2013 ISPAM Mid-Year Mtg Book

Pre-enrichment – time and temperature, other considerations Time and Temperature Requirements AOAC 24 ± 2 h at 35 ± 2°C – BAM (FDA) – 24 ± 2 h at 35 ± 2°C MLG (FSIS-USDA) – varies with food, 18-24 h, 20-24h or 22-26h (all ± 2°C)

HC – 18-24h at 35 ± 1°C ISO – 18 ± 2 h at 37 ± 1°C Other considerations – variable requirements for:

- Need for pH adjustment

- Pre-soaking of dry ingredients

- Thawing requirements for frozen product

- Formulation differences for “same named” broths.

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Selective Enrichment – media, time and temperature AOAC - in 967.27 -selenite cystine (SC) and tetrathionate (TT) (both1 mL in 10, 35°C, 24± 2h) – one exception for dry yeast substituting lauryl sulfate tryptose broth for selenite cystine) , ± an TT (1 mL in 10, 43 ± 0.2°C, 24± 2h for foods with a high microbial load OR 1 mL in 10, 35 ± 2°C, 24± 2h for foods with a low microbial load ) – some exceptions (e.g., guar gum) BAM (FDA) – RV medium (0.1 mL in 10, 42 ± 0.2°C, 24± 2h) and TT (1 mL in 10, 43 ± 0.2°C, 24± 2h for foods with a high microbial load OR 1 mL in 10, 35 ± 2°C, 24± 2h for foods with a low microbial load). Exceptions as well for guar gum. i 995 20 d 2000 06 R - n . an t V ili di (RV) di me um . m n , ± . (0 1 L i 10 42 0 2°C 24 2h) d . – appapor - ass a s

MLG (FSIS-USDA) – RV medium (mRV, RVS or RV R10 broth medium) and TT (both 0.5 mL in 10, 42 ±

0.5°C, 22-24 h in an incubator or 18-24 h in a waterbath)

HC – RVS (0.1 mL in 10) and TT (1 mL in 10), RVS and TT (42.5 ± 0.2°C for 24 ±2h) – an option to substitute RVS with SC

ISO – RVS (0.1 mL in 10, 41.5 ± 1.0°C for 24 ±3h) and MKTT (1 mL in 10, 37 ± 1.0°C for 24 ±3h)

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