Orange-serum Agar (catalogue No. 75405) is a non-sterile dehydrated culture medium powder for microbiological applications. It contains agar, casein peptone, dipotassium hydrogen phosphate, glucose, orange extract and yeast extract, formulated at low pH to promote selective growth of aciduric bacteria, yeasts and molds in fruit juices, concentrates and other acidic matrices. This medium is suitable for quality control in food, beverage and environmental laboratories.
Orange-serum Agar, catalogue No. 75405 (NutriSelect® Basic) is a dehydrated culture medium supplied by MilliporeSigma / Merck, formulated for microbiological culture and enumeration of acid-tolerant spoilage microorganisms. It combines agar with nutrient sources such as casein peptone, yeast extract and glucose, along with orange extract to establish a low pH medium. The medium is provided in powdered form and must be rehydrated and sterilized prior to use. It supports cultivation of yeasts, molds and aciduric bacteria frequently encountered in fruit juices, concentrates and other acidic food or beverage samples. :contentReference[oaicite:3]{index=3}
Advantages
- Selective low pH medium promoting growth of aciduric microbes.
- NutriSelect® Basic formulation for routine quality control microbiology.
- Powder form for convenient preparation in laboratory workflows.
- Supports diverse microbial groups including yeasts and molds.
- Applicable to food, beverage and environmental testing.
Technical specifications
| Medium type | Dehydrated culture medium powder |
| Product form | Powder |
| Sterility | Non-sterile |
| Composition | Agar, casein peptone, dipotassium hydrogen phosphate, D(+)-glucose, orange extract, yeast extract |
| Final pH (25 °C) | ≈ 5.5 ± 0.2 |
| Typical applications | Microbiological culture and enumeration in food, beverage and environmental samples |
| Technique | Standard plating and incubation |
| Storage | Store powder in a cool, dry place |
| Brand | Merck |
