72. Musa sapientum, Linn.—Plantain; Banana.
Sex. Syst. Pentandria, Monogynia. [I have followed Roxburgh (Fl. Indica, vol. i.) in referring this genus to Pentandria, Monogynia. In Reichard's edition of Linnaeus's Systema Plantarum (1780), it is placed in Polygamia, Monogynia; and in Loudon's Encyclopaedia of Plants, it is referred to Hexandria, Monogynia.]
Plantains (Musa paradisiaca, Linn.) and Bananas (Musa sapientum, Linn.) are probably only varieties of the same species. The former have a stem wholly green, and persistent male flowers; the latter have a spotted stem, deciduous male flowers, and shorter and rounder fruit. Numerous varieties of each are cultivated in the tropical parts of Asia, Africa, and America; the wild parent is found at Chittagong, and other parts of tropical Asia. The fruit is a berry, and in the unripe state abounds in starch; but during maturation this disappears, being converted into a mucilaginous substance and this into sugar, so that in the ripe fruit not an atom of starch can be detected. [Avequin, Journ. de Pharm. t. xxiv. p. 555, 1838.]
Boussingault [Journ. de Pharmacie, xxii. 385.] analyzed the ripe fruit of Musa paradisiaca, and found in it sugar, gum, malic, gallic, and pectic acids, albumen, and lignin.
Plantains and bananas form important and valuable articles of food to the inhabitants of many tropical regions. "But for plantains," says Dr. Wright, [London Medical Journal, vol. viii.] "Jamaica would scarcely be habitable, as no species of provision could supply their place. Even flour, or bread itself, would be less agreeable and less able to support the laborious negro, so as to enable him to do him business, or to keep in health."
Humboldt [Humboldt's Pl. Aequinoc.; also, Library of Entertaining Knowledge—Vegetable Substances.] calculates that as 33 lbs. of wheat and 99 lbs. of potatoes require the same space as that in which 4,000 lbs. of bananas are grown, the produce of bananas is consequently to that of wheat as 133.1, and to that of potatoes as 44.1.
Dr. Shier, [Report on the Starch-producing Plants of the Colony of British Guiana, Demerara, 1847; also, Pharmaceutical Journal, vol. vii. p. 193, 1847.] in an interesting report on the starch-producing plants of British Guiana, has given us some interesting details respecting the plantain. He states that "a new plantain walk in this colony will yield 450 bunches of 50 lbs. each, of which, as nearly as possible, 50 per cent. will be core, containing 17 per cent. of starch, thus producing 17 cwt. of starch per acre." I am indebted to this gentleman for specimens of the sliced plantain core dried, plantain meal, and plantain starch, prepared in April 1847.
α. Sliced Plantain core.—The sample sent to me by Dr. Shier was prepared in April, 1847. It was obtained by stripping off the husk of the plantain, slicing the core, and drying it in the sun. The dried slices, as I have received them, are segments of circles from ½ to ¾ of an inch in diameter, and ⅛ to ⅙ of an inch in thickness. Their prevailing tint is whitish, like that of dried slices of Colchicum cormi, but marbled with reddish veins. Their odour is fragrant, and somewhat similar to that of orris root. Their taste is farinaceous.
β. Plantain meal; Conquin-tay.—Obtained by powdering and sifting the thoroughly dried sliced plantain core. It is known among the Creoles of the colony by the name of Conquin-tay. It is a whitish meal, speckled with minute dark-reddish spots. Its odour is fragrant, and similar to that of orris root (Dr. Shier says it resembles fresh hay or tea). Its taste is bland, like that of common wheat flour. When examined by the microscope, it is seen to consist chiefly of starch grains. According to Dr. Shier's statement, plantain meal contains about 68 per cent. of starch. 100.0 parts of plantain meal yielded Dr. Shier 0.88 parts of nitrogen. If this number be multiplied by 6.5 (see ante, p. 106, foot-note), we have 5.72 as the per centage amount of proteinaceous matter (albumen, gluten, &c.) contained in plantain meal.
It is obvious, therefore, that plantain meat must be greatly superior to the pure starches, inasmuch as it contains blood- and flesh-making principles which the latter are devoid of. Dr. Shier states that it is easy of digestion, and that it is largely employed in British Guiana as the food of infants, children, and invalids; but it will not serve for the manufacture of maccaroni, as this, when made from it, falls to powder when put into hot water. The same authority tells us that the plantain yields about 20 or 25 per cent. of meal.
γ. Plantain starch.—This is obtained from the plantain by rasping and washing; but owing to the flesh-coloured tissue in which the starch is imbedded being somewhat denser than the latter, it settles below the starch, and it is somewhat difficult to separate completely the finer parts of it from the starch; hence the latter is not perfectly white. The plantain yields about 17 per cent. of starch. Examined by the microscope, I find the starch grains [The following measurements, in parts of an English inch, of the particles of plantain starch (prepared by Dr. Shier, of Demerara) were kindly mads for me by Mr. George Jackson:—Particles. Length. Breadth. 1. 0.0020. 0.0013. 2. 0.0018. 0.0009. 3. 0.0016. 0.0010. 4*. 0.0014. 0.0007. 5*. 0.0013. 0.0008. 6. 0.0009. 0.0006. 7. 0.0007. 0.0005. 8. 0.0005. 0.0003. The most prevalent-sized particles are marked thus *.] to be flat, transparent disks, like those of the starch of Zingiberaceae; hence they have but little lateral shading, and when superimposed the contour of the lower grains can be seen through the upper ones. Their shape is more or less elliptical and ovate, the extremity at which the so-called nucleus or hilum is placed being narrower than the opposite one. When viewed edgewise, their shape appears to be linear, and the lateral shading is stronger.
The lines or segments of rings seen on the flat surfaces of the grains do not extend to the edges of the grain, nor do they surround the hilum. When examined by the polarizing microscope, these grains present the well-known crosses. In its chemical, dietetical, and medicinal properties, the starch of the plantains agrees with those of other starches.