Enhancing Chitosan Films for Egg Packaging Using Cellulose Nanocrystals and Sodium Montmorillonite Nanoparticles

Area of Science:

• Materials Science
• Food Science
• Polymer Science

Background:

• Bio-based polymers often exhibit inadequate barrier properties and mechanical strength for applications like egg packaging.
• Chitosan (CS) is a promising biopolymer, but its limitations necessitate enhancement for effective food preservation.
• Nanoparticles like cellulose nanocrystals (CNC) and sodium montmorillonite (MMT) can improve polymer matrix properties.

Purpose of the Study:

• To enhance the barrier capacity and mechanical strength of chitosan films for egg packaging.
• To evaluate the efficacy of incorporating CNC and MMT nanoparticles into chitosan coatings for preserving fresh egg quality.
• To assess the impact of these bio-nanocomposite coatings on egg storability over five weeks under ambient conditions.

Main Methods:

• Development of chitosan-based bio-nanocomposite films incorporating 5 wt% CNC or MMT.
• Application of these coatings to fresh eggs.
• Evaluation of egg quality parameters (Haugh unit, yolk index, albumen pH) and mass transfer over a 5-week storage period.
• Scanning Electron Microscopy (SEM) to analyze coating structure and pore sealing.

Main Results:

• SEM images confirmed that the coatings effectively sealed eggshell pores, minimizing mass transfer.
• Eggs coated with CS-CNC and CS-MMT exhibited significantly higher Haugh units (67.1 and 64.8, respectively) and yolk indices (0.355 and 0.343, respectively) compared to control and pure CS.
• While effective in preservation, the nanocomposite coatings led to lower albumen pH levels during storage.

Conclusions:

• Chitosan-based nanocomposite coatings containing CNC or MMT show potential for preserving internal egg quality.
• These coatings provide an effective barrier against mass transfer and CO2 loss, extending egg shelf life.
• Further research may be needed to optimize pH maintenance within the egg albumen.