_Horse-radish_; F. _Raifort_ (_i.e._ _racine forte_), _Cran de
Bretagne_; G. _Meerrettig_.
=Botanical Origin=—_Cochlearia Armoracia L._, a common perennial with
a stout tapering root, large coarse oblong leaves with long stalks,
and erect flowering racemes 2 to 3 feet high. It is indigenous to the
eastern parts of Europe, from the Caspian through Russia and Poland to
Finland. In Britain and in other parts of Europe from Sicily to the
polar circle, it occurs cultivated or semi-wild; in the opinion of
Schübeler[302] it is not truly indigenous to Norway.
=History=—The vernacular name _Armon_ is stated by Pliny[303] to be
used in the Pontic regions to designate the _Armoracia_ of the Romans,
the Wild Radish (ῤαϕανὶς ἀγρία) of the Greeks, a plant which cannot be
positively identified with that under notice.
Horse-radish is called in the Russian language _Chren_, in Lithuanian
_Krenai_, in Illyrian _Kren_, a name which has passed into several
German dialects, and as _Cran_ or _Cranson_ into French.
From these and similar facts, De Candolle[304] has drawn the conclusion
that the propagation of the plant has travelled from Eastern to Western
Europe.
Both the root and leaves of horse-radish were used as a medicine
and also eaten with food in Germany and Denmark during the middle
ages.[305] But the use of the former was not common in England until
a much later period. The plant is mentioned in the _Meddygon Myddfai_
and was known in England as _Red-cole_ in the time of Turner, 1568,
but is not quoted by him[306] as used in food, nor is it noticed by
Boorde,[307] 1542, in his chapter on edible roots. Gerarde[308] at the
end of the 16th century remarks that horse-radish—“is commonly used
among the Germans for sauce to eat fish with, and such like meats, as
we do mustard.” Half a century later the taste for horse-radish had
begun to prevail in England. Coles[309] (1657) states that the root
sliced thin and mixed with vinegar is eaten as a sauce with meat as
among the Germans. That the use of horse-radish in France had the same
origin is proved by its old French name _Moutarde des Allemands_.
The root to which certain medicinal properties had always been
assigned, was included in the materia medica of the London
Pharmacopœias of the last century under the name of _Raphanus
rusticanus_.
=Description=—The root which in good ground often attains a length
of 3 feet and nearly an inch in diameter, is enlarged in its upper
part into a crown, usually dividing into a few short branches each
surmounted by a tuft of leaves, and annulated by the scars of fallen
foliage; below the crown it tapers slightly, and then for some distance
is often almost cylindrical, throwing off here and there filiform
and long slender cylindrical roots, and finally dividing into two or
three branches. The root is of a light yellowish-brown; internally it
is fleshy and perfectly white, and has a short non-fibrous fracture.
Before it is broken it is inodorous, but when comminuted it immediately
exhales its characteristic pungent smell. Its well-known pungent taste
is not lost in the root carefully dried and not kept too long.
[302] _Pflanzenwelt Norwegens_ (1873) 296.
[303] Lib. xix. c. 26 (Littré’s translation).
[304] _Géographie Botanique_, ii. (1855) 655.
[305] Meyer, _Geschichte der Botanik_, iii. (1856) 531; also Schübeler
_l. c._; Pfeiffer, _Buch der Natur von Konrad von Megenberg_,
Stuttgart, 1861. 418.
[306] _Herball_, part 2. (1568) 111.
[307] _Dyetary of Helth_, Early English Text Society, 1870. 278.
[308] _Herball_, edited by Johnson, 1636, 240.
[309] _Adam in Eden, or Nature’s Paradise_, Lond. 1657. chap. 256.
A transverse section of the fresh root displays a large central column
with a radiate and concentric arrangement of its tissues, which are
separated by a small greyish circle from the bark, whose breadth is
from ½ to 2 lines. In the root branches there is neither a well-defined
liber nor a true pith. The short leaf-bearing branches include a large
pith surrounded by a circle of woody bundles. The bark adheres strongly
to the central portion, in which zones of annual growth are easily
perceptible, at least in older specimens.
=Microscopic Structure=—The corky layer is made up of small tabular
cells as usual in suberous coats. In the succeeding zone of the
middle bark, thick-walled yellow cells are scattered through the
parenchyme, chiefly at the boundary line of the corky layer. In the
root the cellular envelope is not strikingly separated from the
liber, whilst in its leafy branches this separation is well marked by
wedge-shaped liber bundles, which are accompanied by a group of the
yellow longitudinally-elongated stone-cells. The woody bundles contain
a few short yellow vessels, accompanied by bundles of prosenchymatous,
not properly woody cells. The centre, in the root, shows these woody
bundles to be separated by the medullary parenchyma; in the branches
the central column consists of an uniform pith without woody bundles,
the latter forming a circle close to the cambium. The parenchyma of the
whole root collected in spring is loaded with small starch granules.
=Chemical Composition=—Among the constituents of horse-radish root (the
chemical history of which is however far from perfect) the volatile
oil is the most interesting. The fresh root submitted to distillation
with water in a glass retort, yields about ½ per mille of oil which is
identical with that of Black Mustard as proved in 1843 by Hubatka. He
combined it with ammonia and obtained crystals of thiosinammine, the
composition of which agreed with the thiosinammine from mustard oil.
An alcoholic extract of the root is devoid of the odour of the oil, but
this is quickly evolved on addition of an emulsion of _White_ Mustard.
The essential oil does not therefore pre-exist, but only sinigrin
(myronate of potassium) and an albuminoid matter (myrosin) by whose
mutual reaction in the presence of water it is formed (p. 66). This
process does not go on in the growing root, perhaps because the two
principles in question are not contained in the same cells, or else
exist together in some condition that does not allow of their acting on
each other,—a state of things analogous to that occurring in the leaves
of _Lauro-cerasus_.
By exhausting the root with water either cold or hot, the sinigrin is
decomposed and a considerable proportion of bisulphate is found in the
concentrated decoction. Alcohol removes from the root some fatty matter
and sugar (Winckler 1849). Salts of iron do not alter thin slices of
it, tannic matters being absent. The presence of myrosin, which at
present has been inferred rather than proved, ought to be further
investigated. The root dried at 100° C afforded 11·15 per cent. of ash
to Mutschler (1878).
=Uses=—An infusion or a distilled spirit of horse-radish is reputed
stimulant, diaphoretic, and diuretic, but is not often employed.
=Substitute=—In India the root of _Moringa pterygosperma_ Gärtn. is
considered a substitute for horse-radish. It yields by distillation an
essential oil of disgusting odour which Broughton, who obtained it in
minute quantity, has assured us is not identical with that of mustard
or of garlic.