High-performance carrageenan/carboxymethyl cellulose films using quercetin-functionalized polyphenol-based metal-organic frameworks for fruit packaging.

Abstract

A multifunctional active packaging film was developed by incorporating quercetin-functionalized gallic acid‑zinc metal-organic frameworks (QC@GZ-MOF) into a carrageenan/carboxymethyl cellulose (CG/CMC) binary matrix. The polyphenolic structure of quercetin, particularly its catechol moiety, acted as an effective crosslinking component, enhancing the interactions between the GZ-MOF and the CG/CMC matrix. This promoted the formation of a continuous and dense hybrid network with enhanced interfacial cohesion and structural stability. Therefore, compared with the neat CG/CMC film, the CG/CMC/QC@GZ-MOF film exhibited a 47.4% increase in tensile strength and significant reductions in water vapor permeability and oxygen transmission, demonstrating improved mechanical strength and barrier performance. Besides, the water contact angle increased to 90.5°, demonstrating improved surface hydrophobicity. The fabricated composite film exhibited strong active functions, such as ABTS radical scavenging and UV-blocking, as well as distinct antibacterial activity against E. coli and L. monocytogenes. In a blueberry preservation test, this film effectively reduced weight loss and inhibited microbial proliferation, maintaining fruit quality for 18 days. These findings suggest that catechol-derivative functionalization is an effective strategy for fabricating sustainable high-performance packaging materials with strong potential to enhance food safety and extend shelf life.