Violet Red Bile Agar
Violet Red Bile Agar is used for enumerating coliform organisms in dairy products.
Principles
Violet Red Bile Agar contains peptone to provide carbon and nitrogen sources for general growth requirements. Yeast extract supplies B-complex vitamins which stimulate bacterial growth. Bile salts and crystal violet inhibit most gram-positive microorganisms. Lactose is the carbohydrate source and neutral red is the pH indicator. Agar is the solidifying agent.
Violet Red Bile Agar (VRBA) is the gold-standard medium for coliform enumeration in dairy, milk, and milk products. Bile salts and crystal violet inhibit gram-positive bacteria while neutral red indicator reveals lactose fermentation. Red/pink colonies indicate coliform presence. Used in raw milk, pasteurized milk, and related food product testing. Available from three trusted manufacturers in 500g and 2kg sizes. Sign in to your account or contact your sales rep for organizational pricing.
Frequently Asked Questions
Why do colonies appear red or pink?
Lactose-fermenting bacteria produce acid that turns the neutral red indicator red/pink.
Is VRBA specific for E. coli?
VRBA detects coliforms broadly (E. coli, Klebsiella, Enterobacter). Confirmation testing differentiates species.
What sample types can be tested?
Raw milk, pasteurized milk, ultra-pasteurized milk, milk products, and food and environmental swabs.
| Item No. | Alt. Part No. | Brand Name | Mfr. Item No. | Packaging | Unit of Measure | Your Cost | Purchase |
|---|---|---|---|---|---|---|---|
|
Violet Red Bile Agar
3097-81
|
EF0012-17 | Difco | 211695 | 500 gram | Each |
$161.82
|
|
|
Violet Red Bile Agar
3097-84
|
Difco | 211687 | 2 kg | Each |
$719.84
|
||
|
Violet Red Bile Agar
3115-70
|
Criterion | C7261 | 500 gram | Each |
$73.38
|
||
|
Violet Red Bile Agar
3115-80
|
Criterion | C7262 | 2 kg | Each |
$271.13
|
||
|
Violet Red Bile Agar
3116-34
|
Alpha Biosciences | V22-100 | 500 gram | Each |
$66.65
|
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|
Violet Red Bile Agar
3116-35
|
Alpha Biosciences | V22-100 | 2 kg | Each |
$245.34
|
