Thermal Degradation Kinetics of Three Kinds of Representative Anthocyanins Obtained from Blood Orang

Cyanidin-3-glucoside, cyanidin-3-(6′′-malonyl)-glucoside, and cyanidin-3-glucoside-derived pyranoanthocyanins which were three major anthocyanins of blood orange, were obtained using a Toyopearl TSK HW-40S column chromatography. Then, thermal degradation kinetics of the three major anthocyanins was studied at selected temperatures (70, 80, and 90°C). Degradation parameters such as k and t1/2 values were determined. The activation energy (Ea) values for cyanidin- 3-glucoside, cyanidin-3-(6′′-malonyl)-glucoside and cyanidin-3-glucoside-derived pyranoanthocyanin were 75.4, 79.5, and 81.7 kJ mol-1, respectively. Ea values suggested that cyanidin-3-glucoside-derived pyranoanthocyanin had the highest stability, followed by cyanidin-3-(6′′-malonyl)-glucoside and cyanidin-3-glucoside. However, t1/2 values indicated cyanidin- 3-glucoside-derived pyranoanthocyanin degraded faster than cyanidin-3-(6′′-malonyl)-glucoside and cyanidin-3-glucoside at selected temperature.