Description
The substitution of glucose in place of lactose in Violet Red Bile Glucose Agar results in a positive reaction – production of acid with or without gas with all Enterobacteriaceae.
This formula is more appropriate in the testing of raw food than Violet Red Bile Agar because the broader spectrum testing include such organisms as Salmonella sp. and Shigella sp., which are non-lactose fermenters.
Klebsiella and Citrobacter which are better indicators of process failure than coliforms are also adequately screened. Glucose fermenting organisms such as Aeromonas sp. and Yersinia sp. may grow poorly.
Mossel recommended the variation in formula when the use of this medium became popular in the testing of foodstuffs. Initially he added glucose to the Violet Red Bile Agar already in use for water testing and demonstrated improved detection of Enterobacteriaceae.
