STABILITY OF ANTHOCYANINS FROM ZEBRINA-PENDULA AND IPOMOEA-TRICOLOR IN A MODEL BEVERAGE

Anthocyanins from two sources with reported high stability, Ipomoea tricolor and Zebrina pendula, were compared with extracts from blackberries containing mainly cyanidin-3-glucoside (Cn-3-G) and a commercial enocyanin. The pigment samples were formulated in a sugar, citrate-phosphate buffer solution for storage at room temperature. Tristimulus color data and pigment retention were measured at periods up to 82 weeks. The Ipomoea pigments were the most stable. Zebrina and Cn-3-G samples were similar followed by enocyanin. Deacylated pigments from both Ipomoea and Zebrina were the least stable indicating that the acyl groups conferred stability.