Enhancing postharvest quality and storability of bananas using UV-blocking and antioxidant bionanocomposite coatings enriched with nettle seed essential oil nanoemulsion

Abstract

Biodegradable active packaging systems are emerging as sustainable alternatives to conventional plastics for extending food shelf life. Essential oil-based nanoemulsions are effective active components for the development of functional films and coatings. In this study, a novel biopolymer-based nanocomposite film was developed by incorporating nettle seed essential oil nanoemulsions (NEs) into pea protein and fenugreek seed mucilage matrix to enhance UV-blocking, antioxidant, and food preservation properties. NEs prepared with 2–4% nettle essential oil exhibited high stability (-28.90 to -37.07 mV) and nanoscale particle size (146–189 nm). Increasing NE concentration (0–20%, NF0–NF20) significantly influenced film properties, enhancing matrix interactions and structural complexity as confirmed by SEM and FTIR analyses. NE incorporation increased film thickness, while density, water vapor permeability, and solubility remained within a stable range. Oxygen permeability increased at NF10 and NF15, while NF0 and NF20 showed similar and lower values. All films showed strong UV-blocking ability with reduced visible light transmission. Mechanical properties were modulated, with decreased tensile strength (2.30–1.76 MPa) and increased elongation at break (up to 91%), indicating enhanced flexibility. In addition, total phenolic content and antioxidant capacity increased with higher NE concentration, demonstrating improved bioactive functionality. Pea protein and fenugreek seed mucilage-based nanocomposite coatings effectively delayed banana softening and maintained firmness, with NF20 showing improved control of peel color changes. Overall, the NE-incorporated films demonstrated potential for active and sustainable food packaging applications by integrating UV protection, antioxidant activity, and improved functional performance.