Listeria Selective Agar (PALCAM), 90mm Plate

Description

8058 – Listeria Selective Agar (PALCAM), 90mm Plate is a ready-to-use prepared plate supplied by SGL for selective detection and enumeration of Listeria species in food, environmental and hygiene samples. It is suitable for use in food and beverage; contract testing laboratories. This product is relevant to microbiology workflows described in ISO 11290 Listeria workflows; ISO 11133.

Listeria Selective Agar (PALCAM) is a medium for the isolation of Listeria monocytogenes from clinical material, milk and milk products, foodstuffs and heavily contaminated environmental samples.

PALCAM = Polymixin, Acriflavin, Lithium Chloride, Ceftazidime, Aesculin, Mannitol.

Food producers monitor pasteurised milk and dairy products for post-processing contamination by Listeria monocytogenes because the organism can grow at refrigeration temperatures and tolerate a broad pH range. L. monocytogenes can also occur in raw vegetables, poultry, fish, and fresh and processed meat. Sheep, cattle and goats may carry and shed the organism in their faeces.

Peptone supplies carbon, nitrogen, amino acids, vitamins and other nutrients that support microbial growth. Dextrose and starch provide additional nutrients and energy. Sodium chloride maintains osmotic balance.

Mannitol and phenol red form the medium’s differential system. Mannitol-fermenting organisms produce acid, causing phenol red to turn yellow. L. monocytogenes does not normally ferment mannitol, so the surrounding medium remains red.

Listeria species hydrolyse aesculin to glucose and esculetin. The esculetin reacts with ferric ammonium citrate to form a dark brown or black complex, producing characteristic black colonies and halos.

Lithium chloride, polymyxin B, acriflavine and ceftazidime suppress Gram-negative bacteria and many competing Gram-positive organisms, increasing the medium’s selectivity for Listeria species.

SGL manufactures and quality-controls the product to its internal specifications and in compliance with ISO 9001 (reference FM37824). A UKAS-accredited laboratory operating to ISO/IEC 17025 (accreditation number 4356) tests the product. At the customer’s request, the laboratory can also perform additional specification testing.

SKU: 8058