'Wasabi' (, 山葵 (originally written 和佐比)) ; ''Wasabia japonica'', ''Cochlearia wasabi'', or ''Eutrema japonica'') is a member of the
cabbage family. Known as
Japanese
horseradish, its root is used as a
spice and has an extremely strong flavor. Its hotness is more akin to that of a hot
mustard than the
capsaicin in a
chili pepper, producing vapors that irritate the
nasal passages more than the
tongue. The plant grows naturally along stream beds in mountain river valleys in Japan. There are also other species used, such as ''W. koreana'', and ''W. tetsuigi''. The two main
cultivars in the marketplace are ''W. japonica'' var. ''Duruma'' and ''Mazuma'', but there are many others.
Uses
Wasabi is generally sold either in the form of a root, which must be very finely grated before use, or as a ready-to-use paste, usually in tubes approximately the size and shape of travel
toothpaste tubes. Once the paste is prepared it should remain covered until served to protect the flavor from evaporation. For this reason,
sushi chefs usually put the wasabi between the fish and the
rice.
Fresh leaves of wasabi can also be eaten and have some of the hot flavor of wasabi roots. They can be eaten as wasabi salad by pickling overnight with a salt and vinegar based dressing, or by quickly boiling them with a little
soy sauce. Additionally, the leaves can be battered and
deep-fried into
chips.
For those who mistakenly consume too much of this condiment, the burning sensations it can induce are short-lived compared to the effects of
chili peppers, especially when
water is used to dissipate the flavor.
Wasabi is often served with
sushi or
sashimi, usually accompanied with soy sauce. The two are sometimes mixed to form a single dipping sauce known as Wasabi-joyu.
Legumes may be roasted or fried, then coated with a wasabi-like mixture (usually
an imitation); these are then eaten as an eye-watering "in the hand" snack.
Wasabi Ice Cream is a recent but increasingly popular innovation.
Wasabi and imitations

A tube of imitation wasabi
Almost all sushi bars in America and Japan serve imitation (''seiyō'') wasabi (see Etymology section, below) because authentic wasabi is extremely expensive. Few people, even in Japan, realize that the wasabi that they consume is in fact an imitation. Although very hard to find, real wasabi powder (from ''Wasabia japonica'' plant) is a convenient way to experience true wasabi's remarkable flavor, but most commercially available "wasabi" powders contain no true wasabi at all. Most utilize a powdered imitation made from
horseradish, mustard seed, and green food coloring (sometimes
Spirulina). Whether real or imitation the powder is mixed with an equal amount of water to make a paste.
To distinguish between the true variety of wasabi and the imitation product, real wasabi is known in Japan as ''hon-wasabi'' (本山葵), meaning original, or true wasabi.
Chemistry
The chemicals in wasabi that provide its unique flavor are the
isothiocyanates, including:
★ 6-methylthiohexyl isothiocyanate,
★ 7-methylthioheptyl isothiocyanate and
★ 8-methylthiooctyl isothiocyanate.
Research has shown that isothiocyanates have beneficial effects such as inhibiting
microbe growth. This may partially explain why wasabi is traditionally served with
seafood, which spoils quickly. However, if the quality of seafood is questionable, it should not be eaten raw, with or without wasabi. It is not a treatment for
food poisoning.
Cultivation

A drawing of a wasabi plant, published in 1828 by Iwasaki Kanen.
Few places are suitable for large-scale wasabi cultivation, and cultivation is difficult even in ideal conditions. In Japan, wasabi is cultivated mainly in these regions:
★
Izu peninsula, located in
Shizuoka prefecture
★
Nagano prefecture
★
Shimane prefecture
★
Yamanashi prefecture
★
Iwate prefecture
There are also numerous artificially cultivated facilities as far north as
Hokkaidō and as far south as
Kyūshū. The demand for real wasabi is very high. Japan has to import a large amount of it from:
★
Mainland China and
★
Ali Mountain of
Taiwan
★
New Zealand.
In North America, a handful of companies and small farmers are successfully pursuing the trend by cultivating ''Wasabia japonica''. While only the
Pacific Northwest and parts of the
Blue Ridge Mountains provide the right balance of climate and water for natural cultivation of sawa (water grown) wasabi, the use of hydroponics and greenhouses has extended the range.
★
British Columbia,
Canada
★
Oregon,
United States
★
North Carolina, United States
While the finest sawa wasabi is grown in pure, constantly flowing water, without pesticides or fertilizers, some growers push growth with
fertilizer such as
chicken manure, which can be a source of downstream pollution if not properly managed.
Preparation
Wasabi is often grated with a metal
oroshigane, but some prefer to use a more traditional tool made of dried
sharkskin (鮫皮) with fine skin on one side and coarse skin on the other. A hand-made grater with irregular teeth can also be used.
Etymology
The two
kanji characters "山" and "葵" do not correspond to their pronunciation: as such it is an example of
gikun. The two characters actually refer to the ''mountain hollyhock'', as the plant's leaves resemble those of a member of the
Malvaceae family, in addition to its ability to grow on shady hillsides. The word, in the form 和佐比, first appeared in
918 in ''The Japanese Names of Medical Herbs'' (本草和名 ''Honzō Wamyō''). Spelled in this way, the particular
kanji are used for their phonetic values only.
In Japanese,
horseradish is known as , or "Western wasabi".
See also
★
Aquatic plants
References
External links
★ http://www.mangajin.com/mangajin/samplemj/Wasabi/wasabi.htm
★ http://www.hort.purdue.edu/newcrop/proceedings1993/V2-051.html#Wasabi
★
Technical information about wasabi
★ "Bactericidal activity of wasabi (Wasabia japonica) against Helicobacter pylori" Shin IS, Masuda H, Naohide K. Int J Food Microbiol. 2004 Aug 1;94(3):255–61.
[1]