Eutrema japonica (Miq.) Koidz. - syn. Wasabia japonica (Miq.) Matsum.; Eutrema wasabi Maxim.; Cochlearia wasabi Siebold - Brassicaceae
Japanese horseradish, Japanischer Meerrettich, Wasabi
Perennial herb, up to 60cm tall, native to Japan, Korea, Sakhalin, cultivated in Japan, Korea and Taiwan for its edible rhizomes (source of the pungent condiment, wasabi).
„Its stem is used as a condiment and has an extremely strong flavor. Its hotness is more akin to that of a hot mustard than that of the capsaicin in a chili pepper, producing vapours that stimulate the nasal passages more than the tongue.“ http://en.wikipedia.org/wiki/Wasabi
Fresh wasabi paste made by crushing the root develops a characteristically fresh greenish flavor clearly different from the flavors of pastes from the other glucosinolates containing plants. LC/GC/MS/1H-NMR showed 6-methylthiohexyl isothiocyanate (2mg/kg), 7-methylthioheptyl isothiocyanate and 8-methylthiooctyl isothiocyanate to be the characteristic greenish wasabi flavor components.
[ω-Methylthioalkyl isothiocyanates in Wasabi. Agricultural and biological chemistry, INA, Kazuo, et al., Vol.53, 1989, 537-538]
The rhizome contains most of the flavour and is the part most widely used, although both the leaves and petioles contain some of the flavour. Wasabi myrosinase liberates a mixture of isothiocyanates from precursor molecules, giving wasabi its distinctive flavour.
[Flavour and pharmaceutical properties of the volatile sulphur compounds of Wasabi (Wasabia japonica). Depree, J.A., Howard, T.M., Savage, G.P., Food research international, 31(5), 1998, 329-337]
The main volatile components of E.wasabi grown in Yunnan were identified as 1,6-hexane diisothiocyanate (30.7%) and allyl isothiocyanate (17.1%) with GC-MS.
[Study on Volatile Components Of Yunnan Eutrema Wasabi Maxim., LU, Li-he, et al. Yunnan Chemical Technology, Vol.5, 2011, 4]
Total content of isothiocyanates of Japanese horseradish rhizome grown in New Zealand was 2067mg/kg fresh weight, with allyl isothiocyanate (AITC, 1937 mg/kg) as the main component. Minor components present were 3-butenyl isothiocyanate (43 mg/kg), 4-pentenyl isothiocyanate (47 mg/kg), sec-butyl isothiocyanate (18 mg/kg), isopropyl isothiocyanate (12 mg/kg) and 5-hexenyl isothiocyanate (7 mg/kg).
[Comparison of flavour compounds in wasabi and horseradish., Sultana, T., Savage, G. P., McNeil, D. L., Porter, N. G., Clark, B., Journal of Food Agriculture & Environment, Vol.1(2), 2003, 117-121] http://www.coppersfolly.co.nz/v1/research/comparison2.pdf