Microbiology Methods for ERP Review 3-2020

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GENE ‐ UP ® SLM 2 Collaborative Study

July 2019

ASAP and CHROMID Salmonella. The recovered isolates will be identified by API20E (Official Method 978.24) or VITEK GN (Official Method 2011.17). The somatic (O) and flagellar (H) tests will also be performed. e) Most Probable Number (MPN) Analysis. The level of Salmonella will be determined by MPN on the day of analysis on the low and high inoculation levels. Prepare 5 test portions of 50 g and 5 test portions of 10 g for the low level and 5 test portions of 10 g and 5 test portions of 5 g for the high level. Use the replicate test portions analyzed by the reference method in the matrix study as the third level for the MPN. See Table 2. Test portions will be evaluated following the reference method through to confirmations. The number of positives from the large, medium, and small test portions will be used to calculate the MPN (and 95% confidence intervals) for each inoculated level using the MPN calculator (http://www.lcfltd.com/customer/LCFMPNCalculator.exe)

Table 2. MPN Test Portions for Low and High Inoculation Levels Matrix Inoculation Level Large Test Portions Medium Test Portions

Small Test Portions

Reference Method MLG 4.10

Low High

5 x 50 g

25 g*

5 x 10 g 5 x 5 g

Raw Ground Beef (80% lean)

25 g*

5 x 10 g

*Test portions from matrix study analyzed by the reference method

5) GENE ‐ UP Salmonella 2 (SLM 2) Method

a) Applicability

Applicable to detection of Salmonella in 25 g test portions of fresh raw ground chicken, fresh raw chicken breast, fresh raw ground beef (20% fat), fresh raw fish, creamy peanut butter, vanilla ice cream and dry pet food; for 30 mL test portions of chicken carcass rinse; for 100 g test portions of pasteurized liquid eggs and powdered egg,; for 375 g test portions of fresh raw ground beef (20% fat), raw beef trim, raw ground pork, raw ground bison, whey protein powder, dry pet food, creamy peanut butter, garlic powder, bulk bagged Romaine lettuce and dark chocolate; for stainless steel environmental sponges.

b) Test Kit Information a) GENE ‐ UP® Salmonella 2 (SLM 2). ― bioMérieux, Inc., REF 423105 (192 tests).

c) Test Kit Reagents  ‐ GENE ‐ UP® Salmonella 2 (192 tests). a) PCR Reagent Strips. ― Two pouches with 12 strips of 8 tubes (2 x 96 tubes). b) Op Ɵ cal Caps. ― Two pouches with 12 strips of 8 tubes (2 x 96 caps). c) Control Bu ff er. ― One pouch with control bu ff er vial.

d) Additional Supplies and Reagents a) GENE ‐ UP® Lysis Kit. ― bioMérieux, Inc., REF 414057. b) GENE ‐ UP® Thermocycler. ― bioMérieux, Inc., REF 414056. c) Laboratory paddle blender for sample homogenization.

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