witloof chicory forcing
process / process-witloof-forcing
ウィットルーフの軟白栽培
Witloof chicory forcing is a process that regrows cold-stored chicory roots in darkness under controlled temperature and humidity (traditionally beneath a covering of soil, but now mainly in multi-tier hydroponic dark rooms), forming new leaves called chicons.
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Reading the bitterness
Witloof chicory forcing cultivates cold-stored chicory roots for about 3 weeks in a multi-tier hydroponic system at 15–16°C in darkness, producing white new leaves (chicons).
During this forcing process, sesquiterpene lactone levels in the root (FR) tissue left after forcing clearly increase. In root tissue of cv. Sweet Lady after 12 months of refrigerated storage, lactucin was reported to increase from 51.3±5.5 before forcing to 128.3±9.6 μg/g dry weight afterward.
In the same root tissue, lactucopicrin was also reported to rise from 31.5±9.5 to 75.8±1.5 μg/g dry weight, and dihydrolactucin (the reduced form of lactucin) from 10.0±1.0 to 54.5±6.2 μg/g dry weight. These increases, however, were found in the residual root tissue after forcing, not in the head (chicon) that is actually eaten. Separately, no significant change in sesquiterpene lactone levels in the edible part with root storage duration has been reported, so forcing may not affect bitter constituents uniformly in the root and edible part.
Sources for this overview
Checked for this overview: Used to substantiate the temperature, duration, and steps of forcing. / Used to substantiate the numerical increase in lactucin in root tissue. / Used to substantiate the numerical increase in lactucopicrin in root tissue. / Used to substantiate the numerical increase in dihydrolactucin in root tissue.
Follow the connections
witloof chicory →is processed by→ witloof chicory forcing
witloof chicory forcing →increases→ lactucin →contributes to→ bitterness
witloof chicory forcing →increases→ lactucopicrin →contributes to→ bitterness
witloof chicory forcing →increases→ 11(S) 13-dihydrolactucin →is correlated with→ bitterness
Structured claims — open a section to read each claim's confidence, evidence and limits
How processing and cooking change it (4)
Scope: The forcing process after cold storage of roots.
Note: Based on van Arkel et al. (2022): roughly 3 weeks in a multilevel hydroponic system in darkness at 15–16°C.
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ingredient-witloof-chicory —is_processed_by→ process-witloof-forcingScope: Forced root (FR) tissue, cv. Sweet Lady, 12 months of storage
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process-witloof-forcing —increases→ compound-lactucinScope: Residual root-stock (FR) tissue following forcing; cv. Sweet Lady; 12 months storage.
Note: Same as above.
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process-witloof-forcing —increases→ compound-lactucopicrinScope: Root (FR) tissue after forcing, cv. Sweet Lady, 12 months of storage.
Note: Same as above.
Show data
process-witloof-forcing —increases→ compound-11-13-dihydrolactucin