Anthocyanin-Modified Starch-Cellulose-Based Bioplastic Films as a Smart Labels for Shrimp Freshness Monitoring

Abstract

Food waste is a critical global issue, with approximately one-third of total food production lost or wasted annually along the supply chain. Shrimp, owing to its high perishability, is particularly susceptible to spoilage, while its freshness is commonly assessed using destructive methods that do not enable real-time monitoring. This study reports the development of innovative starch–cellulose-based bioplastic films incorporated with anthocyanins extracted from Melastoma malabathricum fruit (MMF) as smart labels for real-time monitoring of shrimp freshness. The bioplastic films were fabricated using the solution-casting method with water hyacinth (WH), corn starch, and glycerol, followed by the incorporation of MMF anthocyanins as natural pH-sensitive indicators. The addition of anthocyanins improved the mechanical properties of the bioplastic films, with tensile strength and elongation at break reaching 8.29 MPa and 13.62%, respectively. The films exhibited distinct and reversible color changes from purple to red under acidic conditions and from purple to yellow-brown under alkaline conditions. During real-time shrimp freshness monitoring, the films showed a progressive color transition from purple to yellow-brown, corresponding to the accumulation of volatile basic nitrogenous compounds generated during protein degradation. These findings demonstrate that MMF anthocyanin-incorporated starch–cellulose-based bioplastic films have potential as smart labels for real-time shrimp freshness monitoring in food-packaging systems, thereby contributing to efforts to reduce food waste.