Tecra Ultima - Aoac 998.09 s1

TECRA ULTIMA - AOAC 998.09

SCOPE This method is applicable to:  Raw meats and carcass swabs.

PRINCIPLES The detection of Salmonella spp. is broken down into stages as follows:

. Pre-enrichment in non-selective liquid medium A 1:10 dilution of the sample must be pre-enriched in buffered peptone water at 36 ± 1C for 16-20 h. Buffered peptone water should be warmed to room temperature or to 36 C for large volumes. For carcass sponges, buffered peptone water is added to the moistened sponge to bring the total volume to 60-100 mL and the sample incubated at 36 ± 1C for 16-20 h. In the case of sponges BPW need not be warmed to room temperature before being used to re-hydrate the sponge, for all subsequent additions BPW should be warmed to room temperature.

. Enrichment in selective liquid medium Culture from the pre-enrichment broth (0.1 mL) is inoculated into selective liquid media, Rappaport-Vassiliadis R10 broth, and incubated at 42 ± 1C for 18-24 h.

. Addition of additive RV broth is mixed by hand. 25 L of sample ULTIMA additive1 is added to a tube followed by 1 mL of RV broth, after mixing the culture is then heated in boiling water or steam for 15 min. Remaining RV broth is retained under refrigeration for confirmation if necessary.

. Enzyme immunoassay Follow the manufacturer’s instructions using the cooled inactivated RV broth culture.

. Cultural confirmation Using the retained selective enrichment, proceed with Salmonella analysis as per AS 5013.10 (starting from ‘Plating out and Identification’). Confirmation carried out at an ‘off-site’ laboratory must be from retained BPW enrichment.

1 Contains hydroxymethyl aminoethane and polyoxyethylenesorbitan monolaurate in water Issue 2016 03 23 | Approved Methods Manual Export Standards Branch | Exports Division Page 1 of 2 Department of Agriculture and Water Resources Salmonella Detection-TECRA ULTIMA– AOAC 998.09

CHECKLIST

Pre- For meat product samples is PBW warmed to enrichment room temperature (to 36 ± 1C for large quantities)? Is the correct amount of enrichment broth used for the weight of sample analysed?

Is pre-enrichment done at 36 ± 1C for 18 h? Is a positive control run with each batch of samples analysed? Are reference cultures inoculated into primary enrichment broth at a level of 10 to 100 cells? Selective- Is the RV broth incubated at 42 ± 1C for 18-24 h? enrichment Post- Is ULTIMA additive added to RV broth prior to enrichment heating? Are selective enrichments stored correctly for possible cultural confirmation? Enzyme Are the manufacturer’s instructions available? immunoassay Cultural Is Salmonella isolated in-house from enrichment confirmation broths? (if applicable) If an external laboratory is used is it department approved? BPW should be supplied to off-site laboratories for confirmation following AS 5013.10 Are Salmonella confirmed using AS 5013.10 (with appropriate selective agar plates)?

Issue 2016 03 23 | Approved Methods Manual Export Standards Branch | Exports Division Page 2 of 2 Department of Agriculture and Water Resources