Natural colorants from edible flowers: exploring pigment profiles, phenolic richness, and antioxidant potential

Colour is a key factor influencing food acceptance, and concerns over synthetic dyes have increased interest in natural alternatives. This study conducted a preliminary screening of edible flowers (Calendula officinalis L., Tropaeolum majus L., Hibiscus acetosella, and Viola tricolour L.) as sources of pigments, phenolics, and antioxidants. Extract yield, total phenolic content, antioxidant activity (DPPH), pigment composition (carotenoids, anthocyanins, chlorophylls), and instrumental colour were determined. All extracts showed high yields, especially red T. majus (38%), and strong antioxidant activity (88% radical scavenging). Violet V. tricolour had the highest phenolic content (2658 mg/100 g DW), while H. acetosella presented the highest anthocyanin (250.1 mg/100 g DW) and carotenoid (45.2 mg/100 g DW) levels. Orange T. majus, H. acetosella, and purple and red V. tricolour stood out as promising natural colourants due to high phenolic and antioxidant levels. Further studies should explore their application in various food matrices and nutritional value.