TALLOW (M.E. talugh, talg, cf. Du. talk, L. Ger. talg ; the connexion with O.E. taelg, dye, or Goth, tulgus,

See also:

• FIRM

firm, is doubtful)  , the solid oil or fat of ruminant animals, but commercially obtained almost exclusively from oxen and sheep . The various methods by which tallow and other animal fats are separated and purified are dealt with in the article Oils . Ox tallow occurs at ordinary temperatures as a solid hard fat having a yellowish white colour . The fat is insoluble in cold alcohol, but it dissolves in boiling alcohol, in chloroform, ether and the essential oils . The hardness of tallow and its melting-point are to some extent affected by the food, age, state of health, &c., of the animal yielding it, the firmest ox tallow being obtained in certain provinces of Russia, where for a great part of the year the oxen are fed on hay . New tallow melts at from 42.5° to 43° C., old tallow at 43.5°, and the melted fat remains liquid till its temperature falls to 33° or 34° C . Tallow consists of a mixture of two-thirds of the solid fats palmitin and stearin, with one-third of the liquid fat olein . Mutton tallow differs in several respects from that obtained from oxen . It is whiter in colour and harder, and contains only about 30 per cent. of olein . Newly rendered it has little taste or smell, but on exposure it quickly becomes rancid . Sweet mutton tallow melts at 46° and solidifies at 36° C.; when old it does not melt under 49°, and becomes solid on reaching 44° or 45° C . It is sparingly soluble in cold ether and in boiling alcohol .