Water-resistance chitosan film through enzymatic treatment and layer-by-layer assembly with bacterial cellulose for food packaging materials

Soft Matter. 2023 Oct 18;19(40):7696-7707. doi: 10.1039/d3sm00826f.

Abstract

The pervasive presence of plastic packaging has led to significant environmental contamination due to excessive reliance on petrochemicals and the inherent non-biodegradability of these materials. Both bacterial cellulose (BC) and chitosan (CT) films offer a promising option for food packaging purposes due to their sturdy mechanical strength, biodegradability, environmentally friendly manufacturing process, and non-toxic composition. However, the considerable moisture absorption capacity of these eco-friendly materials has hindered their extensive use, as it leads to a reduction in their strength and ability to serve as a barrier. In the present study, we introduced a composite material of BC reinforced with a lauryl gallate grafted CT coating. After grafting CT with lauryl gallate (CT-LG) through enzymatic modification, it showed excellent hydrophobic properties also in a green route of chemistry synthesis. Based on the results of the study, the duration of the water droplet test of the pure CT-LG film and BC coated with CT-LG (BC/CT-LG) films was more than 15 min, showing that water droplets can be completely blocked by the CT-LG coating without water penetration. For the mechanical properties, the wet flexural strength and wet tensile strength of BC/CT-LG films have improved 400% and 70% compared with the original BC. This method produces a composite material with enhanced hydrophobicity and green properties and shows great potential for use in drinking straws or packaging bags.

MeSH terms

  • Cellulose* / chemistry
  • Chitosan* / chemistry
  • Food Packaging
  • Layer-by-Layer Nanoparticles
  • Water / chemistry

Substances

  • Cellulose
  • Water
  • Chitosan
  • lauryl gallate