AOAC RI ERP Final Action Recommendations eBook

FINAL (Version 4)

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

Orange juice (25 mL) – Weigh 25 g test portion into 225 mL pre-warmed (35°C) universal pre- 1 enrichment broth, C(j), and swirl thoroughly. Let stand at room temperature for 55-65 minutes. Do 2 not mix or adjust pH. Incubate, B(m), at 35°C for 22-26 hours. 3 Note: Re-growth is required for this sample type. 4 Orange juice (25 mL) – Weigh 25 g test portion into 225 mL pre-warmed (41°C) BAX® System MP 5 media, C(a), and swirl thoroughly. Incubate, B(m), at 39-42°C for 22-26 hours. 6 Note: Re-growth is required for this sample type. 7 Nonfat dry milk (25 g) – Pour 25 g sample slowly over the surface of 225 mL pre-warmed (35°C) 8 Brilliant Green Water, C(c). Let stand at room temperature for 55-65 minutes. Do not mix or adjust 9 pH. Incubate, B(m), at 35°C for 22-26 hours. 10 Note: Re-growth is required for this sample type. 11 Stainless steel, ceramic tile, plastic – Add 225 mL pre-warmed (35°C) LB, C(e), to environmental 12 sponge in sample bag and swirl thoroughly. Let stand at room temperature for 55-65 minutes. 13 Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, C(k), if necessary. Incubate, B(m), at 35°C for 22-26 14 hours. 15 Stainless steel, ceramic tile, plastic – Add 225 mL pre-warmed (35°C) BPW, C(d), to environmental 16 sponge in sample bag and swirl thoroughly. Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, C(k), if 17 necessary. Incubate, B(m), at 35°C for 18-24 hours. 18 Cocoa (25 g) - Weigh 25 g test portion into sterile container. Use a stomacher, B(n), to homogenize 19 sample for 2 minutes with 225 mL reconstituted nonfat dry milk, C(i). Let stand at room temperature 20 for 55-65 minutes, then swirl thoroughly to mix. Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, 21 C(k), if necessary. Add 0.45 mL 1% aqueous brilliant green dye solution, C(l), and mix well. Incubate, 22 B(m), at 35°C for 22-26 hours. Transfer 10 µL enrichment to 500 µL BHI broth, C(b) before 23 processing. 24 White pepper (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) TSB, C(f). Let stand at room 26 temperature for 55-65 minutes. Adjust pH to 6.8±0.2 using 1 N HCl or 1 N NaOH, C(k), if necessary. 27 Incubate, B(m), at 35°C for 22-26 hours. 28 Dry Pet Food (375 g) – Weigh 375 g test portion into sterile container. Use a stomacher, B(n), to 29 homogenize sample for 2 minutes with approximately one-third to one-half of 3375 mL pre-warmed 30 (35°C) LB, C(e). Add the remainder of the pre-warmed media. Adjust pH to 6.8±0.2 using 1 N HCl or 31 1 N NaOH, C(k), if necessary. Incubate, B(m), at 35°C for 22-26 hours. 32 Note: Re-growth is required for this sample type. 33 Dry Pet Food (375 g) – Weigh 375 g test portion into sterile container. Use a stomacher, B(n), to 34 homogenize sample for 2 minutes with approximately one-third to one-half of 3375 mL pre-warmed 35 (35°C) BPW, C(d). Add the remainder of the pre-warmed media. Adjust pH to 6.8±0.2 using 1 N HCl 36 or 1 N NaOH, C(k), if necessary. Incubate, B(m), at 35°C for 22-26 hours. 37 Note: Re-growth is required for this sample type. 38

DuPont Nutrition & Health

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