469
Chapter 27
Detection of Chemical Hazards
Milagro Reig and Fidel Toldr รก
Introduction
The development of modern analytical tech-
nologies linked to epidemiologic studies and
investigations on the safety aspects of food
components has revealed in recent decades
that some toxic compounds may be present
or generated in certain types of meat and
processed meat. Three groups of compounds
have received great attention because they
are potential carcinogens, and, even when not
present in the raw meat, they can be gener-
ated during further processing or cooking.
These groups are nitrosamines, heterocyclic
amines, and polycyclic aromatic hydrocar-
bons. N - nitrosamines can be generated under
certain processing conditions when using
nitrite as a preservative. The polycyclic aro-
matic hydrocarbons (PAH), which are gener-
ated in certain smoking processes, can also
be produced when cooking at high tempera-
tures. This is also the case with the heterocy-
clic amines, which are generated when
cooking at high temperatures. In fact, diets
associated with meats cooked at high tem-
peratures may increase the risk of certain
types of cancer (Jakszyn et al. 2004 ). Other
compounds that can also exert adverse effects
on consumers โ health are the biogenic amines
that are generated by the microbial decarbox-
ylation of certain amino acids, which have
potential vasoactive or psychoactive toxico-
logical effects. Amines may also constitute a
source of secondary amines that can react
with nitrite and produce nitrosamines with
potential carcinogenic activity. Finally, other
toxic compounds may result from the oxida-
tion of lipids and proteins, as well as other
products that may be present in the raw
materials used for processing (veterinary
drug residues, environmental contaminants,
etc.). The main routes for the presence of
these compounds in meat are summarized in
Table 27.1.
Controls and effective corrective mea-
sures (i.e., control of raw materials, reduction
in the addition of nitrite, control of microbial
decarboxylase activity, etc.) can been taken
to minimize this problem in cooked, cured,
and dry - cured meat products. All these haz-
ardous compounds and the main analytical
techniques used for their control are briefl y
described in this chapter.
N - nitrosamines
Nitrosamines are N - nitroso compounds that
have received much attention in the last 50
years due to their recognition as potential
carcinogenic compounds. Nitrosamines are
formed in cured meats through the reaction
of nitrous acid in its dissociated form,
generated from nitrite, with secondary
amines. Some of the most important nitro-
samines detected in cured meats are N -
nitrosodimethylamine, N - nitrosopirrolidine,
N - nitrosopiperidine, N - nitrosodiethylamine,
N - nitrosodi - n - propylamine, N - nitrosomorp-
holine, and N - nitrosoethylmethylamine.
Some are carcinogenic in a wide range of
animal species. In addition, a large number
of nonvolatile nitroso compounds, higher in