Hydrophobic, oil‐repellent, and antimicrobial guar gum‐chitosan composite paper coating for sustainable food packaging

Abstract Challenges in sustainable food packaging include ensuring effective moisture and oil barriers, antimicrobial protection, and developing cost‐effective, scalable production methods. This study introduces a hydrophobic, oil‐repelling, antimicrobial coating of a guar gum (GG)‐chitosan (CS) blend applied via a dip coating approach on blotting paper. By incorporating sodium tri‐polyphosphate (STPP) as a cross‐linker, the optimized formulation (1.5% guar gum, 0.09% STPP, 1% chitosan, and 1.5% glycerol) achieved notable hydrophobicity with a water contact angle of 136.1 ± 2.2°. This study is significant as it offers a sustainable, eco‐friendly food packaging solution with enhanced hydrophobic, oil‐repellent, and antimicrobial properties.