Handbook of Meat Processing

302 Chapter 16

fat is very important for fl avor development,

while the composition in fatty acids mainly

depends on the feed given to pigs (Jim é nez -

Colmenero et al. 2006 ) and the crossbreed

used (Armero et al. 2002 ). Any undesirable

aroma or oxidative development (i.e., ran-

cidity) must be detected before processing.

Hams are usually boned before brine

injection.

The salt added in the brine may reach a

fi nal content of around 2% in the ham. Salt

contributes to a reduction in water activity,

partial solubilization of myofi brillar proteins,

and typical salty taste. Nitrite is also added

at levels of 120 – 150 mg/kg and contributes to

typical light pink color formation, antioxi-

dant activity, and preservation effect against

pathogens (Pegg and Shahidi 2000 ). In order

to avoid risks of nitrosamine formation, the

addition of ascorbates or erythorbates at

levels of 200 – 400 mg/kg is recommended.

Some sugar (dextrose) may be added for taste

purposes. Phosphates, at levels from 0.15%

to 0.3%, given as P 2 O 5 , may be allowed in

some countries, depending on the quality of

the product. Polyphosphates contribute to

improvements in ham ’ s water retention.

Poor - quality hams may also contain some

nonmeat ingredients like milk powder,

caseinate, soy proteins, potato fl our, or car-

rageenan, to act as thickeners and to improve

water retention.

Processing Technology

Cooked ham is also known as canned ham.

The scheme for the main processing stages is

shown in Figure 16.1. Main stages are the

reception of hams, the brine injection, tum-

bling and massaging, cooking, and cooling.

All these stages are described below.

Reception

Refrigerated hams or frozen/thawed hams are

received and controlled by weight. The pH is

measured in order to detect any PSE or DFD

water, although the fi nal quality mainly
depends on the raw material and the process-
ing conditions used.
Generally, modern tumbled hams are
manufactured by injecting the pork meat with
brine, after which the ham is tumbled and
then cooked. The Wiltshire method consists
of an old, traditional method of curing,
whereby the pork leg is immersed for several
days in brine, which yields a high - quality
product (Delahunty et al. 1997 ). In addition,
there is a method for producing sweet - cure
hams that have a low salt content and a
blander fl avor, where sugar is generally
added to the brine (Delahunty et al. 1997 ).
Many other cooked hams are manufac-
tured in, and receive the name of, the region
where they are produced. This is the case of
Italian prosciutto cotto or French hams
(Jambon de Bourgogne, Jambon de Reims,
etc.) (Frentz 1982 ).

Raw Materials

Refrigerated hams or frozen/thawed hams
must be carefully controlled when received
at the factory and before further processing.
These hams must be hygienically manipu-
lated and controlled in order to have a product
with a good shelf life. The water - holding
capacity of the hams used as raw material is
essential in order to minimize the cooking
losses. Water - holding capacity is linked to
the pH of the ham; pH values within the
range 5.8 to 6.2 may assure good water
retention. Incidence of PSE (pale, soft, exu-
dative) and DFD (dark, fi rm, dry) hams
must be registered. In the case of PSE hams,
they have a low pH value and a low water -
holding capacity that will give higher cooking
losses and drier hams. DFD hams may be
used; their high pH can facilitate water reten-
tion but makes them prone to microbial
growth. These hams are heat - treated, avoid-
ing risks for microbial growth, but they may
present some preservation problems com-
pared with normal hams (Toldr á 2006a ). The