Impact of Polyphenols on Water Vapor Barrier in Carboxymethyl Cellulose Films Reinforced with Bacterial Cellulose Nanofibers

Abstract Polysaccharide-based films can preserve food and reduce food loss and waste. Nonetheless, the relatively high water vapor permeability (WVP) constrains their wider implementation. While various methods can enhance polysaccharide-based films’ water barrier, the embedment of polyphenols has been reported as a promising strategy to decrease WVP. This study investigates the effect of various classes of polyphenol on a carboxymethyl cellulose (CMC) film reinforced with bacterial cellulose nanofibers (BCNF), primarily on the film’s water barrier properties, to allow broader applications and expand the optimization of polysaccharide-based films with enhanced water barrier. The addition of polyphenols to the CMC/BCNF matrix reduced the WVP by about 17–25% and enhanced mechanical strength by about 77–123%, depending on the polyphenol class, and exhibited antioxidant and contact-based antimicrobial activity. Remarkably, the incorporation of catechin or curcumin resulted in films with notably improved characteristics, owing to their chemical structure and hydrophobicity, respectively. Among the evaluated polyphenols, it was implied that the incorporation of single polyphenol compounds with two phenyl rings into a CMC/BCNF film matrix resulted in enhanced properties. This study developed an understanding of the relationship between the characteristics of a polyphenol compound and its interaction and effect in a CMC/BCNF film matrix. The knowledge provides a basis for embedding polyphenols in polysaccharide films to improve their overall properties.