Coconut Oil or Butter.
—This is a very abundant natural fat and is obtained from the kernel of the coconut, especially the two species Cocos nucifera L. and Cocos butyracea L. At ordinary temperature coconut oil is of the consistency of fat. Its taste is pleasant, and it possesses an odor which is not disagreeable or undesirable. It differs from cacao butter in the ease with which it becomes rancid, at which time it takes on a very disagreeable flavor and taste. The coconut oil of commerce is distinguished by different names, according to the country in which it is made.
Cochin oil is a variety which is regarded as of the finest quality, being almost colorless, and is prepared in Malabar.
Ceylon oil is another very important variety made in the neighborhood of and imported from Ceylon. It is regarded as of somewhat inferior variety to Cochin oil, due probably to less care taken in the cultivation of the plant and the preparation of the oil.
Another variety of coconut oil is known as copra oil. The term “copra” is applied to the sun-dried or kiln-dried kernel of the coconut. In this dried state the fruit can be shipped in bulk and large quantities of it can be sent to Europe or other countries, where the oil is either obtained by extraction or by compression in a hydraulic press. This is regarded as of the least desirable quality.
Coconut oil resembles palm-nut oil in its chemical composition, with the exception of the relative proportion of palmitic acid. The specific gravity of coconut oil or fat at 40 degrees C. is about .912 and reduced to 15 degrees C. about .925. Coconut oil absorbs very little iodin, which is one of its principal characteristic chemical properties. The quantity of iodin absorbed may be taken as about eight percent of the weight of the oil. Coconut oil is one of the vegetable fats which resembles butter to some extent in the high content of volatile acid which it contains. If, under given conditions, butter may be regarded as having a volatile acid number of 27, coconut oil will have upon the same scale a volatile acid number of about 7, whereas ordinary vegetable oils and fats will have less than 0.5 on a similar scale. Coconut oil may be regarded as the one edible oil which approximates in constitution ordinary butter. Coconut oil has been used very extensively as an adulterant for oleomargarine, since by reason of its high volatile acid it brings that substance much nearer to the composition of butter or indicates a larger percentage of butter therein than is actually present. While it is used extensively as human food its principal value is for soap making. It appears as an edible fat under various names, such as “vegetable butter,” “lactine,” “nucoline,” “palmin,” etc. Coconut oil is also very extensively used in the manufacture of candies and confections.
Adulterations.
—Coconut oil is rarely adulterated. About the only adulteration of any consequence is that of the admixture with palm-kernel oil, which has properties very much like that of coconut oil. These two oils are ordinarily about the same price and therefore there is no inducement to practice adulteration.
Palm Oil or Fat.
—This oil is obtained from the fleshy part of the fruit of the palm tree Elæis Guineensis Jacq. and Elæis melanococca Gaertn. Extensive groves of these trees are found in Africa and also in the Philippines. In Africa they grow particularly upon the western coast. There is a large number of varieties of palm trees that afford this fat, but the two mentioned are the principal ones. This fat becomes solid at about the temperature of the body. It has a somewhat higher melting point than butter, which becomes liquid at a temperature of from 34 to 36 degrees C. When once solid the fat may be heated to 41 or 42 degrees before it again becomes liquid. Palm oil has rather a pleasant taste and is regarded as an edible fat of high quality, and is largely used as such by Europeans and in Africa and other countries where the fat is produced. The fat also has a very pleasant odor which is said to resemble somewhat that of violets. This pleasant odor is quite persistent and remains even in the fatty acids after they have been converted into soap. Palm oil is manufactured in the crudest possible way by the natives, and immense quantities are lost for this reason. By reason of this crude method, which leaves the oil in contact with the putrescible matter, palm oil often comes into the market in a rancid state or at least with a high content of free fatty acid. Appreciable quantities of water are also found in the crude article.