Analysis on contents of rutin and quercetin in tartary buckwheat tea and tartary buckwheat dried noodles

Contents of rutin and quercetin in tartary buckwheat tea and tartary buckwheat dried noodles were analyzed by high-performance liquid chromatography(HPLC).The results indicated that the contents of rutin and quercetin had significant differences between granulated and whole wheat(embryo) tartary buckwheat tea.There was more rutin(0.518 3%～0.850 6%) than quercetin(0.057 3%～0.252 1%) in whole wheat(embryo) tartary buckwheat tea.However,in granulated tartary buckwheat tea and tartary buckwheat dried noodles,the content of rutin(0.029 7%～0.0314% and 0.008 1%～0.024 4% respectively) was much less than quercetin(0.481 6%～1.022 2% and 0.034 9%～0.072 0% respectively).One of the possible explanations is the presence and activity of the rutin degrading enzyme.Rutin transformed to quercetin could be caused by this enzyme found in buckwheat.Rutin was not the main flavonoids in all tartary buckwheat tea and tartary buckwheat dried noodles.So,it was inaccurate to evaluate the quality of buckwheat products only by rutin content and total flavonoids content.