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Pillar 2:
Control and intervention strategies which can be implemented along the
fork to farm chain to ensure safe beef
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Workpackage 2.2: Processing strategies
- Progress during the last 6 months -
Objectives-AUA Objectives-AUA
Task 2.2.2: Safety of marinades
Evaluation of the effect of different traditional
marinades to control Salmonella Typhimurium in
beef fillets
Evaluation of the effect of wine-based marinades
to control Salmonella Typhimurium and to extend
the shelf life of meat
Monitoring the survival of S. Typhimurium strains
in marinated beef fillets
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Task 2.2.2: Safety of marinades
Evaluation of the effect of different
traditional marinades to control Salmonella
Typhimurium in beef fillets
Evaluation of the effect of different traditional marinades to control Evaluation of the effect of different traditional marinades to control S. S. Typhimurium in Typhimurium in beef filletsbeef fillets
Evaluation of the effect of different traditional marinades to control Evaluation of the effect of different traditional marinades to control S. S. Typhimurium in Typhimurium in beef filletsbeef fillets
Experimental procedures
Product: beef fillets (non sterilized)
Inoculum: A 3-strain cocktail of acid or non-acid adapted S. Typhimurium DT 193: Human isolate, epidemic, multi drug resistance
4/74: Calf bowel DSM 554: Unknown origin
Marinades: i) Olive oil ii) Wine iii) Olive Oil : wine (1:2) iv) Olive oil supplemented with 0.1% thyme oil v) Olive oil supplemented with 0.3% thyme oil vi) Wine supplemented with 0.1% thyme oil vii) Wine supplemented with 0.3% thyme oil viii) Olive oil : Wine (1:2) supplemented with 0.1% thyme oil ix) Olive oil : Wine (1:2) supplemented with 0.3% thyme oil
Marination time: 4, 12, 24 h, at 4 °C
Storage: air, at 15 °C, 96 h
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of different traditional marinades to control Evaluation of the effect of different traditional marinades to control S. S. Typhimurium in Typhimurium in beef filletsbeef fillets
Results
2
2.5
3
3.5
4
4.5
0 4 8 12 16 20 24
marination time (hrs)
Log
CFU
/g
olive oil
wine
olive oil & wine
olive oil & 0.3% EO thyme
wine & 0.3% EO thyme
olive oil & wine & 0.3% EO thyme
Survival of S. Typhimurium as affected by the type and the duration of marination
Survival of S. Typhimurium was affected by type & duration of marination
•immersion of fillets into the marinades for 12 or 24 h resulted to higher decrease of S. Typhimurium compared to 4 h
•immersion of inoculated fillets into wine resulted into higher decrease of S. Typhimurium compared to the other two marinades (oil, oil & wine)
•Adaptation of cells to acid as well as the addition of EO did not affect the survival of S. Typhimurium
MOST EFFECTIVE DURATION:
12 h
0
1
2
3
4
5
6
7
8
0 10 20 30 40 50 60 70 80 90 100
marination & storage (hrs)
Lo
g C
FU
/g
olive oil wine
olive oil & wine olive oil & 0.3% EO thyme
wine & 0.3% EO thyme olive oil & wine & 0.3% EO
•Survival of S. Typhimurium during storage was significantly affected by the type of marinade as well as the addition of EO of thyme in the marinade
• the combination of wine and 0.3% EO of thyme resulted into the higher destruction of S. Typhimurium (bellow detection limit) compared to the other marinades
“wine plus 0.3% thyme oil” was the most effective marinade in reducingS.
Typhimurium
Survival of S. Typhimurium as affected by the type of marinades and the addition of EO during storage
Evaluation of the effect of different traditional marinades to control Evaluation of the effect of different traditional marinades to control S. S. Typhimurium in Typhimurium in beef filletsbeef fillets
Task 2.2.2: Safety of marinades
Evaluation of the effect of wine based
marinades to control Salmonella Typhimurium
and to extend the shelf life of meat
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Experimental procedures
Product: Beef fillets (non sterilized)
Inoculum: A 3-strain cocktail of acid and non-acid adapted S. Typhimurium cells (DSM 554, DT 193 and 4/74) (ca. 104 cells/g)
Marinades: i) Wine ii) Wine supplemented with 0.3% thyme oil
Storage comditions: i) air, ii) MAP (25% CO2 and 75% air), at 5°C
Sampling and sensory evaluation: 12 h, 2, 4, 7, 11, 14 and 19 d
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Control
Wine Wine+0.3% EO
1) Air, non-acidadapted cells
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Control
Wine
4.50
5.00
5.50
6.00
6.50
7.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
0 3 6 9 12 15 18 21TVC-NA-Air Pseudomonas -NA-Air LAB-NA-Air
Salmonella-NA-Air pH- NA-Air
Wine+0.3% EO
2) Air, acidadapted cells
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Control
Wine Wine+0.3% EO
3) MAP, non-acidadapted cells
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Control
Wine Wine+0.3% EO
4) MAP, acidadapted cells
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
0 2 4 6 8 10 12 14 16 18 20
LOG
cfu/
g
days
AIR
Control-NA Control-AA Wine-NA
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
0 2 4 6 8 10 12 14 16 18 20
LOG
cfu/
g
days
MAP
Control-NA Control-AAWine-NA Wine-AAWine+0.3%Thyme-NA Wine+0.3%Thyme-AA
Effect of marination on the behavior of Salmonella Typhimurium inoculated on beef slices, stored under aerobic and MAP atmosphere
Conclusions
•Marination significantly reduced the levels of S. Typhimurium and the background flora of beef compared to the control (non-marinated)
•The survival of S. Typhimurium and microbial association was significantly affected by the addition of EO of thyme in marinade
•Not important differences were detected between acid and non-acid adapted S. Typhimurium during the time-course
Evaluation of the effect of wine-based marinades to control S. Typhimurium and to extend the shelf life of meat
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Task 2.2.2: Safety of marinades
Monitoring the survival of S. Typhimurium strains
in marinated beef fillets
Monitoring the survival of S. Typhimurium in marinated beef fillets
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
Monitoring the survival of S. Typhimurium in marinated beef fillets
Experimental procedure
Strains: S. Typhimurium DSM 554, DT 193 and 4/74 (acid and non-acid adapted)
Marinades: i) Wine, ii) Wine supplemented with 0.3% thyme oil
Storage comditions: i) air, ii) MAP (25% CO2 and 75% air), at 5°C
Sampling: 0.5, 7, 14 d
Strain typing: by PFGE
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Lanes 2, 5, 9-11: DSM 554; Lanes 7, 13: DT 193; Lanes 3, 4, 6, 8, 12, 14: 4/74
Laboratory of Microbiology and Biotechnology of Foods Agricultural University of Athens
0%
20%
40%
60%
80%
100%
AIR-NA
4|74
DT 193
DSM 554
12h 7d 14d
0
20
40
60
80
100
MAP-NA
4|74
DT 193
DSM 554
12h 7d 14d
0
20
40
60
80
100
AIR-AA
4|74
DT 193
DSM 554
12h 7d 14d
0
20
40
60
80
100
MAP-AA
4|74
DT 193
DSM 554
12h 7d 14d
•Monitoring of S. Typhimurium DSM 554, DT 193 & 4/74 during storage of fillets revealed similar strain distribution in different storage conditions throughout time-course
•Importantly, the epidemic multi-drug resistant DT 193 could compete other strains, like 4/74 originating from calf bowel
Monitoring the survival of S. Typhimurium in marinated beef fillets
