A comprehensive review of intelligent packaging materials based on biopolymers: Role of anthocyanins, type and properties of materials, and their application in monitoring meat freshness.

The demands of consumers for meat safety and quality have promoted the rapid development of clear, intuitive, low-cost, and real-time monitoring technologies for meat freshness. Anthocyanins-based materials can be used to monitor meat freshness by providing intuitive information of meat freshness, thus effectively avoiding the supply and consumption of spoiled meat. The complex physical and chemical changes inside the package are transformed into intuitive and recognizable color signals by anthocyanins-based materials. Therefore, this review comprehensively examined the recent advances on four materials based on anthocyanins and biopolymers including film, hydrogel, aerogel, and colorimetric sensor array for monitoring meat freshness. The etiology of meat spoilage and effects of anthocyanins addition on the performance of four materials were also investigated. Furthermore, the limitations existing in the production and application of anthocyanins-based materials are discussed and the corresponding countermeasures are proposed. The findings indicated that anthocyanins-based materials had great potential as indicative packaging of meat freshness, but their sensitivity and stability still need to be further improved. Furthermore, the combination of anthocyanins-based materials, smartphone, machine learning, computer vision, and novel chemometrics methods are crucial for the progress of anthocyanins-based materials.