OLEUM AMYGDALAE, B.P.
Related entries: Bitter almond, Sweet almond
Almond oil (Oleum Amygdalae Expressum, U.S.P.; Expressed Oil of Almond) is extracted by pressure from bitter or sweet almonds, in which it exists to the extent of about 40 per cent. It occurs as a clear, pale yellow, almost odourless, oily liquid, and has a bland, nutty taste. Specific gravity, 0.915 to 0.920 (0.910 to 0.915 at 25°). It should remain clear at a temperature of -10°, and should not congeal until it has been cooled to nearly -20° (absence of olive oil and lard oil). If 10 mils of the oil be mixed with 15 mils of a 15 per cent. solution of sodium hydroxide and 10 mils of alcohol, the mixture allowed to stand at a temperature of 35° to 40°, with occasional agitation, until clear, and then diluted with 100 mils of water, the clear solution thus obtained will, upon the subsequent addition of excess of hydrochloric acid, set free a layer of oleic acid, which, when separated, washed with warm water, and clarified by heating on a water-bath, will remain liquid if cooled to 15°. The fatty acid should also, on being mixed with an equal volume of alcohol (95 per cent.), yield a clear solution at 15°, and not deposit any fatty acids, nor become turbid on the further addition of one volume of alcohol (distinction from olive, arachis, cotton seed, sesame, and other fixed oils). The saponification value is from 188 to 200, and the iodine value from 95 to 100. Apricot kernel oil has a higher iodine value than almond oil, and is often substituted for it, or used to adulterate it.
Slightly soluble in alcohol, in ether (1 in 2.25), in chloroform or benzene in all proportions.
Constituents.—Almond oil consists chiefly of olein, with a small proportion of the glyceride of linolic acid, and other glycerides; it contains no stearin.
Action and Uses.—The oil is nutritive, demulcent, and laxative. It may be administered in the form of an emulsion. It is applied externally as an emollient for chapped hands and slight excoriations. It becomes rancid less readily than olive oil, and forms a whiter ointment with white wax and spermaceti; it is therefore preferred in the preparation of cold creams and similar toilet articles. It is the basis of many brilliantines and is added to lotions for the hair. Mixed with an equal quantity of lime water, one-eighth of its bulk of glycerin, and a suitable perfume, it forms "Glycerin and Lime Cream," a popular application for the hair. As a mild laxative dose for children, 4 mils (1 fluid drachm) of the oil maybe given. Sterilised almond oil is prepared by heating it for half an hour at 120° to 140° in small flasks or bottles, the necks of which are tightly plugged with cotton wool.
Dose.—4 to 16 mils (1 to 4 fluid drachms).
- Ceratum Galeni, B.P.C.—GALEN'S CERATE. Syn.—Unguentum Refrigerans; Cold Cream; Parogen Cold Cream.
- Almond oil, 50; white beeswax, 12.5; soft paraffin, white, 12.5; borax, 1; oil of rose, 0.1; rose water (undiluted), 25. Especially suitable for toilet use. If a similar preparation be required as a basis for medicaments the borax should be omitted, or preference should be given to the modification of Unguentum Aquae Rosae.
- Emulsio Olei Amygdalae, B.P.C.—EMULSION OF ALMOND OIL. 1 in 8.
- Used as a simple cough mixture. Dose.—8 to 30 mils (2 to 8 fluid drachms).
- Lotio Crinalis, B.P.C.—HAIR LOTION.
- Almond oil, 12.5; strong solution of ammonia, 12.5; oil of rosemary, 0.52; alcohol, 50; honey water to 100.
Sir Charles Locock's hair lotion or wash is prepared by mixing 120 grains of expressed oil of nutmeg or mace, 4 fluid ounces of spirit of rosemary, and 1 fluid ounce of olive oil, 2 fluid drachms of solution of ammonia, and 10 fluid ounces of rose water.
Synonym.—Oleum Amygdalae Essentiale.
