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318 Cha pte r T e n

Within a risk analysis, the CODEX Alimentarius Commission has
developed the concept of quantitative microbiological risk assess-
ment (MRA), which will complement other quantitative food safety
targets that are currently under development, such as FSOs and POs
(Hugas et al. 2007). MRA has been driven by the requirement for
science-based risk assessment, as well as sanitary and SPS agreements.
MRA facilitates safe international trade of food and food products
(van Schothorst 2002).

10.4.1 Stages in Risk Assessment
Risk assessment is a well-established method of characterizing the
impact of foodborne bacteria on the food chain and consists of four
main stages: hazard identification, exposure assessment, hazard char-
acterization (or dose-response assessment), and risk characterization
(Fig. 10. 3).
The first stage in the process is identifying hazards. This involves
identifying the hazard in question and necessitates the collation of all
relevant data pertaining to the hazard. This stage will usually high-
light factors that contribute to the survival, mode of transmission,
and growth of the foodborne pathogen. Hazard identification focuses
on what can go wrong and how it might happen.
During exposure assessment, the pathways by which the hazard
can reach a host are identified, and the effects of process stages and
possible critical control points are assessed. Exposure assessment
evaluates the likelihood of these hazards occurring and the resulting
implications. Thus, the ultimate goal of exposure assessment is to
evaluate the occurrence and levels of a hazard in a food at the time of
consumption (Voysey and Brown 2000).
An accurate exposure assessment means that we need accurate
information on the following: the presence of the pathogen in raw
ingredients and the effect of food processing, distribution, handling,

Hazard identification

Exposure assessment

Hazard characterization

Risk characterization

FIGURE 10.3 Stages of risk assessment.