Handbook of Meat Processing

469

Chapter 27

Detection of Chemical Hazards

Milagro Reig and Fidel Toldr á

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 ’ 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