The sifted flour of the grain of Triticum sativum, Lamarck (Triticum vulgare, Villars).
COMMON NAMES: Common flour, Wheat flour.
ILLUSTRATION (of plant): Bentley and Trimen, Med. Plants, 294.
Botanical Source.—This plant, the common winter wheat, described as Triticum sativum, var. hybernum, has a fibrous root, and a round, smooth, straight stem, 3 to 4 feet or more in height, the internodes being somewhat inflated. The leaves are lance-linear, veined, roughish above, with truncate and bristly stipules. The flowers are borne on a 4-cornered, imbricated, terminal spike, 2 or 3 inches in length, with a tough rachis. The spikelets are crowded, broad-ovate, about 4-flowered; the glumes ventricose, ovate, truncate, mucronate, compressed below the apex, round and convex at the back, with a prominent nervure. The paleae of the upper florets are somewhat bearded. The grains are loose (W.—L.—Wi.).
History.—Several species of Triticum are cultivated in different countries, among which may be named the Triticum sativum (Triticum vulgare), the species most generally raised in this country and Europe. It has two varieties, Triticum aestivum, or spring wheat, and Triticum hybernum, or winter wheat. Linnaeus considered these as distinct species, but botanists of the present day generally refer them to one common stock. Barley and oats have the perianth attached to the grain, which is not the case with wheat. Wheat is supposed to be a native of Central Asia, in the country of the Baschkirs. The medicinal part is the seeds, deprived of their husk, and ground to a fine flour. Wheat is subject to ravages from several parasitical fungi, viz.: (1) Bunt, smut-balls, or pepper-brand, produced by Uredo Caries, and giving a disgusting odor to the flour. This fungous plant is also called Tilletia Caries, and infests corn grains and other grasses. (2) Smut, dust-brand, or burnt-ear, produced by Ustilago segetum (Uredo segetum, Ustilago carbo). (3) Rust, red-rag, red-robin, or red-gum, caused by the young state of Puccinia graminis. (4) Mildew, produced by the more advanced growth of P. graminis. (5) Ergot, caused by the Claviceps purpurea, and which is as powerful in its action on the uterus as ergot of rye. Two diseases of wheat are produced by parasitical animalcules, viz.: (1) Ear-cockle, purples, or peppercorn, caused by a microscopic, eel-shaped, animalcule, called Vibrio tritici, or Anguillula tritici. (2) Wheat midge, an abortion of the grains caused by a minute, 2-winged fly called Cecidomyia tritici (P.).
Description and Chemical Composition.—Flour is the finely sifted, amylaceous constituent of the wheat; the broken, integumentary structures constitute bran. Good wheat flour is very white, has a faint, peculiar odor, and is nearly tasteless. One hundred parts of air-dry wheat contain, on an average, 13.37 per cent moisture, 12.04 per cent gluten and other nitrogenous matter, 1.91 per cent fatty matter, 69.07 per cent starch, gum, dextrin, and sugar, 1.9 per cent crude fiber, and 1.71 per cent ash. These figures, recorded by J. König (Nahrungs- und Genussmittel, 3d ed., 1893), represent the average of 1358 analyses of wheat from all parts of the globe. The ash consists of silica, and phosphates of potassium, calcium, magnesium, and sodium, these bases also occurring as sulphates and chlorides. According to the same authority, the composition of wheat-bran is subject to great variation, and the average of 166 analyses is as follows: 15.66 per cent moisture, 14.61 per cent nitrogenous matter, 3.9 per cent fat, 53.6 nitrogen-free extractive matter (starch), etc., 6.7 per cent crude fiber, and 4.94 per cent ash. Richardson and Crampton (1886) found allantoin ½ per cent, a quickly drying oil, wax, cane sugar, and a sugar possessing strongly dextrogyre properties. The proportion of these constituents in wheat grains varies according to climate, soil, mode of culture, quality of manure, time of cutting, etc. The starch, which constitutes at least one-half of wheat grains is of finer quality, and of greater density than that from most other sources (see Amylum). The nitrogenous or protein matter of wheat consists of small amounts of vegetable albumin (about 1.6 per cent), and predominant amounts of the proteids of gluten, viz.: Gluten casein (Liebig's vegetable fibrin), insoluble in alcohol, and gluten fibrin, gliadin (glutin or vegetable gelatin) and mucedin, the latter three being soluble in alcohol of about 80 per cent strength (Ritthausen). The gluten of wheat is usually assumed as the most perfect form of that principle, and is more abundant in wheat than any other grain, rendering wheat flour superior in the manufacture of bread. It is through the presence of gluten that flour can be made into bread. The added quantity of yeast causes vinous fermentation, with evolution of carbonic acid gas, which expands the gluten into vesicles, and gives to the baked bread its spongy character. If wheat flour be kneaded into a paste with a little water, it forms a tenacious, elastic, soft, ductile mass. This is to be washed cautiously, by kneading it under a small stream of water till the water no longer carries off any starch, and runs off colorless; gluten remains. It is of a gray color, exceedingly tenacious, ductile, and elastic, has a peculiar smell, and is nearly tasteless. On exposure to the air it slowly dries, forming a hard, brittle, slightly transparent, dark-brown substance, resembling glue, which breaks like glass, with a vitreous fracture, imbibes water, but loses its tenacity and elasticity by boiling. It decomposes rapidly in a moist atmosphere, emitting a very offensive odor. Gluten casein in its reactions exhibits some resemblance to the casein of milk. It is insoluble in pure water, soluble in alkaline water, and precipitated from this solution by acids. It is separated from the gluten of the wheat by treatment with successive portions of alcohol of definite strength, in which it is insoluble. Gluten fibrin, mucedin, and gliadin, the constituents of gluten proper, are soluble in alcohol of 60 to 80 per cent, their separation being effected by their difference in solubility in water. Gliadin or vegetable gelatin is the constituent that imparts to the gluten its cohesive qualities.
