Influence of harvest date on inulin chain length distribution and sugar profile for six chicory (Cichorium intybus L) cultivars

The influence of harvest date on inulin chain length distribution, as well as on the profile of glucose, fructose and sucrose of six different chicory cultivars previously not grown in the northern part of Europe was investig ated. Inulin was extracted from both air- and freeze-dried chicory roots an d analysed by means of high-performance anion-exchange chromatography with pulsed amperometric detection. Glucose, fructose and sucrose profiles were calculated relative to the total content of these sugars and inulin. The hi ghest weight average degree of polymerization (<(DP)over bar>(w)) for inuli n was detected for the cultivars Bergues and Tilda (<(DP)over bar>(w) 17.6) . The longest average inulin chains for all cultivars were found when harve sting chicory during mid and late October, and a significant decrease in <( DP)over bar>(w) was observed for all cultivars in November in connection wi th the weather turning colder. Concomitantly, sucrose levels increased sign ificantly. Glucose and fructose levels were found to decrease until mid Oct ober and thereafter to increase slightly. (C) 1999 Society of Chemical Indu stry.