Tallow is a rendered form of beef or mutton fat, processed from suet. It is solid at room temperature. Unlike suet, tallow can be stored for extended periods without the need for refrigeration to prevent decomposition, provided it is kept in an airtight container to prevent oxidation.
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.
Production of biodiesel 
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.
Niche uses 
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, shaving soaps from The Enchanted Bath, and soaps from Turkey and Italy.
Tallow also has a use in printmaking where it is combined with bitumen and applied to metal print plates to provide a resist to acid etching.
Historic applications 
Biblical mention 
In the third book of Moses (Lev. 3,14-17) the Israelites are forbidden to eat tallow. Instead they shall bring it as a burnt offering.
Tallow once was widely used to make moulded 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, moulded tallow candles, the "tallow dip"—a strip of burning cloth in a saucer of tallow grease—was an accessible substitute.
Early in the development of steam-driven piston engines, the hot vapors and liquids washed away most lubricants very quickly. It was soon found that tallow was quite resistant to this washing. Tallow and compounds including tallow were widely used to lubricate locomotive and steamship engines at least until the 1950s. (During WWII, the vast fleets of steam-powered ships exhausted the supply, leading to the large-scale planting of rapeseed because rapeseed oil also resisted the washing effect.) Tallow is still used in the steel rolling industry to provide the required lubrication as the sheet steel is compressed through the steel rollers. There is a trend toward replacing tallow-based lubrication with synthetic oils in rolling applications for surface cleanliness reasons.
The use of tallow or lard to lubricate rifles was the spark that started the Indian Mutiny of 1857. To load the new Pattern 1853 Enfield Rifle, the sepoys had to bite the cartridge open. It was believed that the paper cartridges that were standard issue with the rifle were greased with lard (pork fat), which was regarded as unclean by Muslims, or tallow (cow fat), which is incompatible with Hindu dietary laws. Tallow, along with beeswax, was also used in the lubricant for American Civil War ammunition used in the Springfield rifled musket.
|Nutritional value per 100 g (3.5 oz)|
|Energy||3,774 kJ (902 kcal)|
|- saturated||50 g|
|- monounsaturated||42 g|
|- polyunsaturated||4 g|
|Fat percentage can vary.
Percentages are relative to
US recommendations for adults.
Source: USDA Nutrient Database
The composition of the fatty acids is typically as follows:
- Saturated fatty acids:
- Monounsaturated fatty acids:
- Polyunsaturated fatty acids:
- Alfred Thomas (2002). "Fats and Fatty Oils". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a10_173.
- Thamsiriroj (2011). "The impact of the life cycle analysis methodology on whether biodiesel produced from residues can meet the EU sustainability criteria for biofuel facilities constructed after 2017", Renewable Energy, 36, 50-63.
- Schlosser, Eric (2001). Fast Food Nation: The Dark Side of All-American Meal. Houghton Mifflin. ISBN 0-395-97789-4
- "McDonald's Settles Beef Over Fries". CBS News. June 5, 2002. Retrieved 29 September 2011.
- "McDonald's USA Ingredients Listing for Popular Menu Items". Retrieved 29 September 2011.
- Hey Flux
- Cold rolling mill lubricant - US Patent 4891161
- Motavalli, Jim (5 February 2009). "Oil Goes ‘Green,' With the Help of Some Cows". The New York Times.
- National Research Council, 1976, Fat Content and Composition of Animal Products, Printing and Publishing Office, National Academy of Science, Washington, D.C., ISBN 0-309-02440-4; p. 203, online edition