Transcript Agricultural University of Athens

PILLAR 2: Control and intervention strategies
along the fork-to-farm chain to ensure beef safety
WP 13 and 25
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Experimental procedure

Beef fillets (100 g)
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Three pathogen bacteria
Listeria monocytogenes (mixture of 6 strains)
Salmonella ser. Typhimurium (mixture of 3 strains)
Escherichia coli 0157:H7 (mixture of 3 strains)
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Three levels of inoculation
High level (107 CFU/g)
Medium level (105 CFU/g)
Low level (103 CFU/g)
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Meat mincing machine
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Two replications (from different beef batches) with three
samples each
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o
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Experimental procedure
7th Beef fillet - Non inoculated
6th Beef fillet - Non inoculated
5th Beef fillet - Non inoculated
4th Beef fillet - Non inoculated
3rd Beef fillet - Non inoculated
2nd Beef fillet - Non inoculated
1st Beef fillet - Inoculated
1st – 7th
sample
Contaminated
Meat mincing machine
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Conclusions till now…

All the non-inoculated samples were contaminated from meat
mincing machine, for L. monocytogenes at all inoculum levels
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A 2-log decrease was observed from 1st inoculated sample till
7th non-inoculated for the pathogen tested

In general, L. monocytogenes, Salm. ser. Typhimurium and E.
coli may contaminate sequential meat samples through meat
mincing machine and consist a high risk in processing
industry
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Conclusions till now…
8.00
7.00
LogCFU/g
6.00
5.00
4.00
3.00
2.00
1.00
0.00
0
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Samples
L. monocytogenes contamination from meat mincing machine to 7 sequential
beef samples for three initial inoculum levels
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Future work (…to be done the next 1-2
months)

To finish with all the other pathogen bacteria
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To replicate the experiment with different meat batch
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Future work (…to be done the next 5-6
months)
Control of biofilm contamination at non-inoculated beef fillets
(using microbiological and molecular techniques)
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Three pathogen bacteria
Listeria monocytogenes (mixture of 6 strains)
Salmonella ser. Typhimurium (mixture of 3 strains)
Escherichia coli 0157:H7 (mixture of 3 strains)
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Biofilm formation of these pathogens
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Biofilm contamination of non-inoculated beef fillets
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o
o
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens
PILLAR 1 and 2, WP13-wp25
Thank you
Laboratory of Microbiology &
Biotechnology of Foods
Agricultural University of Athens