Amygdala Dulcis. U. S., Br. Sweet Almond. Amygd. Dulc.
Preparations: Oleum Amygdalae Expressum
"The ripe seeds of Prunus Amygdalus dulcis De Candolle (Fam. Rosaceae). Preserve Sweet Almond in tightly-closed containers, adding a few drops of chloroform or carbon tetrachloride from time to time to prevent attack by insects." U. S. "Sweet Almond is the ripe seed of Prunus Amygdalus, Stokes, var. dulcis, Baill. Known in commerce as the Jordan almond." Br.
Semen Amygdali Dulce; Amandes douces, Fr. Cod.; Amygdalae Dulces, P. G; Süsse Mandeln, G; Mandorle doici, It.; Almendra dulce, Sp.
We are supplied with sweet almonds chiefly from Spain, Italy, France, and Southern California. They are separated into the soft-shelled and hard-shelled, the former of which come from Marseilles and Bordeaux, the latter from Malaga. From the latter port they are sometimes brought to us without the shell. In British commerce, the two chief varieties are the Jordan and Valencia almonds, the former imported from Malaga, the latter from Valencia. The former are longer, narrower, more pointed, and more highly esteemed than the latter.
Properties.—The shape and appearance of almonds are too well known to require description. Each kernel consists of two white cotyledons, enclosed in a thin, yellowish-brown, bitter skin, which is easily separable after immersion in boiling water. Deprived of this covering, they are called blanched almonds. On exposure to the air they are apt to become rancid; but, if thoroughly dried and kept in well-closed glass vessels, they may be preserved unaltered for many years.
Sweet almonds, when blanched, are without odor, and have a sweet, very pleasant taste, which has rendered them a favorite article of diet in all countries where they are readily attainable. They are, however, generally considered difficult of digestion. They are officially described as: "Ovate or oblong lanceolate, 17 to 25 mm. in length, 10 to 13 mm. in breadth and 4 to 7 mm. in thickness; seed-coat light brown with numerous parallel veins, thin and easily removed on soaking the seed in water; embryo straight, white, and with two plano-convex cotyledons; taste bland, sweet. Triturate Sweet Almond with water; a milk-white emulsion is produced which is not acid to litmus, and has no odor of benzaldehyde or hydrocyanic acid (bitter almond). The powder is creamy-white, exhibiting numerous very small oil globules, 0.001 mm. or less in diameter, and larger oil globules and crystalloids, the latter sometimes with adhering globoids; fragments of parenchyma of endosperm, containing oil-globules and aleurone grains; also occasional fragments of seed-coat with characteristic, more or less scattered, large, elliptical, thin-walled, strongly lignified epidermal cells and narrow, closely spiral tracheae. Starch grains are absent. Sweet Almond yields not more than 4 per cent. of ash." U. S. "About two and a half centimetres or somewhat more in length, nearly oblong in outline, more or less compressed, pointed at one extremity and rounded at the other. Testa cinnamon-brown, thin and scaly. Seed exalbuminous, containing two large planoconvex oily cotyledons. Taste bland; when triturated with water forms a white emulsion with no marked odor." Br. Shelled almonds are sometimes substituted by the kernels of the peach, plum and apricot. The stone cells in the epidermal layer of the almond are much larger than in the kernels of the substitutes. For microscopic distinctions see Winton and Moeller, "The Microscopy of Vegetable Foods." Almond cake a by-product in the manufacture of almond oil is largely used in the preparation of a class of detergent powders known as "almond meal." It is also used as a diabetic food and sometimes as an adulterant of ground spices and powdered drugs. By the analysis of Boullay, it appears that almonds contain 54 parts of fixed oil, 24 of protein, 6 of uncrystallizable sugar, 3 of gum, 9 of fibrous matter, 3.5 of water, and 0.5 of acetic acid, comprising loss. The protein is somewhat peculiar, consisting of amandin and emulsin, the latter being an enzyme. It may be obtained separate by treating the emulsion of almonds with ether, allowing the mixture, after frequent agitation, to stand until a clear fluid separates at the bottom of the vessel, drawing this off by a siphon, adding alcohol to it so as to precipitate the emulsin, then washing the precipitate with fresh alcohol, and drying it under the receiver of an air pump. In this state it is a white powder, inodorous and tasteless, soluble in water, and insoluble in ether and alcohol. Its solution has an acid reaction, and, if heated to 100° C. (212° F.), becomes opaque and milky, and gradually deposits a snow-white precipitate, amounting to about 10 per cent. of the protein employed. The distinguishing characteristic of the emulsin is that of producing certain changes noticed previously in amygdalin, which property it loses when its solution is boiled, although not by exposure in the solid state to a heat of 100° C. (212° F.). It consists of nitrogen, carbon, hydrogen, and oxygen, with a minute proportion of sulphur, and is probably identical with the synaptase of Robiquet. L. Portes has reported asparagin in sweet almonds. (N. R., January, 1877.) The fixed oil is described under the head of Oleum Amygdalae Expressum, to which the reader is referred. Sweet almonds, when rubbed with water, form a milky emulsion, free from the odor of hydrocyanic acid, the insoluble matters being suspended by the agency of the albuminous, mucilaginous, and saccharine principles.
Uses.—Sweet almonds have no other influence on the system than that of a nutrient and demulcent. The emulsion formed by triturating them with water is| a pleasant vehicle. From their nutritive properties, and the absence of starch in their composition, they are much used in the diet of diabetics, as originally recommended by Pavy. (Guy's Hosp. Rep., 1862, p. 213.) Almond meal or almond press cake is used for cosmetic purposes as an addition to the bath or to the water used in washing the face and hands. Much of the so-called almond meal used for this purpose is factitious or adulterated.