Development of edible seaweed-based coating for postharvest preservation of mangoes

Abstract

The post-harvest loss of approximately 28 % of mangoes in Brazil significantly contributes to global food waste, while millions face chronic hunger. It is essential to develop sustainable and low-cost solutions to reduce these losses, ensuring quality and food safety for end consumers. This study evaluated the efficacy of a sodium alginate biopolymer and aqueous extract of Padina pavonica seaweed-based active edible coating to preserve Tommy Atkins mangoes stored at 10 °C for 20 days. The P. pavonica extract showed high phenolic (736.17 mg GAE/g) and flavonoid (27.40 mg QE/g) content, with strong antioxidant activity (98.20 % DPPH reduction at 1000 μg mL⁻¹), and effectively inhibited bacterial and fungal growth, including Staphylococcus aureus, Escherichia coli, Alternaria, and Colletotrichum. Mangoes treated with the coating demonstrated improved quality and delayed ripening, evidenced by (i) clearer pulp, (ii) greater firmness suitable for commercialization, (iii) 3.27 % mass loss indicating delayed ripening, and (iv) absence of fungal diseases. These results highlight the coating's potential to extend shelf life and maintain mango quality during post-harvest storage. In addition, a technical-economic analysis revealed the coating's economic viability, offering cost savings exceeding 30 %, potentially reaching 50 %, compared to carnauba wax.