Shirring of the casing – it is process of compression of the big piece of casing into the shirred briguette of the given size.

Actually gathering of a sleeve of sausage casing in folds and formation in a kind of briquette is made on the special equipment – shirred machines. They can have various constructions, but the main idea of the process remains the same: the casing for shirring is delivered in rolls, on the shirred machine it is taken up from the reel and filled with air. The casing inflated with air stretches on a pipe which has diameter that will get after the process shirred briquette. On shirring pipe the casing gathers in folds. After shirring of necessary length has been made, the casing is cut off and compressed. The most important thing in the process of casing`s shirring is coefficient of compression which is defined by the relation of length of not shirred casing to the length of shirred briquette. The modern equipment allows to reach coefficient of compression 1:100 and more.

In case when on shirred and compressed sleeve of casing is put on a grid for fixation of the form and density of the shirred briquette - then it is "soft" shirring.

For reception of the "rigid" form of shirring the surface of the casing is treated by special composition, then the casing sleeve is very densely compressed and dried up. After that the form of shirred briquette remains fixed, stable and doesn't need additional fixing by a grid.

All kinds of casings can be shirred, and some of them are delivered to the consumer only in shirred form. There are two types of them:

- type А – intended for using on automatic equipment for frankfurters and has closed end of the shirred stick;

- type P – intended for using on twist-injector with twisted device and for twisting by hands and has open end of the shirred stick;

Using of shirred casing in meat-processing industry has variety of essential advantages.

Considerable economy of time:

- Usage of the shirred casing allows to fill during one running cycle with forcemeat without a stop the big lengths of casing, and because of this can be reached  continuity and manufacturability of the filling process;

- shirring allows to avoid the process of unwinding of the casing from the sheave and putting on of casing  on the stuffing horn manually;

- shirring simplifies the process of soaking of the casing as allows to avoid additional operations, such as spilling inside the sleeve;

- Usage of the shirred casing as a whole reduces labor input of processes of preparation of the casing for using and formation of sausage sticks, raises labor productivity.

It is less probability of occurrence of infringements of integrity of the casing during its preparation for using:

- As shirring allows to avoid process of unwinding of the casing from the sheave and putting on of casing  on the stuffing horn manually, the risk to traumatize the casing decreases also;

- Soaking of the casing by water inside and outside is going in more evenly, than if the casing was soaked in the form of a sleeve with a spilling water from inside.

The casing expense decreases:

- The casing metric area in a briquette makes up 38, 5 meters;

- Manually such quantity of a casing to shirre on stuffing horn is impossible , and casing wastes during manual shirring will be more.

Usage of the shirred casing is the integral attribute of the modern meat-processing enterprise. Because of this leaders of meat-processing industry work exclusively with the shirred casings.