It consists of tying the casing of the sausage with a string, intertwining it with precise movements, to give it the correct portioning and shape and promote its maturation.
The binding must be accurate; it cannot be too tight, because it would cause the casing to break, nor too loose, because it would favor the formation of air inside it which would compromise the maturation.
There are many types of binding depending on the sausage, from the simplest ones such as the sausage which requires two knots at the head and tail of each of them, to more complex processes such as the coppa whose binding is both longitudinal and perpendicular and gives shape to numerous wedges to the mixture.