Sesquiterpene lactones in chicory ( Cichorium intybus L.) : Distribution in chicons and effect of storage

Abstract

The bitter taste of chicory is caused by sesquiterpene lactones. The levels of lactucopicrin and lactucin-like sesquiterpene lactones, i.e. lactucin, 8-deoxylactucin and their 11β,13-dihydro derivatives, in chicons from four different chicory cultivars ( Cichorium intybus L.) were determined by ELISA. Data were used to determine the sample size needed for the statistically reliable determination of the levels of sesquiterpene lactones in chicory. The sample size varied from 6 to 12 chicons. No relation between the weight of chicons and the sesquiterpene lactone levels was found. The distribution of sesquiterpene lactones in chicons from two cultivars, i.e. cv. Focus and cv. Monitor, was studied with ELISA. In both cultivars the central axis contained the major part of the sesquiterpene lactones as compared to the proximal and distal parts of the leaves. Storage at 2 °C and 10 °C for up to 13 days had no effect on the level of lactucin-like sesquiterpene lactones in the chicons. After 7 days of storage a slight increase of lactucopicrin content was observed as compared with chicons analysed after 1 and 13 days of storage.