Food PT scheme sample instruction sheet
Shellfish

The final date for return of results is indicated on the accompanying request/report form

Contact details:
The Organisers - FEPTU
UK Health Security Agency
61 Colindale Avenue,
London, NW9 5EQ, UK.
Tel: +44 (0) 20 8327 7119
e-mail: foodeqa@ukhsa.gov.uk
Results should be returned on-line using the web-based reporting system. Go to: www.phe-eqa.org.uk. You will need your log-in details for this process. Please contact us if you experience problems with the on-line system.

Shellfish Scheme – Instruction Sheet

Each distribution consists of two LENTICULE® discs in screw-cap plastic vials (with desiccant).The LENTICULE discs require reconstitution by a process of re-hydration and dispersion prior to examination.

Refer also to the Safety Data Sheet: Safety data sheet - LENTICULE

For a video on sample processing: Sample processing - Shellfish

Storage:

  • Store the samples at –20 ± 5ºC on receipt.
  • Allow the LENTICULE discs to reach ambient temperature (5 - 10 minutes) before reconstituting in diluent.

Reconstitution:

  • Open the sample container and transfer the LENTICULE disc in to 100mL nutrient broth.
  • Leave at ambient temperature for a minimum of 10 minutes to rehydrate. Ensure that the LENTICULE disc has completely dissolved before proceeding.
  • Disperse the inoculum by inverting approximately 30 times.

Examination:

  • Each reconstituted sample is equivalent to a 100 g food sample.
  • Undertake the examinations listed on the request/report form between 30 - 45 minutes after reconstitution.
  • Prepare a 1 in 10 dilution of each sample by transferring 10 mL reconstituted sample (stomached homogenate) to 90mL diluent (master 10-¹ dilution). Perform most probable number (MPN) tests for E. coli on each sample using your routine method. The test should be performed in duplicate for both samples.
  • Examine samples for E. coli (MPN) and Salmonella spp. according to your routine methods

Reporting:

The online form is based on three by five tube/plate segment combinations. Please indicate the combination used to determine the MPN from the MPN table. This will help with the statistical analyses of the results. Report the MPN per 100g for E. coli.

Return of Results:

  • Return your results on-line using the web-based reporting system.
  • Return results to the organisers before the deadline shown on the request/report form.
  • Results returned after that date will not be assessed.