Preparation: Oil of Caraway
"The dried fruit of Carum Carvi Linne (Fam. Umbelliferae). Without the presence or admixture of more than 3 per cent. of other fruits, seeds or foreign matter. Preserve Caraway in tightly-closed containers, adding a few drops of chloroform or carbon tetrachloride, from time to time, to prevent attack by insects." U. S. "Caraway Fruit is the dried ripe fruit of Carum Carvi, Linn." Br.
Carui Fructus. Br.; Caraway Fruit; Carvies, Cumin des Pres, Carvi,. Fr. Cod.; Fructus Carvi, P. G.; Gemeiner Kümmel, Kümmel, Garbe, G.
The caraway plant is biennial and umbelliferous, with a spindle-shaped, fleshy, whitish root, and an erect stem, about two feet in height, branching above, and furnished with doubly pinnate, deeply incised leaves, the segments of which are linear and pointed. The flowers are small and white, and in erect terminal umbels, with an involucre, consisting sometimes of three or four bracts, sometimes of one only, and are destitute of partial involucre.
It is a native of Europe, growing wild in meadows and pastures, and cultivated in many places. It has been introduced in many places in this country, especially in the North. The flowers appear in May and June, and the seeds, which are not perfected until the second year, ripen in August. The root, when improved by culture, resembles the parsnip, and is used as food in Northern Europe. The fruits are the part used in medicine. They are collected by cutting down the plant, and threshing it on a cloth. Our markets are supplied partly from Europe, partly from our own gardens. The American fruits are usually rather smaller than the German. Under the name of Ajowan, the fruits of the Carum Ajowan, Bentham & Hooker (Ammi copticum L.) are largely used in India. (See Ajowan, Part II.) They contain about 4 per cent. of a volatile oil, which has the odor of the oil of thyme, and contains thymol; it may be used as an aromatic carminative. (See B. M. J., June 6, 1885.)
Caraway is officially described as follows: "Mericarps usually separated, crescent-shaped, 3 to 7 mm. in length, 1.5 mm. in diameter; externally dark brown with 5 yellowish filiform ribs; in transverse section nearly equilaterally pentagonal, the commissural surface with two vittae, the dorsal surface with a vitta between each of the primary ribs; oily endosperm large, enclosing a small embryo; odor and taste agreeably aromatic. Under the microscope, transverse sections of Caraway show an epidermal layer of slightly tangentially elongated cells with thick outer walls; a layer of several rows of tangentially elongated parenchyma cells, frequently more or less collapsed; a single, large, elliptical, brown vitta or oil-tube between each of the ribs and surrounded by small epithelial or secretion cells; in each of the ribs a single fibro-vascular bundle surrounded by a layer of thick-walled sclerenchymatous fibers; inner epidermis of broadly elongated cells with very thin side walls, being very frequently broken and closely coherent with the more or less brownish collapsed cells of the seed-coat; commissural surface with 2 large vittae and at the middle portion 2 large transverse hollow spaces formed by the separation of the tissues of the seed-coat on one side and the pericarp on the other, otherwise, the cells resemble those on the dorsal surface; endosperm large, cells polygonal with thick walls and containing a fixed oil and aleurone grains, the latter not infrequently containing a small rosette aggregate or prism of calcium oxalate. The powder is yellowish-brown, mostly of irregular, angular fragments; cells of endosperm, with aleurone grains each usually containing a rosette aggregate of calcium oxalate about 0.001 mm. in diameter; fragments with light-yellow vittae, together with nearly iso-diametric or polygonal, yellowish-brown, inner epidermal cells of pericarp; fragments with trachea and sclerenchymatous fibers, the latter 0.01 mm. in width, slightly lignified and with numerous oblique pores. Caraway yields not more than 8 per cent. of ash." U. S.
"Mericarps usually separate; each from about four to six millimetres long and about one millimetre broad; brown with paler primary ridges; slightly curved, tapering towards each end, and glabrous. In transverse section, six vittae in each mericarp. Odor and taste aromatic. Ash not more than 9 per cent." Br.
They have an agreeable aromatic odor, and a sweetish, warm, spicy taste. These properties depend on an essential oil, which they afford largely by distillation. (See Oleum Carvi.) The residue is insipid. They yield their virtues readily to alcohol and more slowly to water.
"Drawn caraway seeds," a term applied to such as have been recovered from the still residue after obtaining the volatile oil, are used to adulterate caraway; the exhausted "seeds" are much darker in color than are the genuine and are less odorous. (P. J., 1896,150.) While this is the principal form of adulteration, they may contain large amounts of stems, gravel, sand, dust, weed seeds and other impurities.
Uses.—Caraway is a pleasant stomachic and carminative, occasionally used in flatulent colic, and as an adjuvant or corrective of other medicines. The dose in substance is from fifteen to thirty grains (1-2 Gm.). An infusion may be prepared by adding two drachms of the seeds to a pint of boiling water. The volatile oil, however, is most employed. (See Oleum Cari.) Three and a half ounces of the oil of caraway caused violent vomiting and abdominal pain, with loss of consciousness, ending, however, in recovery. The urine contained both acetone and albumin. (Cb. I. M., xxii, 1902.) In culinary operations the seeds are added to cakes, to which they communicate an agreeable flavor, while they stimulate the digestive organs.
Dose, fifteen to thirty grains (1-2 Gm.).
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.