Flavonoid C-glycosides from pigeon pea leaves as color and anthocyanin stabilizing agent in blueberry juice

The influences of flavonoid C-glycoside extracts from pigeon pea leaves (FCGE) and its main components vitexin and orientin on the color and anthocyanins stability of blueberry juice were investigated in the thermal experiments. The color of juice was enhanced by FCGE and its main components in a molar ratio of 1:1 (anthocyanins/copigment). The saturated color of juice with FCGE and its main components could hold for a significantly longer time. Additionally, copigment FCGE, vitexin and orientin significantly enhanced the stability of anthocyanins. Half-life of anthocyanins in juice samples with FCGE (1:1), orientin and vitexin increased 87%, 79%, and 62%, respectively. These results indicated FCGE showed dramatic effect on the color and anthocyanins stability of juice. Furthermore, juice samples with copigments possessed higher total phenolics content and higher DPPH radical-scavenging activity. Therefore, natural, easily available, inexpensive FCGE has potential as color enhancer and anthocyanins stabilizer in food industry. (C) 2014 Elsevier B.V. All rights reserved.