title: Survival of Escherichia coli O157:H7 in meat product brines containing antimicrobials.
abstract: Brine solution injection of beef contaminated with Escherichia coli O157:H7 on its surface may lead to internalization of pathogen cells and/or cross-contamination of the brine, which when recirculated, may serve as a source of new product contamination. This study evaluated survival of E. coli O157:H7 in brines formulated without or with antimicrobials. The brines were formulated in sterile distilled water (simulating the composition of freshly prepared brines) or in a nonsterile 3% meat homogenate (simulating the composition of recirculating brines) at concentrations used to moisture-enhance meat to 110% of initial weight, as follows: sodium chloride (NaCl, 5.5%) + sodium tripolyphosphate (STP, 2.75%), NaCl + sodium pyrophosphate (2.75%), or NaCl + STP combined with potassium lactate (PL, 22%), sodium diacetate (SD, 1.65%), PL + SD, lactic acid (3.3%), acetic acid (3.3%), citric acid (3.3%), nisin (0.0165%) + ethylenediamine tetraacetic acid (EDTA, 200 mM), pediocin (11000 AU/mL) + EDTA, sodium metasilicate (2.2%), cetylpyridinium chloride (CPC, 5.5%), or hops beta acids (0.0055%). The brines were inoculated (3 to 4 log CFU/mL) with rifampicin-resistant E. coli O157:H7 (8-strain composite) and stored at 4 or 15 °C (24 to 48 h). Immediate (0 h) pathogen reductions (P < 0.05) of 1.8 to ≥ 2.4 log CFU/mL were observed in brines containing CPC or sodium metasilicate. Furthermore, brines formulated with lactic acid, acetic acid, citric acid, nisin + EDTA, pediocin + EDTA, CPC, sodium metasilicate, or hops beta acids had reductions (P < 0.05) in pathogen levels during storage; however, the extent of pathogen reduction (0.4 to > 2.4 log CFU/mL) depended on the antimicrobial, brine type, and storage temperature and time. These data should be useful in development or improvement of brine formulations for control of E. coli O157:H7 in moisture-enhanced meat products.
  
  
  CONCLUSIONS
  Results of this study should be useful to the meat industry for developing or modifying brine formulations to reduce the risk of E. coli O157:H7 in moisture-enhanced meat products.
authors.affiliation: Center for Meat Safety & Quality, Dept of Animal Sciences, Colorado State Univ, Fort Collins, CO 80523-1171, USA.
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Adler
authors.forename: Ifigenia
authors.initials: I
authors.lastname: Geornaras
authors.forename: Oleksandr A
authors.initials: OA
authors.lastname: Byelashov
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; D000890:Anti-Infective Agents / Q000008:administration & dosage*; D002417:Cattle; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000502:physiology*; D005511:Food Handling / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000382:microbiology*; D012492:Salts
chemical_list: D000890:Anti-Infective Agents; D012492:Salts; C017082:brine