Wild growth unknown; prone to go wild. It is widely cultivated in states with a subtropical climate of both continents. It grows well in the tropics, but does not bear fruit.
Evergreen tree 3-7 m tall. Leaves 5-8 cm long, opposite, almost sessile, leathery, oblong or lanceolate, entire, silver-gray below from the abundance of hairs. The flowers are small, white, in 15-30-flowered racemes, sitting opposite in the axils of the leaves. The fruit is an oblong or spherical drupe up to 30 mm long with fleshy, oily flesh and a hard one-seeded stone. Depending on the variety, mature drupes can be black, reddish, purple or whitish.
Fatty oil is found both in the pulp (50-70%) and in the seeds (within 20%). It consists of almost pure triolein: iodine number 75-88.
From fresh olives, medical (Oleum Olivarum), food (Provencal and other varieties) and technical (“wooden”, etc.) olive oil are obtained. Medical oil is obtained by cold pressing; it is colorless. It is the best solvent for camphor injectables, sex hormone products and their synthetic counterparts, and some other medicinal products.
An analogue of olive oil is almond fatty oil (Oleum Amygdalarum), obtained from the seeds of Amygdalus communis L. (Rosaceae), which grows wild in Central Asia, Transcaucasia, Asia Minor and is widely cultivated in the subtropics of both continents.
The plant contains liquid fats (oils).
PLANTS CONTAINING FATS (FATTY OILS)
Fats consist almost entirely of triglycerides of high molecular weight fatty acids. They are accompanied by pigments, sterols, vitamins and some other fat-soluble substances.
The fatty acids that make up triglycerides can be saturated or unsaturated. Most often, triglycerides contain the fatty acids listed in the table.
Fats are not individual substances – they are mixtures of triglycerides. In the formation of fats, the law of maximum heterogeneity prevails – more than 1300 currently known fats are formed by “multi-acid” triglycerides, and fatty acids of different composition (for example, stearinodiolein, palmitinooleinolinolein, etc.). Fats, consisting of “one-acid” triglycerides, are relatively rare in nature (olive oil is triolein, castor oil is triricinolein).
The properties of fats are determined mainly by the composition of fatty acids and their quantitative ratio. Saturated fatty acids form triglycerides of a dense consistency (at traditional temperature), and the density increases with the increase in the number of carbon atoms in the acid (see table). Unsaturated fatty acids form liquid triglycerides.
Liquid fats (oils), spread with a thin layer, can remain liquid (non-drying fatty oils) or, oxidized, gradually turn into a resinous film (drying – a dense film and semi-drying – a soft film). Fatty oils dominated by oleic acid triglycerides are non-drying. The more linoleic and linolenic acids in oils, the more they are prone to drying out, as can be judged by the iodine number (the number of grams of iodine that can join 100 g of fat at the place of double bonds of unsaturated acids). Approximate limits of iodine numbers: non-drying 80-100, semi-drying 100-140, drying oils 140-200.
Most vegetable fatty oils are obtained by pressing or extracting raw materials with volatile solvents. Freshly obtained (“raw”) fats are purified (refined).