Black carrot (Daucus carota ssp sativus) juice: Processing effects on antioxidant composition and color

Black carrot, a potential source of anthocyanin pigment, has high antioxidant activity. The effect of pre-press maceration treatment with different doses of cell wall degrading enzyme pectinase (Aspergillus niger Teigh) on antioxidant composition of black carrot juice was investigated. Enzyme-assisted processing significantly (p < 0.05) improved the antioxidant composition of black carrot juice. There was an overall increase of 33% in juice yield, 27% in total phenolics and 46% in total flavonoids. The total anthocyanin content in black carrot juice was almost doubled. The in vitro total antioxidant activity in black carrot juice extracted through enzyme-assisted processing was 30.0 and 62.0 mu mol TE/mL in ferric reducing antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays, respectively. There was 30% increase in total antioxidant activity of black carrot juice extracted with enzyme over straight pressed juice. The results indicate that tailoring of specific enzyme mixtures can yield antioxidant rich juice products. Optimizing a strategy for extraction of phenolic rich juice from black carrots can offer an opportunity for its utilization in developing novel functional beverages with enhanced color appeal and high antioxidant activity. (C) 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.