2. In food engineering, ham sausage is a system called "emulsified meat". Its key is to break down fat into fine particles and distribute them evenly throughout the intestine. So it is almost impossible to distinguish the fat with the naked eye. Generally speaking, it is fat, more or less. In order to make these fats disperse evenly, it is necessary to extract protein from lean meat as an emulsifier to stabilize the "ground" fat particles. The extraction of protein is not an easy task. Usually lean meat is "beaten" into meat paste, and more protein can be extracted at high salt concentration.