Recently, the European Food Safety Authority proposed that each EU
member state should conduct a survey of Listeria monocytogenes in soft
cheeses for sale in retail outlets. Hence, retail samples of soft
cheeses in Greece (n = 137) were analyzed qualitatively and
quantitatively for both L. monocytogenes and other Listeria spp., as
well as for pH and a (w). None of the cheeses analyzed were found
positive for L. monocytogenes (0%; 95% confidence interval (CI) =
0.0-2.2%). Three samples (2.2%; 95% CI = 0.5-6.3%) were positive for
other Listeria spp., with populations ranging from < 5 to 4.5 x 10(2)
CFU g(-1). Although soft cheeses are regarded as foods that permit the
proliferation of L. monocytogenes, 15.4% of the whey cheeses tested had
pH values a parts per thousand currency sign4.4 and 29% of the interior
mold-ripened cheeses had a (w) values a parts per thousand currency
sign0.92. Such low pH values for whey cheeses are unexpected, based on
their manufacturing technology, and are associated with lower quality
and reduced shelf life. Nonetheless, in the present survey, the
percentage of whey cheeses in the Greek retail market exhibiting
unusually low pH values or testing positive for Listeria spp. was much
lower compared to the respective percentages reported from studies
conducted in the 1990s. The absence of L. monocytogenes in the tested
cheeses undoubtedly constitutes an encouraging result with respect to
the safety of soft cheeses in the Greek retail market. However, the
presence of other Listeria spp. in three of the tested samples implies
that L. monocytogenes would, most likely, also be present in the
food-processing or retail-handling environments of these products.
Therefore, cheese manufacturers and retail handlers should continue or
even intensify the application of all necessary measures with the aim of
preventing food contamination
