
VRBA Agar – Violet Red Bile Agar for Coliform Enumeration
Premium Violet Red Bile Agar (VRBA) – Gold Standard for Coliform Detection & Enumeration
Precisely identify and quantify coliform bacteria with our selective VRBA medium – the definitive choice for food safety testing, water quality analysis, and environmental monitoring. Formulated with bile salts and dual chromogens for superior differentiation of lactose-fermenting bacteria per ISO 4832, FDA BAM, and APHA standards.
Critical Applications:
✔️ Food Safety Testing – Dairy/meat coliform enumeration
✔️ Water Potability Analysis – Total coliform counts
✔️ Environmental Monitoring – Processing surface contamination
✔️ Pharmaceutical QC – Purified water system validation
✔️ Beverage Industry – Finished product release testing
Chromogenic Selection System (per liter):
| Component | Quantity | Function |
|—————————-|———-|——————————|
| High-Quality Peptone | 7.0g | Nitrogen Source |
| Yeast Extract | 3.0g | Vitamin Complex |
| Lactose | 10.0g | Fermentation Substrate* |
| Bile Salts | 1.5g | Gram-positive Inhibition |
| Sodium Chloride | 5.0g | Osmotic Balance |
| Neutral Red | 0.03g | Acid Production Indicator |
| Crystal Violet | 0.002g | Selective Agent |
| Purified Agar | 15.0g | Optimal Gel Formation |
pH: 7.4 ± 0.1 (25°C)
*Lactose fermenters: Red-purple colonies with bile precipitate halos
Validated Preparation Protocol:
Dissolve 41.5g in 1L purified water
Boil 1 minute with constant stirring
Cool to 45-50°C (DO NOT AUTOCLAVE)
Pour Plates immediately – 4mm thickness recommended
Solidify: Allow plates to set for 20 minutes