As regards the wheat flour of the markets, we prefer flour ground in the stone mill, bolted in the old style, rather than the white starch flour known as patent process flour. A more recent view of the composition of gluten is that adopted by Osborne as recorded by Dr. H. W. Wiley (Principles and Practice of Agricultural Analysis, 1897, Vol. III, p. 436), from which the following is an abstract: "The gluten of wheat is composed of two proteid bodies, gliadin and glutenin. Gliadin contains 17.66 per cent, and glutenin 17.49 per cent of nitrogen. Gliadin forms a sticky mass when mixed with water, and is prevented from passing into solution by the small amount of mineral salts in the flour. It serves to bind together the other ingredients of the flour, thus rendering the dough tough and coherent. Glutenin serves to fix the gliadin, and thus to make it firm and solid. Glutenin alone can not yield gluten in the absence of gliadin, nor gliadin without the help of glutenin. Soluble metallic salts are also necessary to the formation of gluten, and act by preventing the solution of the gliadin in water, during the process of washing out the starch. No fermentation takes place in the formation of gluten from the ingredients named. The gluten which is obtained in an impure state by the process above described, is therefore not to be regarded as existing as such in the wheat kernel or flour made therefrom, but to arise by a union of its elements by the action of water."
The milky liquid produced by washing wheat flour, as above named, contains in solution gum, sugar, and vegetable albumen. Vegetable albumen may be obtained by allowing this fluid to deposit its starch, pouring off the supernatant liquor, and heating it to 60° to 71.1° C. (140° to 160° F.); flakes of coagulated albumen are formed. Vegetable albumen is soluble in water, but when coagulated by heat it is insoluble; it is also insoluble in alcohol and ether. When dry it is opaque, white, gray, brown, or black, according to circumstances, and is not adhesive like gum. Solutions of alkalies readily dissolve it. Vegetable albumen possesses nearly all the characters of animal albumen, and is considered identical in composition with it.
Wheat is now much subject to adulteration in this country by the wholesale admixture of white corn flour; the most we have to fear, however, is diseased wheat; but an examination under the microscope will at once detect parasitical growths, or their spores, etc.
Action and Medical Uses.—Wheat is very nutritive when made into bread or cakes and baked. Toasted bread, infused in water, forms an agreeable and lightly nourishing drink for invalids, especially those suffering from febrile or inflammatory attacks. It may be sweetened with loaf sugar, or a little molasses, and flavored, if desired, with strawberry juice, raspberry juice, lemon juice, etc., or the syrups of these fruits may be added to flavor it. Wheat flour is occasionally used to lessen the itching and burning sensations produced by urticaria, scalds, burns, erysipelas, etc.; rye-flour, however, is considered to act more efficiently. It is to be dusted upon the affected parts. It cools the part, excludes the air, and absorbs any discharges present, forming with them a crust which effectually protects the part underneath. When bread is soaked in milk, boiling hot, it forms the emollient bread and milk poultice; a small quantity of sweet lard or olive oil added improves it; yeast, with or without charcoal, mixed with this, forms an excellent antiseptic poultice; or, if powdered mustard be added, a sinapism is formed. When a bread poultice is applied to inflamed parts, the addition of a solution of borax will frequently facilitate its action. When it is desired to administer very small doses of remedial agents, this may be accomplished by mixing them with the crumb of bread (mica panis) in pill form. But nitrate of silver, if used thus, will be converted into a chloride, by the reaction ensuing between it and the salt in the bread. Wheat flour lightly baked, so as to acquire a pale buff tint, forms an excellent food for infants, invalids, and convalescents. It may be boiled with milk or milk and water, and lightly salted or sweetened as desired.
