32. Oryza sativa, Linn.—Common Rice.
Tribe I. Oryzeae, Endl.
Synonymes.—Oρυζον, Theophr. Hist. Plant., lib. iv. cap. 5; ορυζα, Dioscor., lib. ii. cap. 117; Galen, de simpl. med. facult., lib. viii. cap. xv. 16; Oryza, Pliny, Hist. Nat., lib. xviii. cap. 13.
Botany.—Stems numerous, 2 to 8 or 10 feet long. Leaves long and slender. Panicle diffuse thin, bowing when the seed is weigthy. Spikelet hermaphrodite, 1-flowered; glumes 2, small; paleae 2; scales 2, smooth; stamens 6; ovary sessile; styles 2; stigma feathery. Caryopsis compressed, enclosed by the paleae.—Originally a native of Asia. Extensively cultivated in India, China, the Indian Archipelago, and most other Eastern countries; in the West Indies, Central America, and the United States; and in some of the Southern countries of Europe. Forty or fifty varieties [Roxburgh, Flora Indica, vol. ii. p. 200, 1822.] are known to and cultivated by the Indian farmers; of these some are awned—others are awnless. The kinds most esteemed in this country are the Carolina and Patna rice. Patna rice is imported in bags holding 1 ½ cwts. each. It has usually been mixed with lime, to prevent the attack of insects. The grain, whilst enclosed in the paleae or husk, is called paddy (padi or paddie) by the Malays, bras when deprived of the husk, and nasi after it has been boiled.
Composition.—Rice has been analyzed by Vauquelin [Mém. du Museum d'Hist. Nat. t. iii. p. 229, 1817.], by Braconnot [Ann. Chim. Phys. t. iv. p. 383, 1818.], by Vogel [Quoted by L. Gmelin, Handb. d. Chemie, Bd. ii. S. 1345.], and by d'Arcet and Payen [Journ. de Chimie Méd. t. ix. p. 221, 1833.] (see ante, p. 106). The composition of Carolina and Piedmond rice is, according to Braconnot, as follows:—
||Carolina Rice.||Piedmont Rice.|
|Parenchyma (woody fibre)||4.80||4.80|
|Rancid, colourless, tallowy oil||0.13||0.25|
|Phosphate of lime||0.40||0.40|
|Acetic acid, phosphate of potash, chloride of potassium, and vegetable salts of potash and lime.||traces.||traces.|
The inorganic constituents of rice have been before stated (see ante, p. 106).
1. Rice starch is manufactured, under Mr. Orlando Jones's patent, as follows: Patna rice is first freed from stones, dust, &c., by a process analogous to winnowing, and is then digested whole in a solution of caustic soda containing 200 grains of soda to the gallon. The solution being poured off, the grain, which has thus been deprived of part of its gluten, is ground in a mill, and the ground rice mixed with a solution of the same strength, so as to form a mixture having the consistence of thick cream. More lye is then added, and the mixture stirred up for a few hours, and then left to deposit: a heavy matter, called fibre (heavy starch), deposits, while the starch (lighter starch) remains suspended. The liquor is then run off into shallow vessels, where the starch deposits: the alkaline solution of gluten is then drawn off, and the starch repeatedly washed with water and then allowed to deposit. The starch mass is now obtained of the consistence of clay. It is then usually mixed with blue colouring matter (smalt), to fit it for the use of the laundress, and removed to draining-boxes, which are lined with cloth. These consist each of two cells, whose size is 3 feet long, 6 inches deep, and 6 inches broad. Here the starch forms a lump or mass of the shape and size of the cell, and is afterwards cut into 6 cubical blocks, which are placed on chalk-stones to drain, and are then partially dried in a stove, to produce what is called crusting. The crust is scraped off, the block wrapped in paper and returned to the stove to dry, when it splits into the columnar masses commonly known as the race of the starch. If, instead of crusting the lumps, the starch were slowly dried, decomposition is apt to take place; and, if rapidly dried, the races are apt to be small and needle like. 100 lbs. of Patna rice, as it occurs in the market, yield from 80 to 85 lbs. of good marketable starch, 7.5 lbs. of fibre, the remainder being gluten, gruff or bran, and a small quantity of light starch, carried off in suspension in the alkaline liquor.
Vogel states that, from dried rice, he obtained 96 per cent, of starch.
When examined by the microscope, the granules are observed to be polygonal, and very minute; their average diameter being about 1/5263d part of an inch [The following are the measurements of the particles of rice starch made by my friend Mr. Jackson:—1: .00027 Inches. 2. .00021. 3. .0002. 4. .00017. 5. .0001. 5) .00095 / .00019 = 1/5263. Most of the particles are angular; but the measurements were taken on those which most nearly approached the globular form.]. They are the smallest granules of all the commercial starches. According to Vauquelin, rice starch begins to dissolve in water at from 122° to 132° F.
