AOAC RI ERP Final Action Recommendations eBook

Collaborative Study Approved Protocol Expert Review Panel Use Only

(j) Rappaport-Vassiliadis Soya Peptone (RVS), Selenite Cystine (SC), Tetrathionate-Hajna (TT- Hajna) and Tetrathionate (TT) broths and Xylose Lysine Desoxycholate (XLD), Hektoen Enteric (HE), Brilliant Green Sulfa (BGS) and Bismuth Sulfite (BS) agars.– and other

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appropriate confirmatory media for culture confirmation.

D. Sample Enrichment 6 7 Note: Unless otherwise specified all samples should be enriched in pre-warmed media. Unless 8 otherwise specified all samples were validated with and without a 1:50 regrowth (10 µL or 9 enriched sample in 500 µL of BHI broth) for 3 hrs at 37 ± 2 ° C before performing lysis and PCR. 10 The following matrices were validated only with a regrowth: dry pet food, peanut butter, 11 orange juice, and non-fat dry milk. (a) Frankfurters. —Weigh 325 g test portion into sterile container. Add approximately one third to one-half of 2925 ± 58.5 mL of sterile buffered peptone water (BPW) to each portion. Homogenize for approximately 2 minutes and then add the remainder of the 2925 ml of BPW. (b) Ground beef .—(1) Weigh 375 g test portion into sterile container. Add 1500 ± 75 mL of sterile mTSB plus 2 mg/L novobiocin to each portion. Homogenize for approximately 2 minutes. Incubate for 24 ± 2 h at 35 ± 2 ° C. (2) Weigh 25 g test portion into sterile container. Homogenize sample for approximately 2 min. with 225 mL buffered peptone water, and incubate, 20-24 h at (c) Ground beef with soy .—(1) Weigh 325 g test portion into sterile container. Add 975 ± 32.5 mL of sterile mTSB with casaminoacids and 8 mg/L novobiocin to each portion. Homogenize for approximately 2 minutes. Incubate for 22 ± 2 h at 35 ± 2 ° C. (2) Weigh 25 g test portion into sterile container. Homogenize sample for 2 min. with 225 mL BPW, and incubate, 22 ± 2 h at 35 (d) Dry Pet Food. —Weigh 375 g test portion into sterile container. Add approximately one third to one-half of 3375 ± 67.5 mL of sterile LB or BPW to each portion. Homogenize for approximately 2 minutes and then add the remainder of the 2925 ml of the media. Incubate for 24 ± 2 h at 35 ± (e) Ice Cream .—(1) Weigh 25 g test portion into sterile container. Homogenize sample with 225 mL lactose broth, let stand for 60 ± 5 min at room temperature. If necessary, adjust pH to 6.8 ± 0.2 using 1 N HCl or 1 N NaOH, then incubate, 24 ± 2 h at 35 ± 2 ° C. (2) Weigh 25 g test portion into sterile container. Homogenize sample with 225 mL BPW then incubate, 24 ± 2 h at 35 ± 2 ° C. (3) Weigh 25 g test portion into sterile container. Homogenize sample with 225 mL Brilliant Green Incubate for 21 ± 3 h at 35 ± 2 ° C. 35 ± 2 ° C. ± 2 ° C. 2 ° C. Regrowth must be performed for this matrix. (f) Poultry rinse .—Combine 30 ml BPW rinsate with 30 mL of either double-strength BPW (if chickens were rinsed in Butterfield’s Phosphate Buffer) or in single-strength BPW if chickens (g) Peanut butter .—(1) Weigh 25 g test portion into sterile container. Homogenize sample with 225 mL lactose broth, let stand for 60 ± 5 min at room temperature. If necessary, adjust pH to 6.8 ± were rinsed in BPW. Incubate 24 ± 2 h at 35 ± 2 ° C. 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Water, then incubate, 24 ± 2 h at 35 ± 2 ° C.

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