Chicory

Botanical Profile

Cichorium intybus is a perennial to biennial species of the Asteraceae with blue ray florets and a strong taproot. From a raw-material perspective, root, herb, leaves, chicory shoots, radicchio forms and roasted-root products must be clearly distinguished.

Cichorium intybus L. is a herbaceous plant with a strong taproot, basal leaf rosette, branched stems and conspicuous, usually light-blue flower heads. The species occurs in Europe, western Asia and North Africa and is widespread along roadsides, on ruderal sites, meadows and dry habitats. Cultivation and selection have produced various forms of use: root chicory for roasted coffee substitutes and inulin production, witloof chicory as a blanched shoot, radicchio and sugarloaf as leafy vegetables, and wild forms with bitter herb. Botanically, these cultivated forms belong to the same species but differ in morphology, processing and raw-material profile. The taproot is particularly rich in storage compounds, while leaves and shoots are more strongly characterised by bitter compounds and fresh-leaf metabolites.

Phytochemistry

Chicory root contains inulin and other fructans, as well as sesquiterpene lactones, phenolic acids, coumarins, minerals and soluble dietary fibre. The bitterness of the herb and root is associated primarily with sesquiterpene lactones such as lactucin, lactucopicrin and related compounds. Roasted-root products additionally contain roasting products, melanoidins and an altered aroma profile. Chicory and radicchio leaves have their own profiles of bitter compounds, polyphenols, anthocyanins in red cultivars, fibre and mineral accompanying constituents. Inulin fractions from the root differ substantially from bitter-compound-rich herb or leaf preparations. Cultivar, plant part, harvest time, roasting, drying and extraction solvent considerably influence composition.

Traditional Uses

Chicory is firmly established in European herbal, vegetable and food history. The root was historically roasted and used as a coffee substitute or coffee additive, particularly during periods of limited coffee availability. Leaves and young shoots were used as bitter vegetables; cultivated forms such as witloof chicory and radicchio developed from this tradition. In traditional herbal knowledge, the plant was valued for its bitter character. Its cultural-historical importance therefore rests on several lines of use: bitter herb, root raw material, vegetable, fibre source and roasted product. Each of these contexts depends on the specific plant part and processing.

Current Research

Current research on Cichorium intybus addresses inulin and prebiotics, bitter compounds, sesquiterpene lactones, polyphenols, chicory and radicchio breeding, roasted products, food technology and by-product utilisation. Inulin from chicory root is an important dietary-fibre raw material and is studied technologically and nutritionally. Bitter-compound and polyphenol fractions are examined in analytical and experimental models. Roasted chicory is studied with regard to aroma formation, acrylamide management and process quality. Findings on inulin fractions cannot be transferred to bitter-compound-rich herb or leaf extracts.

Sources

• Plants of the World Online: Cichorium intybus L.; Royal Botanic Gardens, Kew.
• Scientific literature on Cichorium intybus, inulin and sesquiterpene lactones.
• Food-technology literature on chicory, radicchio and roasted chicory.