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Demi-Fraser Broth Base (Half Fraser Broth) for Listeria Enrichment | AS-1194
$45.00 AUD
AuSaMicS Life Science • Listeria Enrichment Media
Demi-Fraser Broth Base (Half Fraser Broth)
Primary Selective Enrichment Medium for Listeria spp.
Selective enrichment broth for the primary recovery of Listeria species, especially Listeria monocytogenes, from food and environmental samples. Half Fraser Broth is designed to recover stressed or injured cells while maintaining sufficient selectivity against background flora, making it the standard first-step enrichment medium in Listeria testing workflows.
AS-1194
🧪 Primary Enrichment Broth
✓ ISO Listeria Workflow
🔬 Esculin Blackening
Use: Primary Listeria enrichment
Readout: Brown to black darkening
Follow-up: Oxford / ALOA / PALCAM plating
Recommended Shopify Setup
Best Product Title:
Demi-Fraser Broth Base (Half Fraser Broth) for Listeria Enrichment | AS-1194
Demi-Fraser Broth Base (Half Fraser Broth) for Listeria Enrichment | AS-1194
Meta Title:
Half Fraser Broth for Listeria | AS-1194 | AuSaMicS
Half Fraser Broth for Listeria | AS-1194 | AuSaMicS
Meta Description:
Demi-Fraser Broth Base for primary enrichment of Listeria from food and environmental samples. Ideal for ISO 11290 workflows and Listeria recovery.
Demi-Fraser Broth Base for primary enrichment of Listeria from food and environmental samples. Ideal for ISO 11290 workflows and Listeria recovery.
Suggested Pack Sizes
100 g • 500 g • 1 kg • 5 kg
🧪 Complete Formulation & Selective Principle
📋 Typical Composition (per Liter)
Final pH: 7.2 ± 0.2 at 25°C
⚗️ Functional Design
Reduced-Inhibitor Primary Enrichment
Designed to recover stressed or injured Listeria cells before stronger secondary selection
Designed to recover stressed or injured Listeria cells before stronger secondary selection
Esculin Blackening System
Positive enrichment darkens as Listeria hydrolyzes esculin
Positive enrichment darkens as Listeria hydrolyzes esculin
Workflow-Compatible Base
Ideal first step before Fraser Broth, Oxford Agar, or ALOA plating
Ideal first step before Fraser Broth, Oxford Agar, or ALOA plating
Why Demi-Fraser Broth? It is the key primary enrichment step when maximum Listeria recovery is needed from difficult food and environmental matrices, especially where cells may be sublethally damaged.
Complete Listeria Workflow Portfolio
Strategic Medium Selection for Listeria Recovery
✅ Demi-Fraser Advantages
- ✓ Better Recovery of Injured Cells: Reduced inhibitor level supports stressed Listeria
- ✓ Standard First Step: Fits mainstream ISO-style Listeria workflows
- ✓ Visible Presumptive Signal: Esculin blackening helps rapid screening
- ✓ Broad Sample Suitability: Food, swabs, dairy, meats, vegetables, surfaces
- ✓ Excellent Sales Positioning: Essential medium in every serious Listeria workflow
⚠️ Method Considerations
- ▲ Not a Final Confirmation Medium: Positive broths must be subcultured and confirmed
- ▲ Supplement Handling Matters: Ferric ammonium citrate and selective supplements must be added correctly
- ▲ Short Ready-to-Use Stability: Supplemented broth is best used fresh
- ▲ Some Competing Esculin-Positive Flora Exist: Follow-up plating remains essential
🎯 Best-Fit Applications
- ◆ Food Safety Labs: Routine Listeria detection in foods and ingredients
- ◆ Environmental Monitoring: Swabs, drains, and food plant surfaces
- ◆ Dairy and RTE Programs: Samples with stressed or low-level contamination
- ◆ Regulatory and Research Labs: ISO-oriented Listeria workflows
📊 Typical Interpretation
💰 Recommended Pack Sizes & Market-Beating Pricing
Recommended pricing position: sell this as an essential ISO-style workflow medium, priced below major multinational brands but clearly above low-end commodity suppliers on technical credibility and documentation.
📋 Technical Specifications
| Catalogue Number | AS-1194 |
| Medium Type | Primary selective enrichment broth |
| Target Organisms | Listeria monocytogenes and other Listeria spp. |
| Reconstitution | Approx. 55–57.9 g/L depending on formulation |
| Final pH | 7.2 ± 0.2 at 25°C |
| Indicator System | Esculin + ferric ammonium citrate |
| Selective Agents | Lithium chloride, nalidixic acid, acriflavine |
| Incubation | 30°C for 24 h typical primary enrichment |
| Supplement Addition | Ferric ammonium citrate after sterilization |
| Prepared Broth Use | Best used fresh after supplementation |
🧫 Primary Applications
- ✓ Primary enrichment of food and environmental samples for Listeria testing
- ✓ Recovery of stressed or low-level Listeria contamination
- ✓ First-step enrichment before Fraser Broth and selective plating
- ✓ Food safety, dairy, meat, ready-to-eat, and environmental monitoring workflows
⚗️ Preparation Protocol
- 1. Suspend the dehydrated base in purified water.
- 2. Heat with agitation until completely dissolved.
- 3. Sterilize at 121°C for 15 minutes.
- 4. Cool and aseptically add ferric ammonium citrate supplement.
- 5. Inoculate sample homogenate and incubate for primary enrichment before subculture.
📦 Storage & Intended Use
Dehydrated medium: Store tightly closed in a cool, dry place.
Prepared supplemented broth: Best used fresh; refrigerated short-term only if necessary.
Workflow note: Positive enrichments should be subcultured and confirmed by selective agar and standard laboratory identification methods.
Notice: For food and environmental microbiology use only.
AuSaMicS Life Science: Professional microbiology media for food safety, environmental monitoring, quality control, research, and standardized pathogen detection workflows. Product information is provided for laboratory and technical evaluation purposes only.