin accumulation, while CsMPs + SeMPs was superior in slowing the decline in antioxidant activity. Among treatments, CsMPs + SeMPs and CsMPs + SeMPs + Oil emerged as the most effective formulations. This study highlights the potential of multifunctional edible colloidal coatings as sustainable and eco-friendly alternatives to conventional packaging for extending the shelf life of highly perishable fruits.