Of the natural fats or glycerides contained in oils the most important in addition to palmitin are stearin and olein, and these it may be sufficient to regard as the principal fatty bodies concerned in soapmaking.
The neutral fats are composed of fatty acids and glycerin.
These discoveries of Geoffroy and Scheele formed the basis of Chevreul's researches by which he established the constitution of oils and the true nature of soap. In the article Oils it is pointed out that all fatty oils and fats are mixtures of glycerides, that is, of bodies related to the alcohol glycerin C 3H5(OH)3 i and some fatty acid such as palmitic acid (C 16 H 31 0 2)H.
Numerous varieties of soaps are made; the purposes to which they are applied are varied; the materials employed embrace a considerable range of oils, fats and other bodies; and the processes adopted undergo many modifications.
The most important of the animal fats are those of the ox and hog, and of the vegetable oils cotton-seed and coco-nut; it is also to be remembered that resin, although not a fat, is also important in soap-making.