Biography Many commonly consumed fruits, vegetables and beverages contain various classes of flavonoids and in varying quantities. Most fruits that are red or purple, such as red grapes, cherries, and blueberries, have substantial quantities of several anthocyanidins. Many of these same foods also contain flavonols, primarily quercetin. Other vegetables that contain quercetin or kaempferol, but at much lower quantities, include broccoli and kale.
Teas provide high concentrations of catechins and small amounts of the flavonol quercetin.
A variety of dimers, trimers, oligomers, and polymers of flavonoids are present in foods. There is a dearth of comprehensive data on the flavonoid content of foods. This is due primarily to the lack of a single, robust analytical system that measures all of the prominent food flavonoids, as aglycones, in a single run. Development of such a system, comprehensive analysis of foods, and subsequent summarization of food flavonoid data into a convenient database will provide the appropriate tools to ascertain the impact of dietary flavonoids on health maintenance and disease prevention. A high-performance liquid chromatography method employing diode array detection was developed to determine levels of the major catechins present in black, green and Jasmine tea infusions.