Evaluation and modification of processing techniques for recovery of anthocyanins from colored corn

Color is the most important indicator of taste and flavor, both vital sensory properties of food and beverages. The processing industry commonly uses artificial food colorants derived from petroleum or coal, called coal tar dyes. These dyes may cause attention-deficit/hyperactivity disorder, genotoxicity, neurotoxicity and/or carcinogenicity. In an era of “natural ingredients”, there is increasing customer pressure for exploring natural alternatives of synthetic dyes. Anthocyanins can be used as a replacement of synthetic FD&C Red 40 dye. However, their recovery from conventional sources is uneconomical due to higher inputs and lower economic value of the processing residues. The potential of using colored corn as a viable source of anthocyanins was explored. Anthocyanins containing purple and blue corn were fractionated using laboratory scale wet milling, dry milling and dry grind processes; coproduct yields were compared with those from conventional yellow dent corn. In wet milling, starch yields of colored corn were 6.7 to 8.7% less than conventional yellow dent corn on dry basis (db). In dry milling, large grit yields of colored corn were