Sensory Evaluation of Meat Products 459Samples of fat were analyzed for androste-
none and skatole and fat samples, then
grouped according to levels of androstenone
and skatole. In terms of androstenone, there
were low, medium, and high levels, with con-
centrations of androstenone of < 0.5 μ g g^ −^1 ,
0.5 to 0.99 μ g g^ −^1 , and 0.99 μ g g^ −^1 respec-
tively. For skatole, the defi nitions of low and
medium were < 0.8 μ g g^ −^1 and ≥ 0.08 μ g g^ −^1.
Assessors rated samples on a fi ve - point scale
where 1 was minimum and 5 was maximum
for each sensory attribute of boar odor and
boar fl avor. Samples were compared across
six combinations of androstenone and
skatole, using the convention of LL (i.e., low
androstenone and low skatole), LM, ML,
MM, HL, and HM. The analysis showed that
cooked pork boar odor and fl avor increased
signifi cantly in LM and MM groups when
compared to control castrate samples, while
in the dry cured ham only HM samples were
differentiated from the control group. A
further analysis compared cooked pork loin
and dry - cured ham from entires and castrates,
and as expected, boar odor and fl avor was
lower in castrates and higher in entires in
cooked pork. In the equivalent dry - cured
ham samples, boar odor was higher in entires
than in castrates. However, generally low
ratings were given for boar fl avor. Dry - cured
ham from castrated pigs had improved aroma
and taste. It was concluded that in cooked
pork loin, boar taint was much more intense
than in dry - cured ham from the same pigs.
Therefore, the process of curing (which in
this case used a curing solution of 98%
sodium chloride plus 2% potassium nitrate
and sodium nitrate in equal proportions, and
then dry salting with coarse sea salt) demon-
strated the changes in meat sensory charac-
teristics that occurred during processing.
Earlier reference was made to the work of
Nute (1987) in producing a sensory map of
ham products. A similar approach has been
adopted by Garc í a - Gonz á lez et al. (2008)
when assessing dry - cured ham, where the
emphasis is on the relationship between vola-taint, barnyard, smoky serum, and pungent
aromatics; increases in sour, salty tastes; and
an increase in astringency in the mouth. It
was postulated that the longer processing
time of 12 months would allow more time for
underlying biochemical changes to take place
that could produce increases in volatile fatty
acids.
Multivariate analysis (factor analysis) was
also used to investigate the development of
dry - cured fl avor. After 12 months, three main
factors were identifi ed, “ cured fl avor, ” “ off -
fl avor, ” and “ pork fl avor, ” whereas at 7
months, the dry - cured fl avor was not fully
developed. In this trial it was interesting to
note that “ boar taint ” increased over the dry -
curing time. Boar taint, which is used as a
general term, has at least two compounds
responsible, which differ in their origin.
Androstenone, a hormone - like compound, is
produced in the testes and then migrates to
the salivary glands in the pig. It is also a good
indicator of boar taint in back fat as a result
of the lipophilicity and hydrophobicity of
androstenones. Skatole, the other major con-
tributor to boar taint, is produced by the
breakdown of tryptophan in the hind gut of
the pig. The compound is both fat and water
soluble. An extensive study of how boar taint
is perceived by assessors is given by a series
of papers by Annor - Frempong et al. (1997a,
b, c, 1998) and Nute et al. (1988). Although
a full description of these works is outside
the scope of this present chapter, these papers
may be of interest to those working on boar
taint.
Work described by Banon et al. (2003)
investigated the differences in boar taint in
cooked pork loin and dry - cured ham from the
same pigs as assessed by a trained panel.
Meat in this study came from entire males
and castrates from two lines of pigs, Large
White x Hungarian Duroc females crossed
with Landrace x Danish Duroc males and
Landrace x Large White females crossed
with Large White males. All pigs were
slaughtered at around a liveweight of 105 kg.