Violet Red Bile Glucose Agar 500Gr | Oxoid CM0485B

Violet Red Bile Glucose Agar 500Gr | Oxoid CM0485B A glucose-containing selective medium for the detection and enumeration of Enterobacteriaceae in food products. Directions Suspend 38.5g in 1 litre of distilled water. Bring to the boil. Continue to boil for 2 minutes or for the minimum time necessary to dissolve completely and ensure that there are no remaining flecks of unmelted agar. No further sterilisation is necessary or desirable. Mix well and dispense into tubes or dishes. Description Results from tests that may be applied to water to detect coli-aerogenes organisms as possible indicators of faecal contamination possess far less significance when applied to raw foods. In the examination of foodstuffs, detection of a more defined group of organisms, the Enterobacteriaceae, that ferment glucose to produce acid and/or gas has been recommended1,2. In addition to coliforms this group includes salmonellae and shigellae, which do not ferment lactose, and enterotoxigenic Escherichia coli. It also contains organisms, such as Klebsiella and Citrobacter, which are more resistant to heat than coliforms and are therefore better indicators of failure of processes that use minimal heat. The difficulties of measuring the total Enterobacteriaceae content of foodstuffs have been studied by Mossel et al.3, who showed that the addition of glucose to an existing medium for the detection of coliforms improves the performance. They added 10g per litre of glucose to crystal violet neutral red bile lactose agar (Violet Red Bile Agar CM0107), and named the modified formulation MacConkey Glucose Agar. Further work by Mossel et al.4,5 showed that the lactose could be omitted resulting in the formulation of Violet Red Bile Glucose Agar. The continued inclusion of lactose would not provide test results leading to more accurate identification. Exclusion of lactose renders the medium more economical to make as less weight is required per litre.