Formulated to ISO 6887-1, Maximum Recovery Diluent (MRD) is a diluent designed to maintain organisms by protecting the cells from unnecessary physiological shock that may occur using other aqueous solutions. MRD is used extensively in food and environmental testing.
The low level of peptone provides a protective effect but does not allow for multiplication during the short residence time in the diluent, 45 minutes. The sodium chloride prevents osmotic shock as the sample is initially diluted.
| Shelf Life (days) | |
|---|---|
| Storage Temp (°C) | |
| Dehydrated Medium Appearance | |
| Prepared Medium Appearance | |
| Dehydrated Medium Colour | |
| Prepared Medium Colour | |
| Dehydrated PH | |
| Prepared PH |
| Organisms | Ref. No | Result |
| Escherichia coli (maintenance test) | NCTC 12241 | Stable Viability * |
| Staphylococcus aureus (maintenance test) | NCTC 12981 | Stable Viability * |
| *Stable viability = ≤ ± 30% difference compared to original count after incubation for 45 minutes at 20-25° | ||
| g/L | |
| Peptone | 1.0 |
| Sodium chloride | 8.5 |
| Total | 9.5 |
| *Adjusted/supplemented as required to meet performance requirements | |
Suspend 9.5g of the medium in one litre of deionised / purified water. Allow the medium to dissolve whilst mixing for 10 minutes. Dispense the required volume into the final containers and sterilise at 121°C for 15 minutes.