VRBGA ISO (500 gram)
LV002-02014
Productomschrijving
Oxoid VRBGA (ISO).
Various groups of bacteria or individual species are used to provide evidence of poor hygiene, inadequate processing or post-processing contamination of foods. Some bacteria, such as Escherichia coli, are present in the gastrointestinal tract of many animals, including humans, so their presence can be used to indicate potential faecal contamination.
One of the most common groups of bacteria employed as indicator organisms by the food industry are the coliforms, which can be regarded as a subgroup within the Enterobacteriaceae. However, in an attempt to improve assessment of food safety and quality by the food industry, there has been a gradual move towards testing for total Enterobacteriaceae rather than limiting testing to coliforms. In processed foods, particularly foods subjected to heat treatment, these organisms can provide a reliable indication of process failure, under-processing or post-processing contamination.
Mossel et al3 modified Violet Red Bile Lactose Agar by adding glucose to improve recovery of all Enterobacteriaceae. Later work by Mossel and Cowell4,5 demonstrated that lactose could be omitted, resulting in the formulation known as VRBGA.
Enterobacteriaceae rapidly ferment glucose and so reduce the pH of the medium, which produces purple/pink coloured colonies due to the inclusion of the neutral red indicator and crystal violet in the medium. These colonies are usually surrounded by purple halos of precipitated bile salts. Crystal violet and bile salts inhibit the growth of Gram-positive flora.
Specificaties
| Inhoudsgegevens | |
|---|---|
| Inhoud in gram | 500 |
| Productspecifiek | |
|---|---|
| Mediatype | Violet Red Bile Glucose Agar (ISO) |
| Vorm | Poeder |