Microbiology Methods for ERP Review 3-2020

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and incubate at 42 ± 1°C for 22–26 h. (p) Environmental samples . ― Add enough BPW to cover the sampling device (ex. 10 mL for a swab and 100 mL for a sponge). Homogenize and incubate at 42 ± 1°C for 18–24 h. Note: For environmental samples, the collection device should first be dampened with a sterile diluent (e.g., buffered peptone water) containing, if necessary, a suitable neutralizing agent (e.g., Lecithin‑Polysorbate‑L-Histidine‑Sodium thiosulfate mixture or Dey Engley). Note: Incubation conditions may have repercussions on short detection procedures. The temperatures indicated must be scrupulously respected. In particular, it is advisable to ensure that the conditions for preheating the enrichment broth enable the indicated temperature to be reached. The sample preparation time (time between the end of the enrichment broth pre‑heating phase and the start of the food sample incubation phase), must not exceed 45 minutes. It is recommended to use a ventilated incubator for the incubation phase. Note: Extending the enrichment time to 24 hours allows for performance improvement of the alternative method only for large portions of raw meat products . (a) Following incubation, manually mix the contents of the blender bag. Optionally, a sterile technique can be used to remove 1 mL of enriched sample; place it in a pre-labeled microcentrifuge tube. Note: Do not discard the individual enriched samples until the analysis is complete and it has been confirmed that no further testing is required. Enriched samples can be stored at 2–8°C for up to 72 h before performing analysis. (b) Use the plate map created in the GENE-UP ® Routine software to determine the number of lysis tubes required from the GENE-UP ® Lysis Kit and place the correct number of lysis tubes E. Sample Lysis

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