Allium ampeloprasum L. - Liliaceae - (wild) leek, (Sommer-) Lauch, Porree, Ackerknoblauch

Allium ampeloprasum var.porrum (L.) J.Gay = Allium porrum L.
„Leek cultivars may be treated as a single cultivar group, e.g. as Allium ampeloprasum 'Leek Group'… Leeks have a mild onion-like taste. In its raw state, the vegetable is crunchy and firm. The edible portions of the leek are the white base of the leaves (above the roots and stem base), the light green parts, and to a lesser extent the dark green parts of the leaves.“
https://en.wikipedia.org/wiki/Leek

„… methyl propyl disulfide and dipropyl trisulfide are very characteristic aroma compounds in leeks… the balance between leek-flavour and off-flavour is worsened during long time of storage of unblanched leek, while blanched leek is more stable, but with less intense flavour.“
[Influence of blanching on aroma compounds in leeks during frozen storage., Petersen, M.A., Poll, L., Lewis, M., Holm, K., Flavour Science: Recent Developments, 197, 1996, 245-249]

„The odor active compounds in freshly cut leek slices and in blanched and unblanched leek slices stored for 12 months were investigated by a detection frequency method. Fifteen judges were evaluating the three samples randomized. The most important aroma compounds in the freshly cut leek slices were dipropyl disulfide, methyl propenyl disulfide, pentanal, decanal, and propyl propenyl disulfide in order of priority. When stored frozen and unblanched for 12 months, the aroma composition changed and the most important compounds became pentanal, decanal, 2,5-dimethyl furan, unknown compound I, and dipropyl disulfide. Blanching before freezing prevented to some degree these changes but also reduced the perceived intensity of the aroma compounds. The most important aroma compounds in the blanched sample were dipropyl disulfide, unknown compound I, pentanal, 2,5-dimethyl furan, and propyl propenyl disulfide. “
[Determination of odor active aroma compounds in freshly cut leek (Allium ampeloprasum var. Bulga) and in long-term stored frozen unblanched and blanched leek slices by gas chromatography olfactometry analysis., Nielsen, G.S., Poll, L., Journal of agricultural and food chemistry, Vol.52(6), 2004, 1642-1646]

3-Mercapto-2-methylpentan-1-ol is also a potent aroma compound of cooked leek, „… cooking of leek was most effective in generating the thiol, because the amount analyzed in the cooked sample was 11-fold higher than in the uncooked material…“
[Quantitation of the intense aroma compound 3-mercapto-2-methylpentan-1-ol in raw and processed onions (Allium cepa) of different origins and in other Allium varieties using a stable isotope dilution assay., Granvogl, M., Christlbauer, M., Schieberle, P., Journal of agricultural and food chemistry, Vol.52(10), 2004, 2797-2802]

allium_porrum.jpg
Allium ampeloprasum L. as Porrum capitatum, syn. Allium porrum L.
Fuchs, L., New Kreüterbuch, t.361 (1543)
http://plantgenera.org/species.php?id_species=39216


Allium ampeloprasum var.ampeloprasum cultivar 'elephant garlic': „The mature bulb is broken up into cloves which are quite large and with papery skins and these are used for both culinary purposes and propagation.“
https://en.wikipedia.org/wiki/Elephant_garlic

„(Z)-Propanethial S-oxide (onion lachrymatory factor), absent in garlic, is found to be formed from crushed elephant garlic (Allium ampeloprasum), consistent with the classification of this plant as a closer relative of leek than of garlic. Mixtures of thiosulfinates, lachrymatory thial S-oxides, and related compounds are directly observed from crushed leek (Allium porrum) and Chinese chive (Allium tuberosum).“
[Applications of direct analysis in real time mass spectrometry (DART-MS) in Allium chemistry. 2-Propenesulfenic and 2-propenesulfinic acids, diallyl trisulfane S-oxide, and other reactive sulfur compounds from crushed garlic and other Alliums., Block, E., Dane, A.J., Thomas, S., Cody, R.B., Journal of agricultural and food chemistry, Vol.58(8), 2010, 4617-4625]

plantgenera.org_illustrations_hd_153393.jpg
Allium ampeloprasum L. var. babingtonii
English Botany, or Coloured Figures of British Plants, ed.3 [B] [J.E. Sowerby et al], vol.9, t.1531 (1869)
http://plantgenera.org/species.php?id_species=39216