Lactose broth is used for the performance and confirmation of the Presumptive Test for coliforms in water and dairy samples. This medium is also frequently used as a pre-enrichment medium when testing foods, water samples and dairy products for Salmonella spp.
Beef extract and gelatin peptone provide the required carbon, nitrogen and vitamins in this medium. Lactose is a fermentable carbohydrate. Fermentation of lactose is detected by the production of gas
Lactose Broth
Additional Information
| Shelf Life (days) | |
|---|---|
| Storage Temp (°C) | |
| Dehydrated Medium Appearance | |
| Prepared Medium Appearance | |
| Dehydrated Medium Colour | |
| Prepared Medium Colour | |
| Dehydrated PH | |
| Prepared PH | |
| Recommended Incubation |
Product Description
| Organisms | Ref. No | Result |
| Escherichia coli | NCTC 12241 | Turbid growth, gas production |
Formula*
| g/L | |
| Beef extract | 3.0 |
| Gelatin peptone | 5.0 |
| Lactose | 5.0 |
| Total | 13.0 |
| *Adjusted/supplemented as required to meet performance requirements | |
Preparation
Suspend 13g of the medium in one litre of deionised / purified water. Allow the medium to soak whilst mixing for 10 minutes. Sterilise at 121°C for 15 minutes with frequent stirring to completely dissolve the medium. Cool to 45-50°C and dispense into appropriate sterile containers.