# A Novel Gellan Gum-Chitosan Composite Film Functionalized with Melatonin for Enhanced Preservation of Fresh Blueberries

## TL;DR

A new gellan gum-chitosan film with melatonin helps preserve blueberries longer by reducing spoilage and keeping nutrients.

## Contribution

Melatonin was first incorporated into a gellan gum-chitosan matrix for food preservation.

## Key findings

- The G2C-M50 film showed high tensile strength, flexibility, and moisture barrier.
- Blueberry spoilage dropped to 2.2% with 80.5% anthocyanin retention after 7 days.
- Melatonin's antioxidant and antimicrobial properties enhanced preservation effectiveness.

## Abstract

The demand for sustainable food packaging is increasing. This study developed a novel ternary composite film based on gellan gum (GG), chitosan (CS), and melatonin (MT) for preserving fresh blueberries. For the first time, MT was incorporated as a functional agent into a GG/CS matrix. Films with varying compositions were prepared and characterized. The GG-dominant film with the highest MT content (G2C-M50, 2:1:0.5 w/w) exhibited optimal properties, including high tensile strength, enhanced flexibility, and a superior moisture barrier. In a 7-day storage trial, this film dramatically extended blueberry shelf-life, reducing the spoilage rate to 2.2% while maintaining 80.5% of the initial anthocyanin content. This success is attributed to the synergy between the robust GG/CS physical network and the multifunctional (antioxidant, antimicrobial) activities of MT. This work presents a highly effective strategy for active food packaging.