Research progress on anthocyanin-based intelligent pH indicator films

Abstract

With the continuous consumer demands for the improvement of food safety, quality, and freshness preservation, food packaging technology is rapidly evolving. Although traditional packaging materials have barrier and protective functions, they lack the capability for real-time monitoring of food quality and transmitting information. Intelligent packaging, as a novel technological system, not only ensures food safety but also enables intuitive monitoring of food quality. Natural pigments represented by anthocyanins have become a cutting-edge direction in research into intelligent packaging films because of their remarkable pH sensitivity and multiple biological activities. This paper systematically reviews the chemical structure and physicochemical properties of anthocyanins, and the selection of substrate materials and film-forming mechanisms for intelligent packaging films. The functional characteristics and application examples of anthocyanin-based intelligent pH indicator films in meat products, aquatic products, fruits, vegetables, and dairy products are discussed. In light of research from the past five years, the advantages of being eco-friendly and enabling visual monitoring of food's freshness, and the limitations of poor stability and susceptibility to environmental interference of anthocyanin-based intelligent packaging films are analyzed in this review. Future development trends are presented, aiming to provide a reference for subsequent research and industrial applications.

Keywords

Anthocyanins / pH indicator films / Intelligent packaging / Food preservation

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