Usage of Compact Dry CF is a simple and safe test procedure for determination and quantification of coliform bacteria in foods, cosmetics or raw materials – as well as pharmaceutical raw materials. The ready-to-use plates consist of a special 50 mm diameter petri dish containing a detection specific nutrient pad.
The term “coliform bacteria” doesn’t describe a taxonomical group beyond the eubacteria. It actually is more a summary of some genera from the family of enterobacteria. Their common biochemical characteristics are positive lactose reaction as well as negative oxidase reaction. Coliform bacteria are considered to be indicators for fecal contaminations. Enumeration of coliform bacteria in food samples gives an overview on the hygienic status of raw materials and production as well.
The nutrient medium of Compact Dry CF contains the chromogenic enzyme substrate X-Gal. Thus colonies of coliform bacteria show a characteristic blue or blue-green coloration while growing on the nutrient pad. Growth of other bacterial species is widely inhibited. Colonies of bacteria which are able to grow on Compact Dry CF (e.g. Pseudomonas spp.) will appear colorless. Counting all blue colonies on the nutrient plates allows the determination of total coliform numbers in the sample.
The ready-to-use, chromogenic Compact Dry plates are suitable for in-process controls as well as controls of finished products. With the optional additional product Promedia ST-25 swab test (Z0302) or Compact Dry Swab (ZCS1002953) Compact Dry plates may also be used for surface sampling and therefore applied for quantitative hygiene monitoring even at surfaces which are difficult to reach.
- Compact Dry CF is therefore an extremely easy-to-use method and also convincing due to the high time saving; a confirmation test is also not necessary.
- MicroVal - Certificate No. 2008LR03 (MV0806-003LR)
- NordVal - Certificate No. 035
- AOAC-RI - Certificate No. 110401
|Art. No.||HS8791 / HS8792|
|Test format||HS8791: 100 nutrient plates, |
HS8792: 40 nutrient plates,
four plates are packed in one aluminum bag.
|Sample preparation||Viable count in water or liquid foodstuff, in solid foodstuff or in swab tests.|
|Incubation time||24 ± 2 h at 37 ± 1 °C (MicroVal, NordVal) or 35 ± 2 °C (AOAC)|
Coliform bacteria = blue / blue green colonies