Effects of Thermal Treatment on Radical‐scavenging Activity of Single and Mixed Polyphenolic Compounds

Rutin, luteolin, luteolin‐7‐glucoside, and chlorogenic acid gradually decomposed during heating at 100°C. Even though they rapidly decomposed at 180°C, some decomposition products still had radical‐scavenging activity. When rutin was heated in the presence of chlorogenic acid, decomposition of rutin was almost totally inhibited at 100°C, but was reduced at 180°C. These results suggest that the radical‐scavenging activity is more stable than the content of original polyphenolic compounds in foods during cooking and processing.