Postharvest Quality Retention of Citrus limon L. cv. Kagzi Lemon Under Cold Storage Using Chitosan and Aloe Vera Gel Coatings

Lemon ( Citrus limon L.) is a widely cultivated citrus fruit valued for its nutritional and medicinal properties; however, it is highly perishable and prone to postharvest losses. This study aimed to evaluate the efficacy of natural edible coatings, chitosan (CS) and aloe vera gel (AV gel), applied individually and in combination, in preserving the postharvest quality of lemon fruits during 60 days of cold storage at 4 °C and 85% relative humidity. Nine treatments were tested, including a control, two concentrations of CS (2% and 3%), two concentrations of AV (10% and 15%), and four combinations of CS and AV gel. Various quality parameters were monitored at 0-, 10-, 20-, 30-, 40-, 50-, and 60-day intervals, including weight loss, fruit decay, juice content, firmness, total soluble solids (TSS), titratable acidity (TA), total sugars (TS), reducing sugars (RS), non-reducing sugars (NRS), total phenolic content (TPC), total antioxidant capacity (TAC), and antioxidant enzyme activities (catalase, peroxidase and superoxide dismutase) were monitored at 10-day intervals. The results demonstrated that the combined coating of 2% CS and 10% AV was the most effective in minimizing weight loss (34.25%) and decay incidence (9.22%) at day 60, while maintaining biochemical quality, including higher vitamin C content, phenolic content, and antioxidant activity. This research highlights the potential of CS and AV gel-based coatings as eco-friendly alternatives to synthetic preservatives for extending shelf life.