A very useful article of diet for patients, suitable in nearly all chronic affections has been recommended by Dr. T. J. Wright, of Cincinnati: The seeds of wheat are to be well cleansed by several washings in cold water, saving only those which sink to the bottom. Cover these with water, allow them to stand for 12 or 15 hours, then pour off the water, add some more, and boil for 2 or 4 hours, or until the spermoderm is cracked, then remove the wheat from the water. When cold it is ready for use. Small quantities only should be prepared at a time, especially in warm weather. This may be eaten with molasses, or sugar, the same as with boiled rice, or it may be boiled in milk or water, and be formed into a gruel, with the addition of a sufficient amount of Indian meal. It is nutrient and laxative.
BRAN (Furfures Tritici), in decoction or infusion, is sometimes employed as an emollient foot-bath; it is also taken internally as a demulcent in catarrhal affections. Its continued use causes a relaxed condition of the bowels. Bran poultices are sometimes used, warm, in abdominal inflammations, spasms, etc. Bread made from unsifted flour has been found beneficial in indigestion and constipation. The following forms a good bread for patients laboring under diabetes. Wash coarse wheat bran thoroughly with water on a sieve until the water passes through clear; dry this in an oven, grind it to a fine powder, and to 7 eggs, 1 pint of milk, ¼ pound of butter, and a little ginger, add enough of the bran flour to make a paste; divide into 7 equal parts, and bake in a quick oven, say from 20 to 25 minutes (P.).
Related Species.—Vicia Faba, Linné (Faba vulgaris, Moench), Horse bean, Windsor bean. The seeds of this plant furnish a flour known as FARINA FABAE. The seeds contain 2 parts of sugar, 2 parts of fat, 36 parts of starch, 9 parts of gummy matter, and 24 parts of legumin. The stalks and husks of this bean, when calcined and digested in white wine, are diuretic; the flowers, in aqueous infusion, are reputed efficient in gravel and gout; and the flour has long been a domestic remedy in Europe for diarrhoea.
Phaseolus vulgaris, Linné; Kidney bean; Common bean.—This bean furnishes a flour, FARINA PHASEOLI, whose composition does not vary greatly in proportions from that of the foregoing. The legumes are likewise diuretic, and, according to Soltsien (Archiv. der Pharm., 1884, p. 29), yield an alkaloid, phaseoline.
Lolium temulentum, Linné (Lolium arvense, Withering); Bearded darnel.—This plant is of interest chiefly from the fact that its fruit, or caryopsis, is frequently found with wheat or other grains, and is reputed to possess intoxicant and poisonous qualities. Though common in the grain fields of Europe and western Asia, it is not plentiful in this country, where it has been introduced by sowing grain containing its seed. The fruit is about ¼ inch long, oblong-ovoid, usually covered with the palae, smooth, with a convex outer and furrowed inner surface, and of a light-brown color. Internally, the seed is whitish, farinaceous, and has a starchy, bitter taste, but no odor. Several attempts have been made to isolate the toxic principle. The ordinary grain constituents are found in the fruit, a large portion of which (30 to 50 per cent) consists of circular, non-striated starch cells, about ⅓ the size of those of wheat. The toxic principles of the plant, according to Ludwig and Stahl (1864), are an amorphous, bitter, acrid, yellowish glucosid, dissolving in water, ether, and alcohol, and a fixed oil of an acrid character. Others believed the poisonous body to be an acid substance, while still others have ascribed its action to an oily, non-saponifiable body. Loliin, an acrid, dirty-white amorphous body, was isolated by Bley, in 1838. P. Antze (Amer. Jour. Pharm., 1891, p. 568) found what be supposed were two alkaloidal bodies, loliine (volatile) and temulentine, which were shown by Hoffmeister (1892) to be respectively impure ammonia and a mixture containing some of the narcotic principle discovered by him, to which be applied the name temuline. This is an amorphous alkaline body, probably at pyridine derivative, and soluble in water. An amorphous alkaloid and a nitrogenized acid were also detected by the same author. Temuline is poisonous (Amer. Jour. Pharm., 1892, p. 611). The symptoms produced by lolium are analogous to those of alcoholic intoxication. Horses, sheep, and dogs are poisoned by it, while cows and hogs remain unaffected, and ducks and quail fatten upon it. Headache, dizziness, disordered vision (sometimes yellow), tinnitus aurium, praecordial oppression and anxiety, lingual paresis, vomiting, diarrhoea, increased renal action, muscular tremors, cold perspiration, and deep narcosis, sometimes proving fatal, are the effects upon man. Lolium has been applied as a poultice to arrest pains of a neuralgic and rheumatic character, and in pleurisy. Liquors were once adulterated with darnel, and some even suspect its use at the present day, to add to the intoxicating qualities of some beverages.
PHALARIS, Canary seed.—The fruit of Phalaris canariensis, Linné, of the Mediterranean basin. It is much used as a food for birds, and, mixed with wheat or rye, has been ground into flour for the use of man. Poultices are also made of it. The fruit is small (⅙ inch) flattened, elliptic or ovate, covered by a shining yellow-gray paleae. The kernel is brownish externally, white internally, inodorous, and feebly bitter. The fruit (Fructus canariensis, or Semen canariensis) is composed mainly of starch.