Anthocyanins (ACNs), a major class of water-soluble flavonoid pigments, are responsible for the vivid red, purple, and blue hues in many edible ornamental flowers. Recently, increasing attention has been directed toward these flowers not only for their aesthetic value but also for their nutritional and functional potential, such as antioxidant, anti-inflammatory, antidiabetic, anticancer, and cardioprotective activities. This review summarizes current knowledge on the source and biosynthesis pathways of ACNs in edible ornamental flowers, highlighting the key enzymes and regulatory genes involved. Factors affecting ACN stability, such as chemical structure, pH, temperature, light, oxygen, water activity, copigmentation, and microencapsulation are discussed in detail to provide insights into preserving their color and functionality in food systems. Eight extraction techniques, including solvent extraction (conventional method), and ultrasound-assisted, microwave-assisted, pulsed electric field-assisted, cold plasma-assisted and green solvent methods, are compared in terms of efficiency, sparing energy, environmental impact, and scalability. Among the 11 different types of edible flowers, the top four for total ACNs (g cyanindin-3-glucoside/kg DB) are rose (33.3), saffron (10.2), roselle (10.0), and butterfly pea flower (3.5), making them good sources of red to blue ACNs for exploring industrial scale-up. Finally, the review explores their diverse applications in the food industry as natural colorants, functional ingredients, and intelligent packaging films, offering potential for clean-label and health-oriented products. Overall, edible ornamental flowers represent a sustainable and multifunctional source of ACNs with promising applications in both nutrition and food technology. Future directions should focus on enhancing ACN stability, reducing extraction costs, and validating their efficacy through in vivo studies and industrial-scale trials.
Lin et al. (Thu,) studied this question.