Objective: To investigate the effect of various cooking methods on the contents of major flavonoids in vegetables, and to provide basic data for researches on the relationship between flavonoid and health.
Methods: Nine kinds of vegetables obtained from Tianjin market were cooked by frying, boiling, stewing, microwave cooking respectively, then the contents of flavonoids in vegetables and soups after cooking were determined by HPLC.
Results: The reserving rates of flavonoids after frying, boiling, stewing and microwave cooking ranged from 54.6% to 115.6%, 33.6% to 107.8%, 31.7% to 100.5%, and 43.1% to 109.6% respectively. Parts of flavonoids were also transfered to the soup after cooking. The transferring rate ranged from 1.4% to 55.8%.
Conclusion: Cooking often affected the flavonoids in vegetables in some degree, and various cooking methods exerted different effects on the content of flavonoids.