Dry-Cured Ham 353
Jim é nez - Colmenero et al. 2006 ) and the
crossbreed used (Armero et al. 2002 ). The
detection of any undesirable oxidation and/or
development of rancid off - fl avors is essential
at this stage. Easy controls for unsaturation
and freshness consist of the measurement of
the iodine index and the acid index, respec-
tively (Toldr á 2002 ).
In general, hams from heavy pigs give
better quality (reddish color, higher content
of intramuscular fat, better marbling, etc.)
than industrial - standard pigs, mainly due to
the age but also to the type of crossbreeding.
Main reasons for differences due to genetics
are related to chemical and biochemical char-
acteristics of respective muscles (i.e., differ-
ent enzyme profi le) (Toldr á et al. 1996 ).
Other Ingredients
Marine salt is the main ingredient for dry -
cured ham. Particular fl avors depend on the
salt ’ s mineral and trace element composition.
Salt mainly contributes to a reduction in
water activity, partial solubilization of myo-
fi brillar proteins, and typical salty taste
(Toldr á 2002 ).
Nitrate and nitrite are added to the curing
salt in order to achieve levels of 120 – 150 mg/
kg in the ham just at the beginning of the
process. Nitrite contributes to the preserva-
tion effect against pathogens, as well as to the
typical red color formation in ham by forming
nitrosomyoglobin, but it also contributes to
certain antioxidant activity (Pegg and Shahidi
2000 ).
Processing Stages
The processing of dry - cured hams appears
simple, but complex chemical and biochemi-
cal reactions take place inside hams. There is
a minimum length of time for the muscle
enzymes to develop the characteristic fl avor.
Main processing stages are the reception
of hams, salting, post - salting, ripening, and
drying, as shown in Figure 20.2.
sumed after cooking (pan frying, baking in
the oven, or roasting). Some of the most well
known are produced in Kentucky and
Virginia, but they are also produced in
Tennessee, North Carolina, Pennsylvania,
and Missouri (Stalder et al. 2007 ).
Hams in China
Ham production in other areas of the world
has also grown signifi cantly in recent years.
Good examples of typical hams produced
in China are the Yinghua hams, traditionally
produced in the Jinhua district, a moun-
tainous region in China with four distinct
seasons (Du and Ahn 2001 ; Zhou and Zhao
2007 ), Xuanwei hams, produced in the
Yunnan province in the southwest of China
where there are high altitudes (Yang et al.
2005 ), and Rugao hams in the Jiangsu
province.
Raw Materials
Raw Hams
It is important to discriminate DFD (dark,
fi rm, and dry) hams because their high pH
can prompt the development of undesirable
microorganisms. This type of ham may be
used for other types of products. On the other
hand, PSE (pale, soft, and exudative) hams
create some diffi culties to processors because
of an excessive rapid water loss due to their
lower water - binding capacity (Arnau et al.
1995 ) and an unpleasant salty taste due to an
excess of salt intake. This type of ham
requires a specifi c control during processing.
Frozen/thawed hams must be carefully con-
trolled when received at the factory and must
be thawed before processing. Selection of
hams by weight facilitates the control of time
during the salting stage, as will be described
later. The content and composition of fat is
important for correct fl avor development. Fat
composition in fatty acids depends on the
feed given to pigs (Toldr á et al. 1997b ;