Cellulose nanocrystals and zinc oxide in pineapple starch films for enhanced banana shelf-life

Abstract

This study investigates the development of biodegradable films from pineapple stem starch enhanced with cellulose nanocrystals (CNC) and zinc oxide (ZnO) nanoparticles for improved food preservation. The film-forming behavior of pineapple stem starch was examined with varying concentrations of glycerol (0-30%), CNC (0-1.5%), and ZnO (0-20%). Rheological measurements showed that glycerol concentrations significantly influenced the viscoelastic properties of the starch solutions, with a notable peak in viscosity observed at 20% glycerol. The addition of CNC increased the storage modulus (G’) and viscosity of the starch solutions, indicating enhanced structural integrity. ZnO nanoparticles imparted effective UV-blocking capabilities to the films, with optimal performance observed at 10% concentration. Water vapor permeability (WVP) of the films slightly increased with ZnO content, ranging from 0.0127 to 0.0157 g·m⁻¹·h⁻¹·Pa⁻¹. Scanning electron microscopy (SEM) analysis showed uniform dispersion of ZnO nanoparticles within the starch matrix. The ZnO-enhanced starch coatings effectively extended the shelf life of bananas by delaying the ripening process. This study demonstrates the potential of pineapple stem starch-based films enhanced with CNC and ZnO as a sustainable and effective solution for food packaging, contributing to reduced food waste and environmental impact.