Two kinds of rice starch are found in the shops: one, prepared under Orlando Jones's patent; the other, called Mechlin glaze starch, manufactured by Mottram, Rebè & Co.
2. Proteine matters. Rice contains a much smaller proportion of the so-called gluten than wheat does. According to Horsford [Ann. Chem. u. Pharm. Bd. xlviii. 1846.] and Payen (see ante, p. 106, and vol. i. p. 119), the quantity is about 7 per cent.
The substance which the rice starch-makers term gluten is analogous to what Mulder calls proteine, being obtained by carefully neutralizing the alkaline solution in which rice has been digested with an acid, by which a precipitate forms, which, when separated from the supernatant liquor, has a creamy consistence, an agreeable smell, and a bland taste, like pap. By evaporation, it forms a dark-coloured hard mass. If kept for some time in the moist state, it undergoes decomposition, and evolves an odour somewhat like sour yeast. Mixed with eggs, I have employed it, in the form of a baked pudding, in diabetes.
3. Fatty matters.—The quantity of fatty matter contained in rice is smaller than in other varieties of corn. The outer part of the grain appears to contain more than the inner part.
Effects.—Rice, though nutritious, is less so than wheat: this is proved by chemical analysis, which shows the much smaller proportion of glutinous or nitrogenous matter found in the former than in the latter grain (see ante, p. 106, and vol. i. p. 119). "Rice," says Boussingault [Ann. Chim. et Phys. lxvii. p. 413.], "is held up as a most nutritive food; but though I have lived long in countries which produce it, I am far from considering it as a substantial nourishment. I have always seen it, in ordinary use, replace bread; and when it has not been associated with meat, it has been employed with milk."
The solid or dry part of rice does not materially differ from the solid or dry part of potatoes in the proportion of starch and gluten which it contains; and, therefore, as far as regards these principles, the nutritive values of anhydrous rice and anhydrous potatoes are about equal. But, in some Union poor-houses, the substitution of an equal weight of boiled rice for potatoes was followed in a few months by scurvy [Provincial Medical and Surgical Journal, June, 1847. Dr. Garrod (Monthly Journal of Medical Science, January, 1848) calculates that, prior to the substitution, the usual weekly food of the men in the Crediton Union contained 186 grains, and of the women 181 grains of potash; but, after the substitution, the weekly amount of potash taken by the men was about 51 grains, and by the women 46 grains, or a reduction of more than two thirds: and he ascribes the occurrence of scurvy after the use of rice to the inferior proportion of potash which this grain contains in comparison with potatoes. We ought, however, also to take into consideration the fact that rice is deficient in certain vegetable acids found in the potato (see ante, p. 107). (Looks like they didn't know, back then, that scurvy is a deficiency of vitamin C (= ascorbic acid). -Henriette)].
Rice, when swallowed in the raw state, swells up in the alimentary canal, and acts injuriously by the mechanical distension it gives rise to. Mr. Hovell [Lancet, April 10th, 1847, p. 390.] has reported a case in which great pain, peritoneal inilammation, and death, arose from the ingestion of a tumblerful of raw rice.
"Rice," says Marsden [History of Sumatra, p. 65, 3d ed. 1811.], "is the grand material of food, on which a hundred million of the inhabitants of the earth subsist, and although chiefly confined by nature to the regions included between, and bordering on the tropics, its cultivation is probably more extensive than that of wheat, which the Europeans are wont to consider as the universal staff of life."
Rice is less laxative than the other cereal grains. Indeed, it is generally believed to possess a binding or constipating quality: and, in consequence, is frequently prescribed by medical men as a light, digestible, uninjurious article of food in diarrhoea and dysentery.
Various ill effects, such as disordered vision, &c., have been ascribed to its use [Bontius, Account of the Diseases, Natural History, &c., of the East Indies, translated into English, 1769; also, Bricheteau in Tortuelle's Elem. d. Hygiène, 4me éd.]; but, as I believe, unjustly so. Neither does there appear to me to be any real foundation for the assertions of Dr. Tytler [Lancet, 1833-34, vol. i.], that malignant cholera (which he calls the morbus oryzeus, or rice disease) is induced by it.
Uses.—Rice is employed as a nutriment in a variety of forms; e. g. boiled rice, rice milk, rice pudding, rice cakes, &c. In China, rice vermicelli is prepared from it. This is sold in flat bundles (of about 5 inches long, and 1 ¼ inch broad), composed of a folded thread or filament made of rice paste. Medicinally, rice is employed as a demulcent, somewhat binding, nutritive substance in diarrhoea, &c. Gardiner's alimentary preparation is very finely ground rice meal.