Valorization of black carrot industrial residues for the anthocyanin pigment production

Abstract

Abstract Black carrot industrial residues were valorized for their use as raw material for production of anthocyanin pigments, which were obtained as concentrated extracts and microcapsules. The anthocyanins were extracted by citric, tartaric, and lactic acids to maintain the anthocyanins. In turn, concentrated extracts were obtained by 80% of water reduction, whereas microcapsules were prepared through gum arabic and drying methods. The products were analyzed by the effect of pH and temperature on anthocyanins content and coloration. In addition, the shelf-life of pigment products was determined for 360 days of storage at 4°C and 20°C, measuring anthocyanins concentration, color, and phenols retention. Black carrot residues resulted in an excellent material for pigments products preparation. Concentrated extracts achieved up to 7000 mg/L of anthocyanins, high antioxidant activity and dark red color. In order, these products maintained high color stability at pH 2–7 ranges and temperature exposition ranges of 20–90°C. Furthermore, the concentrated extract storage showed 80% of anthocyanins preservation at 4°C and 90% of color retention for 360 days. Anthocyanin microcapsules exhibited 280 mg/L of anthocyanins with pink red coloration, maintaining 50% of anthocyanins for 180 days at temperature storage of 20°C.