Horseradish

I've known about horseradish as a pungent spice since childhood through its use in horseradish sauce, but only later came to appreciate its importance in Central and Eastern European cuisines.

Horseradish plants in flower	Horseradish roots and leaves	Dried horseradish roots

Species:	Armoracia rusticana.
Origin:	Mediterranean or Eastern Europe.
Source:	The plant is widely cultivated across Central and Eastern Europe. A "wild" form is commonly found, but this has escaped from cultivation rather than being indigenous.
Used Part:	Root, nearly always used fresh or pickled.
Family:	Brassicaceae (cabbage family).
Effect:	Intact horseradish root does not exhibit much aroma, but on cutting, shredding or grating a pungent and very strong odour is released. This odour is not stable and vanishes after some ten or twenty minutes. Japanese horseradish (wasabi) is nearly indistinguishable from horseradish in taste but a little stronger.
Etymology:	The origin of the botanical genus name armoracia, which has been in use by European botanists for horseradish since the Middle Age, is uncertain but may refer to Brittany (from its Ancient French name Armorica). The old genus name cochlearia "scurvygrass" is derived from the Latin cochleare "spoon" which survives in medical terminology to this day. The word is closely related to Latin cochlea "snail's shell" suggesting that the Romans used shells as spoons.
	The botanical species name rusticanus "rural" from rus "countryside" probably refers to the distribution of horseradish. An obsolete species name lapathifolius "sorrel-leaved" hints at the similar leaf shapes of horseradish and some large-leaved sorrel variants which were known in Old Greek as lapathos.
	The English name horseradish is allegedly derived by misinterpretation of the German meerrettich as "mare radish". On the other hand several English plant names contain an element horse to denote "large" or "strong" and if horseradish follows this approach then the name parallels the German meerrettich. The word radish (German rettich, French radis) itself derives from Latin radix "root". At the basis lies an Indo-European root wrad "branch" or "root". The common appendix of plant names, wort, has the same origin.
	German has two different words for horseradish: meerrettich is preferred in the North, while Southern Germans and Austrians usually call the spice kren. The name meerrettich means "more radish" or "greater radish", indicating the greater size or stronger aroma of horseradish when compared to garden radish raphanus sativus. The similarity of the first element of this name to German meer "sea" is probably coincidental. A similar motivation is also found in French where the name raifort is probably formed from radis fort "strong radish".
	The Southern German term kren is a loan from a Slavonic tongue and cognates are widespread (Czech křen, Russian khren and Polish chrzan) but ultimately of unknown origin. Some other non-Slavonic European languages have also loaned the name, e.g. French cran, Italian cren and Greek chreno. The Northern Germanic names of horseradish (e.g. Danish peberrod, Icelandic piparrót and Swedish pepparrot) mean "pepperroot", being composed of the name of black pepper and an element cognate to English root, which is itself related to the Latin radix. Finnish piparjuuri has the same meaning (juuri "root").
	In Japanese, the horseradish bears names comparing it with the indigenous and popular spice wasabi, namely seiyō-wasabi "Western wasabi" and wasabi-daikon "radish-wasabi". The similarity between the two spices is emphasised by many names of wasabi in Western languages denoting "Japanese horseradish".
Uses:	Horseradish is a very popular spice in Central and Northern Europe, where the fresh root is grated and eaten together with cured ham, cooked meat or roasted meat (e.g. British roast beef). Cured ham with horseradish is a traditional Easter meal in Austria. As the aroma is highly volatile and instable, the lachrymal process of grating may need to be repeated several times during a meal. Some horseradish preservatives are available (usually grated and tinned root with a few stabilising additions) but true lovers of the root think them inferior, although convenient.
	As the pungent allyl isothiocyanate is not heat resistant, horseradish is seldom used for warm foods and added immediately before serving. Even in cold water, allyl isothiocyanate is not stable for longer than a few minutes. However, in sour environments the hydrolysis of thiocyanates takes place much more slowly.
	In Austria, freshly grated horseradish (or the tinned product) is frequently mixed with grated apples (sour varieties preferred or some lemon juice added) and then eaten as a spicy relish to fried or cooked meat. This mixture, apfelkren, can be stored for about a day without substantial loss in pungency. To prevent darkening of the apples (enzymatic oxidation of phenolic compounds) they may steamed briefly before mashing to give a softer, smoother texture.