36.1 Introduction
Cleaning can be defined as the removal of soil' from surfaces and is important in all working and living environments (Dillon and Griffith, 1999). Soil can be described asmatter out of place' and may be of an organic or inorganic nature,
with or without associated microorganisms. In general terms the word soil has
become synonymous with dirt and Fig. 36.1 indicates possible sources of
contamination for ready-to-eat foods.
Cleaning is important for many reasons, not least of which is human
acceptance. While some people are forced, usually through poverty, to live in
dirty conditions, some anthropologists believe we have natural tendencies to live
in a clean, orderly environment (Curtis, 2001) and there is evidence to suggest
consumers avoid unclean food environments (Food Standards Agency, 2004).
Clean surroundings are increasingly believed to be important in the prevention
of disease transmission, and a dirty environment in the home, hospitals, work-
place, etc., can aid the spread of pathogens. Recent experience with SARS and
Norovirus outbreaks has refocused attention on the role of the environment in
the spread of disease. For the food industry, the adequacy of cleaning may be
critical in preventing cross-contamination, especially for pathogens such as
Campylobacter(Redmondet al., 2004), in the preparation of ready-to-eat foods.
However, it is not just microbial pathogens or their toxins in food that can affect
consumers' health, but increasingly the presence of small traces of human food
allergens, as a result of cross-contamination, can be a cause for concern.
An additional problem for food processors is the presence of food spoilage
organisms, which can cause off-odours, flavours or deterioration in food texture,
36 Improvingsurfacesampling and detectionof contamination...
C. Griffith, University of Wales Institute Cardiff, UK