Fats are practically unaffected in the mouth and the stomach, and are indeed somewhat of an incubus there, because they have a tendency to interfere at least with gastric digestion by diminishing the outflow of gastric juice. When they reach the small intestine, however, they meet their fate in lipase (the fat-splitting ferment of the pancreatic fluid), and become split up into fatty acids and glycerine, constituting a milk-like solution termed an emulsion.