135. Manihot utilissima, Pohl.—Bitter Cassava.
[Plant. Brasil. Icones et Descript., fol. Vindob. 1827-31.]Sex. Syst. Monoecia, Monadelphia.
(Fecula of the root; Tapioca, E. D. [U. S.])
Synonymes.—Jatropha Manihot, Linn.; Janipha Manihot, HBK. ii. 85; Hooker, Bot. Mag. t. 3071.
History.—Monardes [Clusii Exoticor. lib. x. cap. 53>, 330.] describes the Indian method of making cassava bread; and Piso [De Medicina Brasil, p. 52.] notices the mode of preparing the farina called cream of Tipioca [Tapioca].
Botany. Gen. Char.—Flores monoecious. Calyx corolline, campanulate, 5-cleft, convolute. Corolla 0. Stamens 10, inserted on the margin of a fleshy disk, free, the alternate ones shorter: filaments filiform; anthers turned inwards, 2-celled. Ovary placed on the fleshy disk, 3-celled, with 1 ovule in each cell. Style short. Stigmas 3, many-lobed, the lobes consolidated into a conical sinuated-sulcated mass. Capsule 3-coccous; the cocci 2-valved and 1-seeded (Endlicher).
Sp. Char.—Leaves with very long petioles, deeply 7-parted, palmate; the segments lanceolate, acuminate, attenuated at the base, quite entire, the outer ones smaller, unequal, diverging, straggling. Root whitish-yellow (Pohl).
Root large, thick, tuberous, fleshy; containing an acrid, milky, highly poisonous juice. Flowers axillary, racemose. [Hooker, Bot. Mag. t. 3071.]
Hab.—Native of the Brazils; where, as well as in other parts of South America, it is cultivated.
Manihot Aipi, Pohl.—Sweet Cassava, Bancroft, Nat. Hist, of Guiana, 1769.—This is usually regarded as a variety of the above; but Pohl considers it to be a distinct species; characterized by the leaves which are 5-parted, and by the root, which is reddish, and contains a milky non-poisonous juice. It is cultivated in the Brazils, and in Spanish America.
Manihot Janipha, Pohl; Jatropha Janipha, Linn.; Janipha Loeflingii, HBK.—This species is said to yield the sweet or white cassava of the West Indies. Dr. Hamilton [Hamilton, Pharmaceutical Journal, vol. v. p. 27, 1845.] says it so closely resembles the Janipha Manihot, Linn. (Manihot utilissima, Pohl), that an experienced eye can hardly distinguish it with certainty. Is not the sweet cassava of the West Indies the Manihot Aipi of Pohl? Like the latter, it is devoid of poisonous properties.
Description.—1. Bitter cassava root is a large tuberous root [A figure of the root it given in the Journ. de Pharm, t. xxii. 1836.] which abounds in a poisonous milky juice. It is difficult to distinguish by its appearance from the sweet cassava root; but it is devoid of the tough, fibrous, or woody filaments found in the heart of the sweet cassava root; and it does not become soft, like the latter root, by boiling or roasting. The rasped root mixed with water, boiled, and then fermented, yields a spirituous liquor called cassiri. [Dr. Hamilton, Pharmaceutical Journal, vol. v. p. 29, 1849.] Cassava meal is obtained by subjecting the grated root to pressure to express the juice, and then drying and pounding the residual cake. Of this meal cassava bread is made. The expressed juice by repose deposits the farina called cassava starch, of which tapioca is made. A sauce called casareep or cassireepe, is made from the juice. [Casareep is the concentrated Juice of the root of the bitter cassava flavoured by aromatics. During the evaporation, the poisonous principle of the juice it either dissipated or destroyed. Casareep is used to flavour soups and other dishes; and is the basis of the West Indian dish pepper-pot. It is a powerful antiseptic (Shier, Report on the Starch-producing Plants of the Colony of British Guiana, Demerara, 1847; Hamilton, Pharmaceutical Journal, vol. v. p. 30, 1845).—In French Guiana, the term cabiou or cabion is applied to a similar condiment (Henry and Boutron-Chalard, Journ. de Pharm, t. xxii. p. 123). The inspissated juice flavoured with capsicum pods is used in the Brazils as a sauce, under the name of Tycupi or Tucupi (Martius, Syst. Mat. Med. Veg. Brasil, p. 94).]
