Related entries: Amylum (U. S. P.)—Starch
The prepared farina from the pith of the Metroxylon Rumphii, Martius (Sagus Rumphii, Willdenow; Sagus genuina, Blume), and other species of palm.
Botanical Source.—Metroxylon Rumphii, or Sago palm, has an erect stem, of middling height, with large, pinnately-divided leaves, and prickly petioles, rachides, and spathes; the prickles scattered or confluent. The flowers are polygamomonoecious, on the same spadix. The spadix is much branched, and sheathed by many incomplete spathes. The amenta are terete; the calyx 3-cleft; the corolla tri-partite. Stamens 6, with anthers affixed by the back. The fruit is a 1-seeded, globose berry, coated by reversed scales, and depressed on both sides.
History and Preparation.—This tree is common to New Guinea and the Molucca Islands, growing spontaneously in low, swampy lands, and the sago is obtained from its pith, or spongy medullary substance, of which it contains a large quantity when the tree is sufficiently developed. Several species of palm are known to produce fine sago, among which may be named Metroxylon Sagu, Rottboell (Sagus laevus, Blume; Metroxylon Sago, Koenig; Metroxylon laeve, Martius; Sagus inermis), which is the Spineless or Unarmed sago palm, a native of Borneo and Sumatra; the Arenga saccharifera, Labillardière (Saguerus Rumphii, Roxburgh), the sugar palm, abounding in all the isles of the Indian Ocean; and the Sagus farinifera, Lamarck, and other palms.
As soon as the palm has arrived at a sufficient degree of maturity, which is from 5 to 7 years, it is cut into pieces of 5 or 6 feet in length; the woody part is cut off on one side, exposing the pith lying, as it were, in the hollow of a canoe. Cold water is poured in, and the pith well stirred, by which means the starch is separated from the fibrous part and passes through with the water, when the whole is thrown on a sieve. The sago, thus separated, is allowed to settle; the water is poured off, and, when it is half dry, it is granulated by being forced through a kind of funnel. It is then either air-dried (sago flour), or it is granulated by mechanical means, and dried by artificial heat, which causes part of the starch to become gelatinous (pearl sago). A single tree of some species, will yield no less than from 200 to 500 pounds. (For an interesting description of the cultivation of sago in north Borneo, see Amer. Jour. Pharm., 1895, p. 331.)
Description and Chemical Composition.—Sago occurs in commerce either in the form of a fine amylaceous powder, called sago meal or sago flour, or as pearl sago. Sago meal is whitish, with a reddish tint, of a feeble, somewhat unpleasant, moldy odor, and has the general characters of starch. The microscope shows it to consist of irregularly elliptical or oval, more or less ovate, usually isolated particles, often narrowed or tapered at one extremity, and appearing as if truncated, or more or less mullar-shaped; most of them have an irregular surface as if eroded (see illustration of sago-starch grains, in Amer. Jour. Pharm., 1876, p. 297). Pearl sago occurs in white or brownish, pearl-like grains, which vary in size from that of a poppy seed to that of a white mustard seed, or even larger. It is the kind usually met with in commerce, and contains about 86 per cent of starch, 13 per cent of water, and small amounts of mineral and nitrogenous matters. A factitious sago is frequently prepared from potato starch.
Action, Medical Uses, and Dosage.—Sago is nutritive and demulcent, and is a convenient and agreeable article for making puddings, gruel, and diet drinks for the sick-room. It should always be long boiled before it is used. It is not so much used as formerly, being superseded by the purer arrow-root and tapioca. For common uses, half an ounce of sago may be boiled in a pint of water (in some cases milk is preferred), the solution strained, and flavored with sugar and spices, lemon, or even with a little white wine, when there are no contraindications to their use.
CASTILLON'S POWDERS, a popular article of diet for invalids, in cases of indigestion, chronic dysentery, etc., is composed of sago, salep, tragacanth, each, in powder, 4 drachms; powdered prepared oyster shells, 1 drachm. These are to be well mixed, and divided into 12 powders; sometimes it is colored with a small quantity of cochineal. For use, each powder is to be boiled with a pint of milk, which may be sweetened and flavored to suit the patient's taste.