Montmorillonite-Reinforced Starch Films: Recent Advances in Nanocomposite Design for Sustainable Food Packaging

Abstract

The increasing demand for sustainable packaging materials has led to growing interest in biodegradable alternatives to petroleum-based plastics. Starch-based films are renewable and compostable, yet their application in food packaging is limited by poor mechanical and barrier properties. This review presents recent advances in the development of Montmorillonite (MMT)-reinforced starch films, highlighting their improved structural, thermal and functional performance. The mechanisms of reinforcement, intercalation, exfoliation and network formation, are discussed in relation to polymer–clay interactions and film morphology. Special emphasis is placed on the role of these nanocomposites in food preservation. Case studies demonstrate their capacity to extend shelf life by reducing moisture loss, microbial spoilage and oxidative degradation in perishable products such as strawberries, paneer, chicken and litchi. Intelligent applications, such as spoilage detection through pH-induced color changes, are also explored. Comparative tables summarize mechanical, thermal and barrier improvements across formulations. Finally, key challenges related to large-scale processing, nanoparticle dispersion, compostability and cost-efficiency are addressed. Future research is encouraged to explore agro-industrial starch sources, green modification strategies and hybrid systems to enable sustainable, high-performance packaging. MMT–starch films thus represent a promising platform for active food preservation aligned with circular economy and environmental goals.