Chitin Nanofiber/Chitosan Coatings for Food Shelf-life Extension

Chitin nanofibers (ChNFs) were successfully isolated from shrimp shell waste using a combination of chemical and mechanical treatments. These extracted nanofibers were incorporated into chitosan to fabricate composite films. The addition of ChNFs reduced the water content in the chitosan films from 121.0% to 79.1% and decreased the water contact angle from 98.1° to 86.3°. This indicated that the ChNF/chitosan films became more hydrophobic. Furthermore, the incorporation of ChNFs significantly enhanced the mechanical and barrier properties of the films. The ChNF/chitosan coating was subsequently applied to banana surfaces, resulting in reduced weight loss during storage compared to uncoated bananas and those coated with only chitosan. After 12 days of storage, the weight loss in the ChNF/chitosan-coated bananas was 17.1%, compared to 23.2% in uncoated bananas and 19.7% in chitosan-coated bananas. This improvement is attributed to the superior barrier properties of the ChNF/chitosan films, which delayed gas permeation. These findings suggest that the ChNF/chitosan coatings have potential for extending the shelf-life of food products.