Palm oil is extensively used in the manufacture of soap and also of candles. Mixed with cottonseed oil and mineral oil it is widely utilized in the tin-plate industry for coating iron. It has long been employed as a lubricant, particularly for railway-car axles. It is also used to give colour to butter-substitutes. Palm oils that are low in fatty acids are called "soft oils"; those con taining a high percentage of fatty acids are known as "hard oils." In tropical West Africa, especially in the Gold Coast, a specially prepared palm oil, called chop oil, is a staple article of food, being used in the same manner as olive oil, soy bean oil and butter are in temperate regions.
Palm-kernel oil or palm-nut oil, is extracted from the kernels of the crushed nuts either by pressure or with solvents, the yield ranging from 45% to 50%. It is a yellowish fatty oil more closely resembling coconut oil than palm oil. When fresh, palm-kernel oil is free from fatty acid, but, upon exposure to the air, quickly becomes rancid. Its principal constituents are triolein 15% to 25%; triglycerides of stearic, palmitic and myristic acids about 33%; and triglycerides of lauric, capric, caprylic and caproic acids '45% to 55%. The specific gravity of palm-kernel oil is 0.952; its
melting point varies f:om 78.6° F to 86° F; its saponification number is 247.6, and its iodine value is 13.4-13.6. It is extensively used in the manufacture of soaps, chocolate products, pharma ceutical preparations and perfumery.
Tropical West Africa is the main source of the world's supply of palm oil. Nigeria is the leading producer, exporting in 1926 113,267 tons, valued at £3,616,159. French Guinea and the Ivory Coast are the chief exporting dependencies of French West Africa. Ashanti, Gambia, the Gold Coast, Sierra Leone, the Cameroons, Dahomey, Togo and Liberia are also exporters of palm oil.
While palm oil is prepared directly from the fruit pulp in the regions where the oil palm grows, the hard-shelled nuts are largely exported in bulk and the extraction of oil from their kernels is made elsewhere. In 1926 the exports of palm kernels from Ni geria amounted to 249,100 tons, valued at £4,440,452. In 1927 the exports of palm kernels from the Ivory Coast were valued at 32,260,165 fr. and those from French Guinea at 26,424,468 fr. The total oil-equivalent of the products of the oil palm in all countries in 1926 was estimated at about 400,000 tons. (See OILS,