Fatliquoring is the simple process of using natural oil in water emulsions to carry lubricants into the skin fiber. Fatliquors penetrate quickly leaving a uniform layer of oil on the fibers deep inside the skin. Eggs, brains and spinal fluid contain natural emulsifying agents and oils. They are sometimes used alone, but often with extra oils added. The concept of fat liquoring is simple and easy to understand. Making egg yolk fat liquor is pretty much the same as making mayonnaise which is essentially oil emulsified with egg yolk.