AOAC RI ERP Final Action Recommendations eBook

FINAL (Version 4)

DuPont™ BAX ® System Real-Time PCR Assay for Salmonella : Collaborative Study

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Note: Re-growth is required for peanut butter.

Ground turkey, chicken wings (25 g) - Weigh 25 g test portion into sterile container. Use a 2 stomacher, B(n), to homogenize sample for 2 minutes with 225 mL pre-warmed (35°C) BPW, C(d). 3 Incubate, B(m), at 35°C for 16-24 hours. 4 Poultry rinse (30 mL) – Combine 30 mL BPW rinsate with 30 mL pre-warmed (35°C) BPW, C(d), into 5 sterile container. Incubate, B(m), at 35°C for 16-26 hours. 6 Dried Eggs (25 g) – Weigh 25 g test portion into sterile container. Add approximately 15 mL pre- 7 warmed (35°C) LB, C(e), to sample and stir to smooth. Add 3 additional aliquots of LB of 10 mL, 10 8 mL, and 190 mL (total media volume 225 mL), stirring after each addition. Let stand at room 9 temperature for 55-65 minutes. Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, C(k), if necessary. 10 Incubate, B(m), at 35°C for 22-26 hours. 11 Dried eggs, ice cream, peanut butter (25 g) - Weigh 25 g test portion into sterile container. Use a 12 stomacher, B(n), to homogenize sample for 2 minutes with 225 mL pre-warmed (35°C) BPW, C(d). 13 Incubate, B(m), at 35°C for 22-26 hours. 14 Note: Re-growth is required for peanut butter. 15 Shell Eggs (~1,000 mL) – Combine 20 eggs into sterile container with 2,000 mL pre-warmed (42°C) 16 BAX® System MP media, C(a). Incubate, B(m), at 42°C for 48 hours. 17 Frozen peas, cream cheese, ice cream, infant formula (25 g) - Weigh 25 g test portion into sterile 18 container. Use a stomacher, B(n), to homogenize sample for 2 minutes with 225 mL pre-warmed 19 (35°C) LB, C(e). Let stand at room temperature for 55-65 minutes. Adjust pH to 6.8±0.2 using 1 N HCl 20 or 1 N NaOH, C(k), if necessary. Incubate, B(m), at 35°C for 22-26 hours. 21 Frozen peas (25 g) – Weigh 25 g test portion into sterile container. Use a stomacher, B(n), to 22 homogenize sample for 2 minutes with 225 mL pre-warmed (35°C) BAX® System MP media, C(a). 23 Incubate, B(m), at 35°C for 22-26 hours. 24 Cream cheese (25 g) – Weigh 25 g test portion into sterile container. Use a stomacher, B(n), to 25 homogenize sample for 2 minutes with 225 mL pre-warmed (35°C) BAX® System MP media, C(a). 26 Incubate, B(m), at 35°C for 12-26 hours. 27 Fresh bagged lettuce (25 g) - Weigh 25 g test portion into sterile container. Add 225 mL pre-warmed 28 (35°C) LB, C(e), and swirl 25 times clockwise and 25 times counterclockwise. Let stand at room 29 temperature for 55-65 minutes. Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, C(k), if necessary. 30 Incubate, B(m), at 35°C for 22-26 hours. 31 Fresh bagged lettuce (25 g) – Weigh 25 g test portion into sterile container. Add 225 mL pre-warmed 32 pre-warmed (35°C) BAX® System MP media, C(a), and swirl 25 times clockwise and 25 times 33 counterclockwise. Incubate, B(m), at 35°C for 12-26 hours. 34 Ice cream (25 g) – Weigh 25 g test portion into sterile container. Use a stomacher, B(n), to 35 homogenize sample for 2 minutes with 225 mL pre-warmed (35°C) Brilliant Green Water, C(c). 36 Incubate, B(m), at 35°C for 22-26 hours. 37

DuPont Nutrition & Health

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