Cocoanut oil is used extensively in toilet soap making, usually in connection with tallow. When used alone the soap made from this oil forms a lather, which comes up rapidly but which is fluffy and dries quickly. A pure tallow soap lathers very much slower but produces a more lasting lather. Thus the advantage of using cocoanut oil in soap is seen. It is further used in making a cocoanut oil soap by the cold process also for "fake" or filled soaps. The fatty acid content readily starts the saponification which takes place easily with a strong lye (25°-35° B.). Where large quantities of the oil are saponified care must be exercised as the soap formed suddenly rises or puffs up and may boil over. Cocoanut oil soap takes up large quantities of water, cases having been cited where a 500 per cent. yield has been obtained. This water of course dries out again upon exposure to the air. The soap is harsh to the skin, develops rancidity and darkens readily.
_Palm Kernel Oil_, which is obtained from the kernels of the palm tree of West Africa, is used in soap making to replace cocoanut oil where the lower price warrants its use. It resembles cocoanut oil in respect to saponification and in forming a very similar soap. Kernel oil is white in color, has a pleasant nutty odor when fresh, but rapidly develops free acid, which runs to a high percentage.
_Palm Oil_ is produced from the fruit of the several species of the palm tree on the western coast of Africa generally, but also in the Philippines. The fresh oil has a deep orange yellow tint not destroyed by saponification, a sweetish taste and an odor of orris root or violet which is also imparted to soap made from it. The methods by which the natives obtain the oil are crude and depend upon a fermentation, or putrefaction. Large quantities are said to be wasted because of this fact. The oil contains impurities in the form of fermentable fibre and albuminous matter, and consequently develops free fatty acid rapidly. Samples tested for free acid have been found to have hydrolized completely and one seldom obtains an oil with low acid content. Because of this high percentage of free fatty acid, the glycerine yield is small, though the neutral oil should produce approximately 12 per cent. glycerine. Some writers claim that glycerine exists in the free state in palm oil. The writer has washed large quantities of the oil and analyzed the wash water for glycerine. The results showed that the amount present did not merit its recovery. Most soap makers do not attempt to recover the glycerine from this oil, when used alone for soap manufacture.