Abstract:The objective of this study was to investigate the effects of quercetin and rutinum（0，0.1，0.2，1，2 mmol/L）on the protein side chain structure of myofibrillar protein（MP）in hydroxyl radical oxidation system.Results showed that with the increase of rutinum concentration，free sulfydryl content was increased significantly compared to control（p＜0.05），especially treated with 1 mmol/L and 2 mmol/L.The BPB content was increased gradually after quercetin and rutinum gradually increased from 0 to 2 mmol/L.Under oxidation conditions，the fluorescence intensity of tryptophan and dityrosine gradually decreased with the increase of quercetin and rutinum concentration from 0 to 2 mmol/L.The quercetin and rutinum can protect the structure of myofibrillar protein under oxidation conditions.