Food Protection Trends - January/February 2022 - 46

In cases for which routine hygiene practices may be inadequate,
changes should be made that do not endanger human
health or compromise food quality. To identify new hygiene
strategies and address current problems, it is necessary to clarify
the biofilm formation characteristics of thermophiles with
laboratory-scale studies that mimic production environments
in the dairy industry.
Under high shear stress, bacteria adhere more firmly to
surfaces and form more durable biofilm structures than under
low shear stress (4, 7). Both laminar and turbulent shear forces
allow bacteria to be closer to the surface and adhere more
easily than under static conditions (4). Biofilms sampled under
dynamic conditions appear to form a much thicker and denser
matrix compared to biofilm samples under static conditions.
As a result, it was clarified that the preferred sanitation agents
in the study are not adequate for biofilms developing under
dynamic conditions. Although some sanitation strategies
successfully removed cells and spores in biofilm structures that
developed under static conditions, the same results could not
be obtained for thermophilic biofilms sampled in the reactor.
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The efficacy of some of the sanitation procedures applied
at the point where biofilm formation is accelerated was
demonstrated by data from microbiological counts and
CLSM studies (5 h for Anoaxbacillus, 2 h for Geobacillus).
In addition, it became clear that biofilms developing under
dynamic conditions are difficult to eradicate and that sanitation
procedures recommended for the dairy industry may be
inadequate. Although the evaluated sanitation processes
were completely effective in the early stages when biofilm
production began, they were inadequate for mature biofilm
samples. Another important finding of the study was that the
physicochemical properties of the surfaces do not determine
the success of sanitation.
ACKNOWLEDGMENT
This research was supported by the Scientific and Technical
Research Council of Turkey (TÜBİTAK), project no. 116Z422.
The authors declare that they have no conflict of interest. This
article does not contain any data based on experiments performed
on animals.
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Food Protection Trends January/February
Food Protection Trends - January/February 2022

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