ISO 16654 (2001) medium: CT-SMAC

Media control Food and animal feeding stuffs

Microorganisms and performance criteria for selective isolation media 'CT-SMAC' used in Food and animal feeding stuffs microbiology according to ISO 11133.

  • Qualitative control of Productivity

  • Best Practice CT-SMAC

    Qualitative control of Productivity solid medium

    1. Use a reference material or test suspension with a known number of Escherichia coli O157:H7.
    2. The volume used for testing should contain 103 to 104 cfu for qualitative tests of plate media.
    3. Streak the test microorganism (Escherichia coli O157:H7) on the media under test (CT-SMAC) to obtain discrete colonies.
    4. Incubate at (37 ± 1) °C for (21 ± 3) h.
    5. Asses the amount of growth as, 0 for no growth, 1 for weak growth or 2 for good growth.
    6. For this medium (CT-SMAC) and standard (ISO 16654) combination the criteria is: "Good growth (2)".
    7. The Characterictic reaction is: Transparent colonies with a pale yellowish-brown appearance and a diameter ~1 mm.

    Control strain WDCM number Incubation Criteria Characteristic reaction
    Escherichia coli O157:H7 (37 ± 1) °C for (21 ± 3) h Good growth (2) Transparent colonies with a pale yellowish-brown appearance and a diameter ~1 mm
    The best practice for Qualitative control of Productivity for media control of 'CT-SMAC' is based on the data displayed in this table according ISO 11133.
  • 1 Qualitative control of Selectivity man

  • Best Practice CT-SMAC

    Qualitative control of Selectivity solid medium

    1. Use a reference material or test suspension with a known number of Staphylococcus aureus.
    2. Streak the test strain (Staphylococcus aureus) as a single line on the media under test (CT-SMAC).
    3. Use a 1 µl loop in case of a concentration of at least 10000 cfu or a 10 µl loop in case of a concentration between 1000 and 10000 cfu.
    4. Incubate at (37 ± 1) °C for (21 ± 3) h.
    5. Asses the amount of growth as, 0 for no growth, 1 for weak growth or 2 for good growth.
    6. For this medium (CT-SMAC) and standard (ISO 16654) combination the criteria is: "Total inhibition (0).

    Control strain WDCM number Ref. media Incubation Criteria Characteristic reaction
    Staphylococcus aureus or (37 ± 1) °C for (21 ± 3) h Total inhibition (0) No growth
    The best practice for Qualitative control of Selectivity for media control of 'CT-SMAC' is based on the data displayed in this table according ISO 11133.
  • 2 Qualitative control of Selectivity man

  • Best Practice CT-SMAC

    Qualitative control of Selectivity solid medium

    1. Use a reference material or test suspension with a known number of Escherichia coli.
    2. Streak the test strain (Escherichia coli) as a single line on the media under test (CT-SMAC).
    3. Use a 1 µl loop in case of a concentration of at least 10000 cfu or a 10 µl loop in case of a concentration between 1000 and 10000 cfu.
    4. Incubate at (37 ± 1) °C for (21 ± 3) h.
    5. Asses the amount of growth as, 0 for no growth, 1 for weak growth or 2 for good growth.
    6. For this medium (CT-SMAC) and standard (ISO 16654) combination the criteria is: "Partial inhibition (1)".

    Control strain WDCM number Ref. media Incubation Criteria Characteristic reaction
    Escherichia coli or (37 ± 1) °C for (21 ± 3) h Partial inhibition (1) Growth of some pink colonies
    The best practice for Qualitative control of Selectivity for media control of 'CT-SMAC' is based on the data displayed in this table according ISO 11133.