2. Sweet cassava root resembles the bitter cassava root in external appearance; but, unlike the latter, it is not poisonous. It has a bundle of tough, fibrous, or woody filaments at the heart, running longitudinally through the root. By boiling or roasting it becomes soft, and is used at table.
A few pounds of dried sweet cassava root have recently been sent to England from Jamaica on speculation, to ascertain whether it was likely to prove a profitable article of commerce. It consisted of transverse and longitudinal segments, which were beautifully white, had a very faint agreeable odour, and were mucilaginous or farinaceous to the taste. The circular disks were from one to two or more inches in diameter, and had in the centre the ligneous cord above alluded to. Some of the pieces were worm-eaten: a few were slightly scorched or burnt, apparently by over-heating in the drying process.
Cassava meal and bread, cassava starch, and tapioca, are prepared from the sweet as well as from the bitter cassava root.
Composition.—The bitter cassava root has been analyzed by MM. 0. Henry and Boutron-Chalard, [Journ de Pharm, t. xxii. p. 118, 1836.] who inferred that it contained free hydrocyanic acid, starch, a small quantity of sugar, an organic salt of magnesia, a bitter principle, a crystallizable fatty matter, an azotized matter (vegetable osmazome), phosphate of lime, and woody fibre.
1. Hydrocyanic Acid.—According to O. Henry and Boutron-Chalard, the active principle of the root is hydrocyanic acid. Their statement is confirmed by Dr. Christison, who examined some well-preserved juice from Demerara.
2. Volatile Acrid Principle?—The vomiting and purging, and other abdominal symptoms ascribed to bitter cassava, would lead us to suspect that, like other euphorbiaceous plants, it contains an acrid principle.
Physiological Effects.—The fresh roots as well as the expressed juice are virulent poisons, destroying life in a very short period of lime. 0. Henry and Boutron-Chalard described the effects on guinea-pigs as resembling those caused by hydrocyanic acid; but death did not occur until from forty to fifty-five minutes after the use of the poison. Ricord Madianna [Quoted by Sloane, Jamaica, vol. ii. p. 363.] has killed dogs in ten minutes with a poison obtained from this root. The symptoms described by Barham [Hortus Americanus, p. 34, 1794.] are pain and swelling of the abdomen, vomiting and purging, dimness of sight, syncope, rapid diminution of the powers of life, and death in a few hours. Half a pint of the juice has produced death in an hour. [Journ. de Pharm, t. xvi. p. 310, 1830.]
Uses.—Dr. Wright [Med. Plants of Jamaica.] says that the scrapings of the fresh root are successfully applied to ill-disposed ulcers; and Dr. Hamilton [Martius, in Wibmer, Arzneim. u. Gifte, Bd. iii. S. 273.] speaks of the instantaneous relief which he experienced on himself from the application of a cataplasm of the rasped roots, with all their juices unexpressed, to the spot where a nest of chigres (Pulex penetrans) had been dislodged. The root is used to catch birds, which, by eating it, lose the power of flying. [Pharmaceutical Journal, vol. v. p. 28, 1848.] It yields cassava meal and cassava starch.
1. Farina Mandiocae; Cassava or Cassada Meal; Farinha de Pao, or simply Farinha; Farine de Manioc.—This is obtained by washing and scraping the roots, then rasping or grating them, and subjecting the pulp to pressure, by which the poisonous juice is expressed. The residual compressed pulp is then dried over a fire, being stirred during the whole time. In this way is obtained cassava meal. [The details of the process for making cassava meal vary somewhat in different localities. According to Piso (De Medicina Brasil, lib. iv. p. 53), the roots are grated by a handmill somewhat similar to that used in the preparation of Tous-les-Mois (see ante, p. 228, Fig. 224). Edwards (Voyage up the River Amazon, p. 24, Lond. 1847) says they are grated upon stones, and the pulp compressed in a slender bag of rattan six feet in length.]
Cassava meal is a mixture of cassava starch, vegetable fibre, and proteine or albuminous matters. Dr. Shier [Report, p. 15.] found that in the sliced and dry roots the percentage of nitrogen is 0.78, but in the cassava meal (the juice expressed) only 0.36. If these numbers be multiplied by 6.5 (see foot-note at p. 106), the percentage quantity of protein or albuminous matters in the dried root will be 5.0, and in cassava meal 2.34.
