Applications of pigmented rice anthocyanins in food packaging: A mini review

Compared to other anthocyanin sources in intelligent food packaging, pigmented rice anthocyanins have received limited attention. This review explores their potential applications, emphasizing their distinct pH-responsive color changes, which make them promising candidates for smart packaging. Pigmented rice and its by-product—rice bran—are rich in anthocyanins and offer economic and environmental benefits as sustainable resources. Additionally, these anthocyanins also exhibit notable thermal stability, advantageous for packaging applications. However, their potential remains underutilized due to challenges in extraction efficiency, limited compositional knowledge, low practical awareness, and stability concerns. Recent studies suggest that non-conventional extraction methods, particularly those combining mechanical-assisted and traditional techniques, can improve both yield and efficiency. Black rice anthocyanins, with higher concentrations, are most commonly used in chitosan-based films to monitor the freshness of protein-rich foods like pork and seafood. While research has mainly addressed stability and leaching under high humidity, color variation remains an overlooked issue. Future work should focus on standardizing anthocyanin color properties. Two strategies are proposed: optimizing extraction across different rice species and applying machine learning to identify key factors—such as rice variety and extraction parameters—that influence color consistency and improve quality control for commercial applications.