Palcam Agar – selective medium for Listeria isolation acc. to ISO11290
- Format: 500 g
- Code: TN1209
- Technology: Culture media and ISO confirmation tests
- Application: Food/Water microbiology
- Tag/Filter: Listeria
The PALCAM medium is used as a selective isolation medium for the detection of Listeria spp. in food products according to ISO 11290. Due to the combined action of lithium chloride and the selective supplement, this medium inhibits non-Listeria flora. On this medium, at 37°C, in 24 hours Listeria spp. form shiny gray or gray-green colonies of about 1 mm diameter, surrounded by a brown-black halo (esculin hydrolysis). Typical colonies with a diameter of approximately 2 mm develop in the agar 48 hours after streaking and incubation and present a central depression. PALCAM medium also contains a mixture of mannitol and phenol-red which makes possible to distinguish between colonies formed by Listeria spp. and colonies formed by non-inhibited esculin-positive Enterococcus. Unlike Listeria (other than L. grayi and L. murrayi), Enterococcus metabolizes mannitol. The acidification resulting from this metabolization causes the pH indicator to change (yellow haloes around the colonies). The medium is available as powder to be supplemented or ready-to-use in 90 mm Petri plates.
- Format: 500 g
- Code: TN1209
- Technology: Culture media and ISO confirmation tests
- Application: Food/Water microbiology
- Tag/Filter: Listeria
