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Chapter 6
However, a number of authors have described Salmonella biofilm
formation with a limited number of strains [67, 71], with a single serovar
[73, 98, 102, 106, 138, 147, 187-188, 190] or using a single biofilm
substrata [111-112, 159, 165, 191]. The work presented in this thesis
makes a useful contribution to the knowledge of Salmonella enterica
biofilm density on surfaces, as multiple strains within three serovars of
interest S. Agona, S. Typhimurium and S. Enteritidis, were compared.
6.1. Replicating food processing environments
There are inevitable difficulties in applying findings from research in
controlled laboratory conditions to food processing environments although
it is important that experimental design takes account of real world
environments, in so far as possible. For example, the use of multiple
surfaces may allow a more comprehensive understanding of biofilm
density on surfaces frequently associated with food processing
environments. The conditions used during biofilm studies such as the
reactor model chosen, temperature, nutrient flow and concentration can
influence the density of biofilm formed [32, 73, 102, 117, 188]. Therefore,
the biofilm density was assessed for 12 S. enterica strains using the CBR
and microtitre plate based models for 48 and 168 hours. The experiments
were also repeated to investigate the repeatability and accuracy of the
findings.
Previous research indicates that the properties of a Salmonella biofilm
formed under a specific set of conditions may be surface specific [71, 95,
102]. Therefore, a practical approach was undertaken in this work to use a
biofilm model that allowed inclusion of multiple surfaces commonly found
in food processing environments to be assessed simultaneously within one
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