UV degradation of sesquiterpene lactones in chicory extract: Kinetics and identification of reaction products by HPLC-MS

Inulin, a valuable food ingredient, can be extracted from chicory roots (Cichorium intybus L.). However, the direct use of this material is limited, because of the presence of extremely bitter, co-extracted sesquiterpene lactones. Lactucin, a major component, has been degraded by UV irradiation, a process which showed neither temperature (293- 313 K) nor initial concentration dependence. An overall half life time of ca. 45 min was determined. The degradation product was identified by HPLC-MS and H-1 NMR and was the result of the addition of a water molecule on the lactucin C(1)-C(10) double bond, with the OH group located at the C(10) position.