Horseradish

Its root is used as a vegetable or ground in a condiment called prepared horseradish, and has at times been used as the bitter herbs in the Passover meal in some Jewish communities. Horseradish, sometimes blended with cream and called horseradish sauce, is often served with roast or boiled beef or sausages, as well as smoked fish. Horseradish is also used in some prepared mustards. Also, much of what is styled wasabi is actually common horseradish dyed green.

The horseradish root itself has hardly any aroma. When cut or grated, however, enzymes from the damaged plant cells break down sinigrin (a glucosinolate) to produce allyl isothiocyanate (mustard oil), which irritates the sinuses and eyes. Once grated, if not used immediately or mixed in vinegar, the root darkens and loses its pungency and becomes unpleasantly bitter when exposed to air and heat.

Over two thirds of the world's horseradish is said to be grown in a small region around Collinsville, Illinois in the US, the self-styled "Horseradish Capital of the World", whence it is even exported overseas as a gourmet version of the product to places more renowned for consumption of the root. The biggest US production for domestic supply comes from Silver Springs in Eau Claire,Wisconsin.

It has been speculated that the word is a partial translation of its German name Meerrettich. The element Meer (meaning 'ocean, sea', although it could be derived from the similar sounding Mähren, the German word for Moravia, an area where the vegetable is cultivated and used extensively) is pronounced like the English word mare, which might have been reinterpreted as horseradish. On the other hand, many English plant names have "horse" as an element denoting strong or coarse, so the etymology of the English word (which is attested in print from at least 1597) is uncertain. (The OED contains no reference to the derivation from the German Meer.)

Modern uses

The American fast-food restaurant chain Arby's uses horseradish in its "Horsey Sauce", which is provided as a regular condiment, alongside ketchup, mustard, and mayonnaise. This is not a common practice at its major competitors. In addition, the US fast-food outlet Popeye's serves "quarter pounders with 'radish," in its stores on the East Coast. The reason it doesn't offer this meal in its stores elsewhere is something of a mystery.

Horseradish sauce made from grated horseradish root and cream is a popular condiment in the United Kingdom. It is often served with roast beef, but can be used in a number of other dishes also.

Additionally, since real wasabi is very expensive, even in Japan, most Japanese restaurants around the world actually serve a horseradish mixture that's been dyed green. In fact, some imitation wasabi makers, such as S&B, call horseradish "western wasabi".