title: Evaluation of brining ingredients and antimicrobials for effects on thermal destruction of Escherichia coli O157:H7 in a meat model system.
abstract: Escherichia coli O157:H7 may become internalized during brine injection of meat. This study evaluated the effect of brining ingredients on E. coli O157:H7 in a meat model system after simulated brining, storage, and cooking. Fresh knuckles (5.3 +/- 2.4% fat) or beef shoulder (15.3 +/- 2.2% fat) were ground individually, mixed with an 8-strain composite of rifampicin-resistant E. coli O157:H7 (7 log CFU/g) and brining solutions. Treatments included no brining, distilled water, sodium chloride (NaCl, 0.5%), sodium tripolyphosphate (STP, 0.25%), sodium pyrophosphate (SPP, 0.25%), NaCl + STP, NaCl + SPP, NaCl + STP + potassium lactate (PL, 2%), NaCl + STP + sodium diacetate (SD, 0.15%), NaCl + STP + PL + SD, NaCl + STP + lactic acid (0.3%), NaCl + STP + acetic acid (0.3%), NaCl + STP + citric acid (0.3%), NaCl + STP + EDTA (20 mM) + nisin (0.0015%) or pediocin (1000 AU/g), NaCl + STP + sodium metasilicate (0.2%), NaCl + STP + cetylpyridinium chloride (CPC; 0.5%), and NaCl + STP + hops beta acids (0.00055%). Samples (30 g) were analyzed for pH, and total microbial and rifampicin-resistant E. coli O157:H7 (inoculum) populations immediately after mixing, storage (24 h at 4 degrees C), and cooking to 65 degrees C. Fat and moisture contents and water activity were measured after storage and cooking only; cooking losses also were determined. The effect of beef type on microbial counts, pH, and water activity was negligible. No reductions in microbial counts were obtained by the brining solutions immediately or after storage, except for samples treated with CPC, which reduced (P < 0.05) pathogen counts after storage by approximately 1 log cycle. Cooking reduced pathogen counts by 1.5 to 2.5 logs, while CPC-treated samples had the lowest (P < 0.05) counts compared to any other treatment. These data may be useful in developing/improving brining recipes for control of E. coli O157:H7 in moisture-enhanced beef products.
authors.affiliation: Center for Meat Safety & Quality and Food Safety Cluster, Dept. of Animal Sciences, Colorado State Univ., 1171 Campus Delivery, Fort Collins, CO 80523, USA.
authors.forename: Oleksandr A
authors.initials: OA
authors.lastname: Byelashov
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Adler
authors.forename: Ifigenia
authors.initials: I
authors.lastname: Geornaras
authors.forename: Kyung Yuk
authors.initials: KY
authors.lastname: Ko
authors.forename: Keith E
authors.initials: KE
authors.lastname: Belk
authors.forename: Gary C
authors.initials: GC
authors.lastname: Smith
authors.forename: John N
authors.initials: JN
authors.lastname: Sofos
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002417:Cattle; D002594:Cetylpyridinium / Q000494:pharmacology; D015169:Colony Count, Microbial; D004041:Dietary Fats / Q000032:analysis; D024881:Drug Resistance, Bacterial; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development* / Q000302:isolation & purification; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D005520:Food Preservatives / Q000737:chemistry / Q000494:pharmacology*; D005517:Foodborne Diseases / Q000517:prevention & control; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000032:analysis / Q000382:microbiology*; D050296:Microbial Viability / Q000187:drug effects; D008954:Models, Biological; D012293:Rifampin / Q000494:pharmacology; D012492:Salts / Q000737:chemistry / Q000494:pharmacology*; D014867:Water / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D004041:Dietary Fats; D005520:Food Preservatives; D012492:Salts; C017082:brine; D014867:Water; D002594:Cetylpyridinium; D012293:Rifampin