Olive oil), the soft fats which may be fluid in their country of origin (e.g.
If care be exercised in the process of rendering animal oils and fats or expressing oils in the cold, the products are, as a rule, sufficiently pure to be delivered to the consumer, after a preliminary settling has allowed any mucilaginous matter, such as animal or vegetable fibres or other impurities, and also traces of moisture, to separate out.
In this field he contributed to our knowledge of the manufacture of iron and steel, sulphuric acid, glass and paper, and in particular worked at the saponification of fats with sulphuric acid and the utilization of palmitic acid for candle-making.
The waxes can be classified similarly to the oils and fats as follows: - The table enumerates the most important waxes: - Waxes There are only two liquid waxes known, sperm oil and arctic sperm oil (bottlenose-whale oil), formerly always classed together with the animal oils.
Even if a mixture of several oils and fats be present, the iodine value assists greatly in the identification of the components of the mixture, and furnishes the most important key for the attacking and resolving of this not very simple problem.
The specific gravities of oils and fats vary between the limits of o-910 and 0.975.
The true chemical constitution of oils and fats was first expounded by the classical researches of Chevreul, embodied in his work, Recherches sur les corps Bras d'origine animale (1823, reprinted 1889).
The number of chemicals which have been proposed from time to time for the purification of oils and fats is almost legion, and so long as the nature of oils and fats was little understood, a secret trade in oil-purifying chemicals flourished, With our present knowledge most of these chemicals may be removed into the limbo of useless things.
The normal alcohols containing r to 16 carbon atoms are liquids at the ordinary temperatures; the higher members are crystalline, odourless and tasteless solids, closely resembling the fats in appearance.
It is obtainable from most natural fatty bodies by the action of alkalis and similar reagents, whereby the fats are decomposed, water being taken up, and glycerin being formed together with the alkaline salt of some particular acid (varying with the nature of the fat).