I have received from Dr. Shier two kinds of cassava meal; one called cassava meal, the other termed cassava flour. I shall distinguish them as coarse and fine meal.
α. Coarse Cassava Meal; Cassava Meal, Shier; Couaque or Couac, Guibourt.—This is meal which in coarseness is about equal to sawdust or small dried crumbs of bread. I have found a similar preparation in English commerce under the name of "Tapioca Flour from Bahia".
Coarse cassava meal has a slight yellowish or brownish tint, varying in different samples.
β. Fine Cassava Meal; Cassava Flour, Shier; Farine de Manioc, Guibourt.—This is a finer and whiter meal than the preceding. In fineness it resembles wheat flour.
Cassava bread or cassava cakes are made by baking the compressed cassava pulp on a hot plate, in the manner muffins and crumpets are baked in England.
Cassava meal and cassava bread are important and valuable articles of food to the inhabitants of tropical America. The flavour of cassava cakes reminds me of Scotch oatcakes.
2. Amylum Mandiocae; Mandioca or Cassava Starch; Tapioca.—The juice which is expressed from the rasped root deposits on standing an amylum or starch (cassava starch), of which tapioca is made.
α. Cassava Starch; Tapioca Meal; Brazilian Arrow-root; Moussache or Cipipa.—The fecula or starch deposited from the expressed juice of the cassava root, after being washed and dried in the air without heat, constitutes the tapioca meal or Brazilian arrow-root of commerce. It is usually imported into this country from Rio Janeiro. For some years past it has been imported into France from Martinique, and is sold as arrow-root (Guibourt). It is white and pulverulent, and resembles in external appearance genuine arrow-root (maranta starch). When examined by the microscope, however, it is readily distinguished.
Cassava starch, when examined by the microscope, is found to consist of small single grains, [The following are the measurements, in parts of an English inch, of ten grains of cassava starch. They were made by Mr. George Jackson: 1. Length 0.0012, Breadth 0.0012. 2. 0.0008 x 0.0008. 3. 0.0008 x 0.0007. 4. 0.0007 x 0.0006. 5. 0.0005 x 0.0004. 6. 0.0005 x 0.0004. 7. 0.0004 x 0.0004. 8. 0.0003 x 0.0003. 9. 0.00025 x 0.00025. 10. 0.0002 x 0.0002.] which, in the living plant, were united in groups or compound grains, each composed of 2, 3, or 4 grains. Most of the grains are mullar-shaped, and, therefore, have been united in groups of two each: when seen endwise, they appear circular or globular. Some of them are truncated egg-shaped grains, with one or two facets at the truncation. The nucleus, central cavity, or hilum, is circular, surrounded with rings, and bursts in a stellate manner.
These statements apply equally to bitter cassava starch and sweet cassava starch sent to me from Demerara by Dr. Shier, as well as to starch obtained by myself from sweet cassava root received from Jamaica.
Cassava starch has not been analyzed; but there can be no doubt but that its composition is similar to that of other starches, and that its formula is C12H10O10. Its effects and uses are also like those of other starches (see ante, p. 119).
β. Tapioca.—This is imported from Bahia and Rio Janeiro. It is cassava meal, which while moist or damp has been heated, for the purpose of drying it, on hot plates. By this treatment the starch grains swell, many of them burst, and the whole agglomerate in small irregular masses or lumps. In consequence of the change thus effected in the starch grains, tapioca is partially soluble in cold water; and the filtered cold infusion strikes a blue colour with tincture of iodine. The drying to which it has been subjected renders it difficult of solution. In boiling water it swells up, and forms a transparent viscous jelly-like mass. Submitted to prolonged ebullition in a large quantity of water, it leaves an insoluble residue, which precipitates. This, when diluted with water and coloured by iodine, appears to consist of mucous flocks.
Made into puddings, tapioca is employed as a dietetical substance. Boiled in water or milk, and flavoured with sugar, spices, or wine, according to circumstances, it is used as an agreeable, nutritious, light, easily digestible article of food for the sick and convalescent. It is devoid of all irritating and stimulating properties.