Boosting Food System Sustainability through Intelligent Packaging: Application of Biodegradable Freshness Indicators

World hunger is getting worse, while one-third of foods produced around the globe is wasted and never consumed. It is vital in reducing food waste to promote the sustainability of agri-food systems. Intelligent packaging embedded with freshness indicators can monitor food freshness in a real-time manner and be deployed for cutting food waste produced due to predetermined expiration date and informing consumers of food safety. Biodegradable halochromic films have been increasingly utilized as freshness indicators because of their low environmental impact. In this review, recent advances in biodegradable halochromic indicators for intelligent packaging are reported. The pH-responsive behaviors of natural pigments, the development of biodegradable solid supports for freshness indicators, the colorimetric response of freshness indicators to food products and simulated models, and future challenges in this field are discussed. Particularly, novel technologies coupled with halochromic indictors are highlighted, including sensor arrays, nanocomposites, smartphone-assisted detection, and ink-free printing.

Automated summary

World hunger worsens, with one-third of global food production being wasted. Promoting sustainability in agri-food systems is crucial to reduce food waste. Intelligent packaging with freshness indicators can monitor food freshness in real-time, cutting waste and ensuring food safety. Biodegradable halochromic films show promise as freshness indicators due to their low environmental impact. This review discusses recent advances in biodegradable halochromic indicators for intelligent packaging, including pH-responsive natural pigments, biodegradable solid supports, colorimetric response, and emerging technologies like sensor arrays and smartphone-assisted detection.