Sodium tallowate is made from sodium hydroxide (a.k.a., caustic soda, or, lye); steam; and, animal (often, cattle) fat (i.e., tallow). This process, called saponification, breaks down the triglyceride (fat); frees the glycerol within; and, results in a sodium salt, sodium tallowate. It is usually combined with sodium cocoate, the sodium salt of coconut oil. Together, they are—with sodium palmate—major constituents of bar soap.