Microorganisms and performance criteria for selective enrichment media 'Fraser' used in Food chain microbiology according to ISO 11133.
ISO 11290-1 (2017) medium: Fraser
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1 Qualitative control of Productivity
- Use a quantitative reference material or test suspension with a known number of Listeria monocytogenes 4b and Escherichia coli and Enterococcus faecalis.
- Inoculate one tube of test medium with < 100 cells of target microorganisms and with >103 cells of non-target organisms.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Remove 10 µl and streak to a plate of specific medium for the target organism.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Growth of target microorganisms should reach "> 10 colonies on Agar Listeria according to Ottaviani and Agosti" with a characteristic reaction of: Blue green colonies with opaque halo.
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2 Qualitative control of Productivity opt
- Use a quantitative reference material or test suspension with a known number of Listeria monocytogenes 1/2a and Escherichia coli and Enterococcus faecalis.
- Inoculate one tube of test medium with < 100 cells of target microorganisms and with >103 cells of non-target organisms.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Remove 10 µl and streak to a plate of specific medium for the target organism.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Growth of target microorganisms should reach "> 10 colonies on Agar Listeria according to Ottaviani and Agosti" with a Characteristic reaction of: Blue green colonies with opaque halo.
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1 Qualitative control of Selectivity man
- Use a quantitative reference material or test suspension with a known number of Escherichia coli.
- Inoculate one tube of test medium with >103 cells of non-target organisms.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Remove 10 µl and streak to a plate of reference medium (TSA).
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Growth of non-target microorganisms should comply with the criteria: "Total inhibition (0) on TSA".
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2 Qualitative control of Selectivity man
- Use a quantitative reference material or test suspension with a known number of Enterococcus faecalis.
- Inoculate one tube of test medium with >103 cells of non-target organisms.
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Remove 10 µl and streak to a plate of reference medium (TSA).
- Incubate at (37 ± 1) °C for (48 ± 2) h.
- Growth of non-target microorganisms should comply with the criteria: "< 100 colonies on TSA".
Best Practice Fraser
Qualitative control of Selectivity of liquid medium, mixed culture
Control strain | WDCM number | Incubation | Criteria | Characteristic reaction | |
---|---|---|---|---|---|
Listeria monocytogenes 4b | (37 ± 1) °C for (48 ± 2) h | > 10 colonies on Agar Listeria according to Ottaviani and Agosti | Blue green colonies with opaque halo | ||
+ Escherichia coli | or | ||||
+ Enterococcus faecalis | or | ||||
The best practice for Qualitative control of Productivity for media control of 'Fraser' is based on the data displayed in this table according ISO 11133. |
Best Practice Fraser
Qualitative control of Selectivity of liquid medium, mixed culture
Control strain | WDCM number | Incubation | Criteria | Characteristic reaction | |
---|---|---|---|---|---|
Listeria monocytogenes 1/2a | (37 ± 1) °C for (48 ± 2) h | > 10 colonies on Agar Listeria according to Ottaviani and Agosti | Blue green colonies with opaque halo | ||
+ Escherichia coli | or | ||||
+ Enterococcus faecalis | or | ||||
The best practice for Qualitative control of Productivity for media control of 'Fraser' is based on the data displayed in this table according ISO 11133. |
Best Practice Fraser
Qualitative control of Selectivity of liquid medium, single culture
Control strain | WDCM number | Ref. media | Incubation | Criteria | Characteristic reaction |
---|---|---|---|---|---|
Escherichia coli | or | TSA | (37 ± 1) °C for (48 ± 2) h | Total inhibition (0) on TSA | No growth |
The best practice for Qualitative control of Selectivity for media control of 'Fraser' is based on the data displayed in this table according ISO 11133. |
Best Practice Fraser
Qualitative control of Selectivity of liquid medium, single culture
Control strain | WDCM number | Ref. media | Incubation | Criteria | Characteristic reaction |
---|---|---|---|---|---|
Enterococcus faecalis | or | TSA | (37 ± 1) °C for (48 ± 2) h | < 100 colonies on TSA | Growth |
The best practice for Qualitative control of Selectivity for media control of 'Fraser' is based on the data displayed in this table according ISO 11133. |