Salmonella detection · Step 2 – supplement for tetrathionate broth
Fluid Tetrathionate Broth Supplement
Two-component supplement (iodine–iodide solution and brilliant green solution) for completing tetrathionate broth base before use, for the selective enrichment of Salmonella.
- Iodine–iodide and brilliant green solutions
- For tetrathionate broth base
- Box of 2 × 5 vials · COLO code PRO7669
How the supplement is used
Iodine reacts with thiosulfate in the base to form tetrathionate, the selective agent of the broth; brilliant green suppresses Gram-positive bacteria. Both solutions are added aseptically to the cooled base just before use.
Technical data
| Use | 2 vials (iodine and brilliant green) per 100 mL of base |
| Storage | 2–8 °C; after opening keep in the box, protected from light |
| Shelf life | 3 years |
Applications and practical notes
This supplement completes tetrathionate broth base for the selective enrichment of Salmonella in food testing according to FDA BAM Chapter 5. Typical applications include:
- meat, poultry, eggs and egg products
- milk, dairy products and infant formula
- feed, spices and dry foods
- environmental swabs from the food production area
Working with Fluid Tetrathionate Broth Supplement: Add both solutions only to the cooled base and mix well before dispensing. The complete broth should be used on the day of preparation and should not be heated again.
Good practice with media and supplements: keep the bottle tightly closed in a cool, dry place, weigh the powder quickly to avoid moisture uptake, and use fresh distilled or deionised water. Check the pH of each new batch after preparation and before use, and label prepared media with the date. Performance of each lot can be verified with reference strains according to ISO 11133, the standard for the preparation, production, storage and performance testing of culture media.
About the Salmonella culture method: the reference method for Salmonella in the food chain, ISO 6579-1, has four steps: non-selective pre-enrichment, selective enrichment in two broths, plating on two selective agars and confirmation of typical colonies. The FDA BAM Chapter 5 follows the same principle with media adapted to different food types. Rapid tests and identification kits shorten the time to result, but positive screening results are usually confirmed by the culture method. COLO.Science offers products for every step, so that one supplier covers the whole procedure.
Complete sets from one supplier: COLO.Science supplies culture media, supplements, rapid tests, identification kits and QC strains as complete sets for the method you follow. Send us your sample types and standards, and we will prepare an offer with the matching products and documentation.
Fluid Tetrathionate Broth Supplement is supplied by COLO.Science in the pack sizes listed under Ordering information. For larger quantities, regular deliveries or method-specific sets that include Fluid Tetrathionate Broth Supplement, please send us a request.
Where tetrathionate broth fits in the Salmonella workflow
- Pre-enrichment – Buffered Peptone Water or Lactose Broth
- Selective enrichment – RV Broth and tetrathionate broth
- Selective isolation – XLD Agar plus a second selective or chromogenic agar
- Confirmation – TSI, Lysine Iron Agar, Urea Agar, latex and biochemical identification
See the complete Salmonella set in the Microbiology Catalogue →
Ordering information
| Product | COLO code | Pack |
|---|---|---|
| Fluid Tetrathionate Broth Supplement | PRO7669 | 2 × 5 vials |
| Fluid Tetrathionate Medium, dehydrated | PRO7483 | 500 g |
Product notice: preparation, storage conditions and shelf life are given on the label. Technical data on this page are for orientation; the label and the lot documentation apply. B2B prices are quoted net, excluding VAT.
Sales and technical support
COLO LabExperts
Polje ob Sotli 4, SI-3255, Slovenia
Quotations and technical support for culture media and microbiology products across our international sales territory. B2B prices are net, excluding VAT.
COLO.SCIENCE | MICROBIOLOGY SUPPORT
Need the complete set for your method?
Send the sample type, target organism and the standard you follow. COLO.Science will put together the media, supplements, QC strains and confirmation tests for the whole procedure.