Oil of bitter almond is obtained by distilling the moistened, bitter almond cake from which the fixed oil has been extracted by pressure. A similar oil, found in commerce, is obtained from the seeds of the apricot (Prunus Armeniaca, Linn.., which are imported in large quantities from Syria and California. When treated in the same way as bitter almonds, apricot kernels and peach kernels yield about 35 per cent. of fixed oil (Oleum Persicae), and about 0.6 to 1.0 per cent. of essential oil. The oil does not pre-exist in the almond cake, but is formed by the interaction of two constituents, amygdalin and emulsin, the products of the reaction being benzaldehyde, hydrocyanic acid, and dextrose. Hydrocyanic acid may be present in the natural oil to the extent of 4 or 5 per cent. When used in medicine it should contain not less than 2 per cent. and not more than 4 per cent. of hydrocyanic acid. Oleum Amygdalae Amarae, U.S.P., contains from 2 to 4 per cent. of hydrocyanic acid, and not less than 85 per cent. of benzaldehyde. For flavouring purposes the oil deprived of hydrocyanic acid (Oleum Amygdalae Essentiale sine Acido Prussico) should be used. To remove the hydrocyanic acid, the distilled oil is shaken with milk of lime and ferrous sulphate, whereby hydrocyanic acid is precipitated as calcium ferrocyanide; the unchanged benzaldehyde is then rectified by means of steam. In this way all traces of hydrocyanic acid are removed, and the oil may safely be used for any purpose. Another method of rectification is to shake the oil with a strong solution of sodium acid sulphite, which forms with the benzaldehyde a crystalline compound, from which the pure oil may be obtained by distilling with sodium carbonate. Oil of bitter almond occurs as a colourless liquid, having a characteristic odour; it is optically inactive. Specific gravity, 1.045 to 1.060 (1.040 to 1.055 at 25°). Boiling-point, 179°. On exposure to the air it is oxidised, and gradually deposits benzoic acid as a solid crystalline mass. This change takes place more readily in the oil freed from hydrocyanic acid, which evidently acts as a preservative. The presence of chlorine indicates contamination with, or substitution by, synthetically prepared benzaldehyde, although the latter, free from chlorine, has recently been placed on the market, so that the absence of chlorides is not an infallible indication of its purity. The following test may be applied to show the absence of chlorides:—Filter paper, free from chlorides, is moistened and placed on the inside of a large beaker. A folded strip of filter paper, saturated with the oil, is placed in a porcelain dish standing in a larger one, ignited, and immediately covered with the prepared beaker, which should be sufficiently large to cover the dish. The products of combustion are absorbed by the moistened paper, from which they are washed with distilled water, filtered, and treated with silver nitrate solution. No precipitate or even turbidity should be produced. To detect added nitrobenzene, dissolve 1 mil of the sample in 12 mils of absolute alcohol, and add 0.75 gramme potassium hydroxide; boil the liquid until it is reduced to about 4 mils, and leave it to cool; if the sample be pure no crystals form, but a brown colour is slowly developed, and the residual liquid is entirely soluble in water. In presence of nitrobenzene brown crystals of azoxybenzene, C12H10N2O, are formed, which are insoluble in water, and may be collected, dried by pressure, and weighed.
Sparingly soluble in water; soluble in all proportions of alcohol, ether, fixed, or volatile oils. Nitric acid dissolves the oil at ordinary temperatures without generation of nitric oxide vapours.
Action and Uses.—Oil of bitter almond is employed as a flavouring agent for emulsions, and for use in domestic culinary operations. For the latter purpose the oil freed from hydrocyanic acid should be used.
Dose.—1 to 6 centimils (0.01 to 0.06 milliliters) (1 to 1 minim).
- Aqua Amygdalae Amarae, U.S.P. and B.P.C.—BITTER ALMOND WATER. 1 in 1000.
- Used as a flavouring agent. Dose.—2 to 8 mils (1/2 to 2 fluid drachms),
- Aqua Amygdali Amarae, P.I.—BITTER ALMOND WATER, P.I.
- Strength, 0.1 per cent.
- Essentia Amygdalae Composita, B.P.C.—COMPOUND ESSENCE OF ALMOND.
- Oil of bitter almond free from hydrocyanic acid, 0.52; tincture of vanilla, 40; tincture of benzoin, to 100. Used as a flavouring agent,
- Spiritus Amygdalae Amarae, C.F., and U.S.P.—SPIRIT OF BITTER ALMOND. Syn.—Essence of Bitter Almonds,
- Oil of bitter almond, 1; alcohol (95 per cent.), 80; distilled water, to 100. Used chiefly as a flavouring agent. Average dose.—5 decimils (0.5 milliliters) (8 minims).
- Syrupus Amygdalae, U.S.P.—SYRUP OF ALMOND.
- Spirit of bitter almond, 1; orange-flower water, 10; syrup, to 100. Average dose.—4 mils (1 fluid drachm).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.