title: Studies to evaluate chemicals and conditions with low-pressure applications for reducing microbial counts on cattle hides.
abstract: Studies were conducted to identify effective antimicrobials and application parameters that could be used as decontamination interventions to reduce microbial loads on cattle hides before removal from carcasses. In study I, hide swatches inoculated with Escherichia coli O157:H7 were sprayed with 10% acetic acid (at 23 and 55 degrees C), 10% lactic acid (at 23 and 55 degrees C), 3% sodium hydroxide (at 23 degrees C) or 4 and 5% sodium metasilicate (at 23 degrees C). All antimicrobials were evaluated independently after being applied alone, being applied after a water rinse, or being followed by a water rinse. Antimicrobial treatments followed by a water rinse lowered E. coli O157:H7 populations by 0.6 to 2.4 log CFU/cm2 and resulted in hides with a surface pH of 6.3 to 9.2. Treatments in which a water rinse was followed by antimicrobial application lowered E. coli O157:H7 populations by 1.5 to 5.1 log CFU/cm2 but resulted in hides with a surface pH of 3.9 to 10.5. In study II, whole hides were treated with one of four antimicrobials (acetic acid, lactic acid, sodium hydroxide, or sodium metasilicate) followed by a water rinse. Hides were evaluated for aerobic bacterial counts, total coliform counts, and E. coli counts. Generally, all antimicrobials resulted in greater reductions (P < 0.05) of E. coli counts when compared with the control; however, only acetic and lactic acids resulted in greater reductions (P < 0.05) of aerobic bacterial counts and total coliform counts compared with the controls. These antimicrobials could be used to reduce microbial contamination on hides, potentially reducing microbiological contamination transferred to carcasses or to the plant environment.
authors.affiliation: Center for Meat Safety and Quality, Department of Animal Sciences, Colorado State University, Fort Collins, Colorado 80523-1171, USA.
authors.forename: Brandon A
authors.initials: BA
authors.lastname: Carlson
authors.forename: Ifigenia
authors.initials: I
authors.lastname: Geornaras
authors.forename: Yohan
authors.initials: Y
authors.lastname: Yoon
authors.forename: John A
authors.initials: JA
authors.lastname: Scanga
authors.forename: John N
authors.initials: JN
authors.lastname: Sofos
authors.forename: Gary C
authors.initials: GC
authors.lastname: Smith
authors.forename: Keith E
authors.initials: KE
authors.lastname: Belk
mesh_terms: D019342:Acetic Acid / Q000494:pharmacology; D000818:Animals; D002417:Cattle / Q000382:microbiology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004202:Disinfectants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D005525:Food-Processing Industry / Q000379:methods / Q000592:standards; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000494:pharmacology; D017640:Silicates / Q000494:pharmacology; D012867:Skin / Q000382:microbiology*; D012972:Sodium Hydroxide / Q000494:pharmacology; D013696:Temperature
chemical_list: D004202:Disinfectants; D017640:Silicates; C025349:sodium metasilicate; D019344:Lactic Acid; D012972:Sodium Hydroxide; D019342:Acetic Acid