How to make sausages
Practical Action
required for stuffing fresh sausages. Traditionally, sausage casings were made of cleaned pig
or sheep intestines, but they are now also made from collagen, cellulose, or other plastics.
Casings of different diameters include: wide (22 - 24 mm), medium (20 - 22 mm), narrow
medium (18 - 22 mm) and narrow (16 - 18 mm). Medium sized casings are preferred for pork
sausages, especially if they are formed into links, and narrow casings are more suitable for
beef sausages. Manual or motorised sausage stuffers (Fig. 3), have a cylinder that contains the
sausage meat and a moveable plunger that forces the meat through an outlet pipe (or ‘horn’)
into the sausage casing. The casings are filled to maximum capacity to prevent air becoming
trapped, which could discolour the sausages. Linking is carried out by twisting the stuffed
casing at regular intervals to give the length of sausage required by the local market. This
varies widely but short links of 5 - 7 cm or long links of 10 - 15 cm are common lengths.
Linking may be done by hand or using a linking attachment to the sausage stuffer.
a) b)
Figure 3: Sausage forming equipment, a) manual sausage stuffer (SAP at
http://sapbologna.it), b) Motorised sausage stuffer (REX-Technologie GmbH & Co. KG at
www.rex-technologie.com)
After stuffing and linking, fresh sausages should be chilled rapidly by hanging them in a
chiller and they should be kept at refrigeration temperatures of 0 - 4°C to give a storage life of
up to 6 days. Good circulation of air in a refrigerated storage room is necessary but if the air
circulation is too rapid it will cause excessive drying and shrinkage of the sausages. The
correct air humidity is 75 - 80% to prevent excessive loss of moisture and avoid mould growth.
Sausages should be kept at refrigeration temperature until they are cooked. This requires a
cold distribution chain from the processor to the retailer or food service outlet. In some
countries the measures to control the temperature during distribution and sales are controlled
by law. Because of the risk from food poisoning bacteria, fresh sausages should be heated
sufficiently to destroy any bacteria that are present at the centre of the product. The
temperature and time of heating should also be sufficient to produce the required changes to
the flavour and colour of the sausages.
Fermented sausages
Fermented sausages are produced using similar methods to fresh sausages but the ground
meat is fermented (or cured) either before or after stuffing. The stuffed sausages are then
smoked, dried or aged to make a product that can be consumed without further cooking.
Unlike fresh sausages, the long shelf life of fermented sausages is due to their low moisture
content (low water activity), acids produced during the fermentation, and smoke compounds if
the sausages are smoked. These preservation factors prevent the growth of pathogens and
spoilage micro-organisms and allow the sausages to be stored at room temperature and eaten
without cooking.
The ingredients used in fermented sausages include coarsely or finely chopped meats, fat,
lactic acid bacterial starter culture, spices, sugar, salt and curing salts (sodium or potassium
nitrite and/or nitrate). Meat used for fermented sausages should be carefully trimmed to
remove sinews and soft inter-muscular fat. Methods of grinding and chopping depend on
whether the sausage is intended for slicing or spreading: in general, finer grinding produces
improved spreading properties. Beef is normally chopped first and then the pork and other
ingredients are added. Salt and curing salts are added at the end of chopping. The sugar is
added to speed up the growth of lactic acid bacteria and curing salts are used to prevent the
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