AOAC RI ERP Final Action Recommendations eBook

Collaborative Study Approved Protocol Expert Review Panel Use Only

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 ± 3 (h) Orange juice .— (1) Weigh 25 g test portion into 225 mL universal preenrichment broth, swirl 4 thoroughly and let stand for 60 ± 5 min at room temperature, then incubate, 24 ± 2 h at 35 ± 5 2 ° C. (2) Weigh 25 g test portion into 225 mL BAX® MP broth, mix, then incubate for 24 ± 2 h at 6 39-42 ° C. 7 (i) Cream cheese, lettuce, frozen peas. — (1) Weigh 25 g test portion into sterile container. Blend 8 sample for 2 min. with 225 mL lactose broth, let stand for 60 ± 5 min at room temperature. If 9 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. 10 (2) Weigh 25 g test portion into sterile container. Homogenize sample for 2 min. with 225 mL 11 MP media then incubate, 24 ± 2 h at 35 ± 2 ° C. 12 (j) Shrimp. —Weigh 25 g test portion into sterile container. Blend sample for 2 min. with 225 mL 13 lactose broth, let stand for 60 ± 5 min at room temperature. If necessary, adjust pH to 6.8 ± 0.2 14 using 1 N HCl or 1 N NaOH, then incubate, 24 ± 2 h at 35 ± 2 ° C. 15 (k) Environmental surfaces (stainless, tile, or plastic). — (1) Collect samples by sponge hydrated with 16 10mL DE broth. After returning the sponge to the sample bag, add 225 mL of LB. Swirl 17 thoroughly to mix and allow to stand 60 ± 5 min at room temperature. Again mix well by swirling 18 and determine pH with test paper. Using 1 N HCl or NaOH, adjust pH if necessary to 6.8 ± 0.2 19 then incubate 24 ± 2 h at 35 ± 2 ° C. (2) Collect samples by sponge hydrated with 10mL DE broth. 20 After returning the sponge to the sample bag, add 225 mL of BPW. Swirl or stomach to mix. 21 Using 1 N HCl or NaOH, adjust pH if necessary to 6.0-7.0 then incubate 21 ± 3 h at 35 ± 2 ° C. 22 (l) Shell eggs. — Add 2000 ± 100 mL of pre-warmed (42°C) MP enrichment media to 20 eggs (~1000 23 ml) and incubated for 48 hours at 42°C. 24 (m) White pepper. —(1) Aseptically weigh 25 g sample into sterile container. Add 225 ml trypticase 25 soy broth (TSB) and mix well. Let stand 60 ± 5 min at room temperature. Mix well by swirling 26 and determine pH with test paper. Adjust pH, if necessary, to 6.8 ± 0.2, then incubate 24 ± 2 h at 27 35° ± 2 ° C. (2) Weigh 25 g test portion into sterile container. Homogenize sample for 1-2 min 28 with 225 mL BPW, and incubate, 22 ± 2 h at 35 ± 2 ° C. 29 (n) Dried Eggs. —(1) Add about 15 ml sterile lactose broth and stir with sterile glass rod, spoon, or 30 tongue depressor to smooth suspension. Add 3 additional portions of lactose broth, 10, 10, and 31 190 ml, for total of 225 ml. Stir thoroughly until sample is suspended without lumps. Cap jar 32 securely and let stand 60 ± 5 min at room temperature. Mix well by swirling and determine pH. 33 Adjust pH, if necessary, to 6.8 ± 0.2 with sterile 1 N NaOH or 1 N HCl, then incubate, 24 ± 2 h at 34 35 ± 2 ° C. (2) 2) Weigh 25 g test portion into sterile container. Homogenize sample with 225 mL 35 BPW then incubate, 24 ± 2 h at 35 ± 2 ° C. 36 (o) Non-fat dry milk. —(1) Aseptically weigh 25 g sample into sterile container. Using sterile glass or 37 paper funnel (made with tape to withstand autoclaving), pour 25 g analytical unit gently and 38 slowly over surface of 225 ml brilliant green water contained in sterile 500 ml Erlenmeyer flask 39 or other appropriate container. Let container stand undisturbed for 60 ± 5 min. without mixing 40 or pH adjustment, for 24 ± 2 h at 35°C. (2) Weigh 25 g test portion into sterile container. 41 Homogenize sample with 225 mL BPW then incubate, 24 ± 2 h at 35 ± 2 ° C. 1 2 2 ° C.

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E. Assay

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