Postharvest Eucalyptus Leaf Extract Application Extends the Sustainable Supply of Strawberries by Retaining Physicochemical Quality during Cold Storage

Strawberry is a delicate fruit with a short shelf life after harvest. High metabolic activities and fungal decay deteriorate its quality. In an attempt to extend its shelf life and maintain its quality while retaining its antioxidant potential, the harvested fruits of strawberry cv. Chandler were dipped in 30% eucalyptus leaf extract (ELE). Weight loss, fungal decay index, percentage of decayed fruits, respiration rate, and electrolyte leakage were all reduced in ELE-treated strawberries. The enzymatic activities of catalase in fruits increased initially until the fifth day of storage but then started to decline during the later period while superoxide dismutase and peroxidase activities continued to rise until the 10th day and then declined. With higher contents of total phenolics, ascorbic acid, total antioxidants, and anthocyanin, the application of ELE maintained the general acceptance, firmness, flavor, and marketable fruit percentage. Titrable acidity (TA) and sugar–acid ratio (SAR) were also significantly affected by ELE application. A declining trend was observed in TA during storage, along with an increase in SAR. The pH and soluble solid contents of strawberry juice were not significantly changed by the application of ELE; however, both attribute scores were greater than those for the control. In conclusion, ELE could be used as an environmentally safe method to postpone senescence and maintain postharvest quality for up to 15 days.