Evaluation of red pigment extracted from purple carrots and its utilization as antioxidant and natural food colorants

Abstract

Anthocyanins derived from purple carrots were extracted, and identified by using HPLC. Extracted pigments from purple carrots are used as alternative natural red colorants for preparing hard candy and sweet jelly and also red carrot pigment used as natural antioxidant on sunflower oil to delay the rancidity of sunflower oil. Purple carrots contain 168.7mg anthocyanin/100g on fresh weight basis, where the major constituents were Cyanidin-3-xylosyl-glucosyl-galactoside acylated with ferulic acid (33.65%) followed by Cyanidin-3-xylosyl-glucosyl-galactoside acylated with coumaric acid (29.85%) and Cyanidin-3-xylosyl-galactoside (28.70%) as determined by HPLC. Dextrin was the best carrier for purple carrots anthocyanin pigment followed by cellulose, soluble starch and glucose respectively. On the other hand, the highest pigment color stability of anthocyanin derived from purple carrots was obtained at pH values ranged between 1.0 and 4.0 and temperatures ranged between 40 and 80°C, while the degradation ratio of anthocyanin being 15% of total pigments after 180min at 100°C. Antioxidant activities of anthocyanin from purple carrots were assessed by determining peroxide value on sunflower oil during 7days at 60°C. Sunflower oil contained 1000ppm purple carrots extract showed lower peroxide value being (7.90) than using 200ppm synthetic antioxidant (BHT) (8.38) meq/kg. Analysis of variance for sensory evaluation of prepared hard candy and sweet jelly indicated that there were no significant differences for hard candy contains 0.30% and sweet jelly 0.20% anthocyanins pigments from purple carrots and control hard candy and sweet jelly.