How to make sausages
Practical Action
bacterial contamination that would reduce the shelf life of the sausages and/or cause a safety
hazard. The high risk of food poisoning from fresh sausagemeat is reflected in the legislation
in many countries, which may specify maximum levels of food poisoning bacteria, and may
also specify the hygiene and sanitation procedures that must be used when preparing
sausages. The ratio of lean meat to fat has an important influence on the quality of the
product, particularly in controlling shrinkage during cooking. Formulations that have higher
proportions of lean to fat show less shrinkage than formulae with more fat. A highly acceptable
pork sausage can be produced using a formulation that contains 35% fat. The addition of a
small amount of water or milk (3-5%) facilitates stuffing sausagemeat into casings. In many
countries, the legislation may also set out specific compositional and labelling requirements,
such as minimum meat content for sausages; added water over certain limits; or added
ingredients of different animal species that must be declared on the product label.
A meat grinder (Figure 1) forces meat under pressure
through a cylinder with sharp-edged ribs and then
through a series of holes in a perforated plate. As the
compressed meat exits through the plate, a revolving
four-bladed knife cuts it. The meat should be thoroughly
trimmed of fat and connective tissue, sprinkled with the
seasoning mixture and then ground twice: once through a
coarse plate (8-12 mm holes) followed by mixing in any
binder and a second grinding through a finer plate of 2-4
mm diameter holes.
Manual or motorised meat grinders are used for most
types of sausages, but processors who wish to make
emulsion-type sausages or those who can afford higher
levels of investment use bowl choppers (Figure 1).
These machines have a slowly rotating horizontal bowl
that moves the ingredients beneath a set of high-speed
rotating blades. Coarsely chopped meat and the other
ingredients pass several times beneath the blades until
it is chopped and blended to the required extent.
Figure 1: Meat grinder. Photo:
W. Weschenfelder and Sons,
www.weschenfelder.co.uk
Figure 2: Bowl chopper. Photo: Courtesy of
Union Food Machinery Ltd. www.ufm-
ltd.co.uk.
Emulsion-type sausages (e.g. ‘hot dogs’ or
frankfurters) are meat emulsions in which
tiny fat globules are dispersed in water that
contains a complex mixture of meat proteins
and gelatine. The structure of the emulsion
is set when the sausages are cooked, to
produce the characteristic texture of the
product. Factors that affect the stability of
the meat emulsion, and hence the texture of
sausages, include the type and quality of the
meat, which affect the water-holding
capacity and fat-holding capacity of the
meat proteins; the proportions of meat and
iced water to fat; and the time, temperature
and speed of homogenisation of ingredients
in the bowl chopper. Sausage texture is also
affected by the use of polyphosphates to
bind water into the sausage structure, but
these are not routinely used in small-scale
production.
After grinding, the sausagemeat is stuffed into casings that have been soaked in clean water or
dilute brine. A meat temperature of 2 - 4°C and good fluid properties of the sausagemeat are
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