Comparative effects of pomegranate peel extract dipping and CMC coating on postharvest shelf-life and quality of strawberries

Abstract

Bioactive compounds in pomegranate peels are promising natural preservatives, and edible biopolymer coatings can reduce postharvest losses in highly perishable fruits. Here, we compared aqueous pomegranate peel extract (PPE) dipping (1.5, 2.0, 2.5, and 3.0% w/v) with a composite coating of 1.0% (w/v) carboxymethyl cellulose (CMC) enriched with PPE at the same concentrations for strawberry preservation. Strawberries were stored at 4 ± 1 °C for 10 days and evaluated for physicochemical quality, antioxidant capacity, and microbiological status. Weight loss increased in all treatments but was significantly minimized (p < 0.05) by CMC + PPE (3.0%), reaching 4.40% at day 10 versus 11.01% in PPE-only (1.5% (w/v)) fruit (≈ 60.0% lower). Decay was delayed by the composite coating, with the lowest incidence at day 10 for CMC + PPE (3.0%) (28.7%). DPPH radical scavenging activity peaked around day 5 and remained higher in coated samples; CMC + PPE (3.0%) retained 75.32% activity at day 10. Microbial spoilage was reduced, and CMC + PPE (3.0%) showed the lowest mold and yeast count (3.52 Log CFU/g). Overall, embedding PPE in a CMC matrix provides a biodegradable approach to extend strawberry shelf life during cold storage. CMC–PPE coatings reduced weight loss and delayed strawberry decay. CMC + 3% (w/v) PPE gave the lowest weight loss after 10 days at 4 °C. Composite coating maintained higher antioxidant activity during storage. CMC + 3% (w/v) PPE lowered mold and yeast counts versus other treatments. This approach supports cold-chain handling for strawberry distribution.