HALF FRASER BROTH AND FRASER BROTH

Pre-enrichment and Selective Enrichment

Application procedure for Listeria monocytogenes analysis:

Two enrichment procedures allow for more precise analysis than a single enrichment procedure.

Single enrichment procedure:

10ml sample is weighed into 90ml Half Fraser Broth. Incubate at 30C for 18-24 hours.

Inoculation is done on Chromogenic Listeria medium from Half Fraser Broth.

Incubate at 37°C for 24 hours. The resulting green, light colored colonies are considered as L. monocytogenes.

Green colonies with no surrounding zones are other Listeria species.

Two enrichment procedures: Weigh 10ml sample into 90ml Half Fraser Broth. Incubate at 30C for 18-24 hours.

0.1 m from Half Fraser Broth| taken and added to 9 ml of Fraser Broth. Incubate at 30C for 18-24 hours.

Inoculation is made on Chromogenic Listeria medium from Fraser Broth.

Incubate at 37C for 24 hours.

Colonies with green surrounding and light colored zones are considered as L. monocytogenes. Green colonies without zones around other Listeria

are types.

LISTERIA ANALYSIS ENHANCEMENT MEDIA

HALF FRASER BROTH AND FRASER BROTH

They are enrichment media used in the two-stage analysis method of Listeria monocytogenes.

The way of use is as described above under the heading "Detection of Listeria monooytogenes".

It is prepared in 9ml, 90ml and 225ml sizes according to the need and type of analysis.