Thermal Food Processing

Thermal Processing of Meat Products 189
to be achieved in each of the product categories, based on quantitative risk assessments,
with a degree-of-safety margin built into these standards.
Performance standards prescribe the objectives or levels of performance (such
as pathogen reduction or standards for raw product) the establishments must
achieve. 27 This allows the processors to develop and implement processing procedures
customized to the nature and volume of production. Furthermore, the
processors can still follow the previous requirements that are being disseminated
as safe harbors.
The scientific validity of the performance standards has been questioned, and
recent deliberations and publication of a report by the National Academy of
Sciences 71 declared that the performance standards must be linked to a public
health goal and must incorporate a measure of effectiveness in meeting the public
health goal. The National Academy of Sciences defined performance standard as
“the degree to which a step or combinations of steps in the production, processing,
distribution and/or preparation of a food must operate to achieve the required
level of control over a hazard.”
Although these performance standards are prescribed within each country
depending on the prevalence and severity of food-borne illness, global trade
requires that science-based, verifiable standards be applied. The International
Commission for Microbiological Specification of Foods (ICMSF) developed the
concept of a food safety objective (FSO), on the lines of quality objectives in
quality assurance and quality management standards. 72 FSOs are the maximum
frequency or concentration of microorganisms or toxins of a microbiological
hazard in a food at the time of consumption that provides the appropriate level
of protection. FSOs are expressions of concentration of microorganisms or toxins
at the moment of consumption, while the performance criteria or standards are
concentrations at earlier stages of the food chain. 73
Control measures should be applied during food production to achieve the
defined FSO, and the outcomes of these measures are defined as performance
criteria or standards (USDA-FSIS). The FSOs are often stated as public health
goals, and to achieve this, performance standards or criteria should be established
with consideration to the initial levels of the hazard and changes (either increase
or reduction) occurring during production, processing, storage, preparation, and
use of the product. The performance criterion should be less than or at least equal
to the FSO and can be expressed as
H o − R + I ≥ FSO (6.3)
where FSO is the food safety objective, H o is the initial level of the hazard, R is
the cumulative reduction of the hazard, and I is the cumulative increase of the
hazard during processing, storage, and distribution of the product. These parameters
are expressed as log 10 units.
Examples of performance standards and criteria for lethality are shown in
Table 6.10 for meat and poultry products in the U.S. In most cases, Salmonella
spp. have been used as the pathogen of choice, with the intent that reductions in