Impact of cellulose nanocrystals and coleus aromaticus essential oil on the permeability of polylactic acid/chitosan films for fruit packaging application

Abstract Biopolymer films are increasingly used in sustainable fruit packaging; however, their practical application is often limited by poor gas and water vapor barrier properties. Enhancing these barrier functions is critical to minimizing moisture loss, oxidative spoilage, and quality degradation in packaged fruits. This study investigates the effects of incorporating cellulose nanocrystals (CNCs) and Coleus aromaticus essential oil (CAEO) on the gas and water vapor permeability of polylactic acid (PLA)/chitosan (CHI) composite films. Films containing higher CNC concentrations (3–4 wt%) exhibited increased porosity and surface defects, which significantly elevated oxygen, carbon dioxide, and water vapor transmission rates (WVTR). In contrast, the addition of CAEO reduced gas permeability and WVTR, likely due to its hydrophobic nature and matrix-densifying effects. The films were further evaluated for their effectiveness in preserving mango fruit quality during storage. While soluble solid content (SSC) showed no significant differences across treatments ( P > 0.05), fruit treated with 1.2% CAEO films exhibited significantly lower weight loss ( P < 0.05) compared to untreated controls. The combination of CNCs and CAEO enhanced the functional performance of PLA/CHI films, indicating their potential as biodegradable active packaging for postharvest fruit preservation, though validation under realistic storage and export conditions is still required.