In industry, tallow is not strictly defined as beef or mutton fat. In this context, tallow is animal fat that conforms to certain technical criteria, including its melting point. It is common for commercial tallow to contain fat derived from other animals, such as lard from pigs, or even from plant sources.
Tallow consists mainly of triglycerides (fat), whose major constituents are derived from stearic and oleic acids. Tallow is used mainly in producing soap and animal feed.Tallow can be used for the production of biodiesel in much the same way as oils from plants are currently used. Because tallow is derived from animal by-products which have little to no value it avoids some of the food vs. fuel debate.
A significant use of tallow is for the production of shortening. It is one of the main ingredients of Native American food called pemmican. Before switching to pure vegetable oil in 1990, the McDonald's corporation cooked its French fries in a mixture of 93% beef tallow and 7% cottonseed oil. Currently, McDonald's French fries and hash browns contain beef flavoring derived from hydrolyzed wheat and milk that is added during production.
Many items of traditional goods are produced from tallow, which was widely available domestically. Tallow can also be used as flux for soldering. It is also the primary ingredient in some leather conditioners. Tallow used to be used commonly in high-end shaving soaps, in particular those of elite British firms such as Geo. F Trumper, Truefitt & Hill, and Taylor of Old Bond Street. While these firms have reformulated to a vegetable base, tallow-based soaps still exist, including the soaps from American firms, Williams Mug Shaving Soap, Nod Hill Soap, and soaps from Turkey and Italy.
Tallow once was widely used to make molded candles before more convenient wax varieties became available—and for some time after, as they continued to be a cheaper alternative. For those too poor even to avail themselves of homemade, molded tallow candles, the "tallow dip"—a strip of burning cloth in a saucer of tallow grease—was an accessible substitute.
