Haonan Guo  ,  Yijing Li ,  Xinxin Cheng ,  Quanbin Fu ,  Jin Wang  ,  Bowen Zhang  ,  Shikai Zhang  , Houshen Li 

Abstract 

Pectin films show promise as biodegradable packaging for fruit preservation. However, they suffer from limitations including brittleness, lack of antimicrobial activity, and poor processability. Herein, tannins were extracted from bayberry bark and self-assembled with kraft lignin into lignin–bayberry bark tannin (LBBT) nanoparticles (NPs) through π–π stacking and hydrogen bonding interactions. The prepared LBBT NPs were employed to comprehensively reinforce a pectin film. LBBT NPs are highly compatible with pectin, dispersing evenly in the pectin matrix and filling the interstitial spaces between molecular chains through hydrogen bonding to promote intermolecular and intramolecular crosslinking and entanglement. LBBT NPs significantly improved the physical properties of the pectin films, including mechanical strength (51.04 MPa), water contact angle (81.40°), water vapor permeability (0.97 × 10−12 g/cm·s·Pa), oxygen permeability (1.37 × 10−15 cm3(STP)·cm/(cm2·s·Pa)), with reinforced ultraviolet resistance, antioxidant activity, and thermodynamic stability. Furthermore, the pectin–LBBT NP film demonstrated significant inhibitory effects against Staphylococcus aureus (97.86% inhibition), Escherichia coli (95.10% inhibition), and Botrytis cinerea (51.61% inhibition). The films are proven to be biosafe and can significantly extend the storage life of both climacteric and non-climacteric fruits while maintaining their postharvest quality. Remarkably, water can act as a switch for molecular breakage and rearrangement, enabling the film to be molded into diverse complex two- and three-dimensional configurations with compelling plasticity. This strategy addresses critical limitations in existing pectin films and pioneers new opportunities for developing high-performance, multifunctional pectin-based active packaging.

Paper Linkage:https://www.sciencedirect.com/science/article/pii/S0268005X26002602