ARROW-HEADED CHARACTERS. See CUNEIFORM. ARROW-HEADS. See ELF-ARROW-HEADS.
is a variety of starch extracted from the roots of certain plants grow ing in tropical countries. It is a fine starchy farina, much valued as a delicacy, and as an easily digestible food for children and invalids. It is obtained from the tuberous roots—or more correctly, the root-stocks (alazomes)—of different species of the genus maranta, belonging to the natural order marantacete, and characterized by solitary ovules, a fleshy style curved downwards, branching stems, and white flowers. The species chiefly yielding it is M. arundenacca, a native of tropical America, cultivated in the West India islands, and growing about 2 ft. high, with ovato-lanceolate some what hairy leaves, clusters of small flowers on 2-flowered stalks, and globular fruit about the size of currants. The roots (or rhizomes) contain a large proportion of farina. They are often more than a foot long, of the thickness of a finger,• jointed, and almost white, covered with pretty large paper-like scales. They sometimes curve so that the points rise out of the earth, and form new plants. They are dug up when a year old, washed, carefully peeled, and reduced to a milky pulp. Mills for this purpose have been introduced, but in Jamaica the roots are usually reduced by beating in deep wooden mortars; in Bermuda by means of a wheel-rasp. The pulp is then mixed with much water, cleared of fibers, by means of a sieve of coarse cloth or hair, and the starch is allowed to settle to the bottom. The water dissolves, and so removes the greater part of the albumen and salts, the starch quickly settling down as an insoluble powder. Successive washings are employed for further purification. The A. is finally dried in the sun or in drying-houses, great care being taken, by means of gauze, to exclude dust and insects. The careful peeling of the roots is of great importance, as the skin contains a resinous matter, which imparts a disagreeable flavor to A. with which it is allowed to mix. Great care is taken to preserve the A. from impurities; and the knives used in peeling the roots, and the shovels used in lifting the A., are made of German silver.
The West Indian A., most esteemed in the market, is grown in Bermuda; the next, and almost equal to it, iu Jamaica. The East Indian A. is not in general so highly valued, perhaps because substitutes for the genuine A. more frequently receive that name. The maranta arundinacea is now, however, cultivated to some extent both in the East Indies and in Africa. .3f. indic,a, which was supposed to be distinct from Id. arundinacea, is now regarded as a mere variety of it, with perfectly smooth leaves. It is cultivated both in the East Indies and in Jamaica. A. is obtained also from 3f. allouyia and At nobili$ in the West Indies, and from M. /Timm:min/a in the East.
The amount of fecula or starch present in the roots of the maranta varies according to age, and runs from 8 per cent, in those of the young plant, to 26 per cent when full grown. The latter stage is reached when the plant is 10 to 12 months old; and the roots then present the following composition in 100 parts: Starch, fecula, or arrow-root Woody fiber . . 6 Albumen .. .
Gummy extract, volatile oil, and salts............. 1 Water. 654 A is exported in tin eases, barrels, or boxes, carefully closed up. It is a light, opaque, white powder, which, when rubbed between the fingers, produces a slight crackling noise, like that heard when newly fallen snow is being made into a snow-ball. Through the microscope, the particles are seen to be convex, more or less elliptical, sometimes obscurely triangular, and not very different in size. The dry farina is quite iuodorous, but when dissolved in boiling water it has a slight peculiar smell, and swells up into a very perfect jelly. Potato-starch, with which it is often adulterated, may be distin guished by the greater size of its particles, their coarser and more distinct rings, and their more glistening appearance. Refined sago-flour is used for adulteration, many of the particles of which have a truncated extremity, and their surface is irregular or tuber culated. A. is also sometimes adulterated with rice-starch and with the common starch of wheat-flow.