title: Efficacy of knife disinfection techniques in meat processing.
abstract: EU Regulation 853/2004 requires that knives used in meat processing be disinfected by submerging them in hot water (+82°C). Alternative procedures are permitted if the efficacy is proved to be equivalent. In the present study, various time-temperature combinations together with pure water, water with lactic acid (2 %), and the use of ultrasound with and without lactic acid (2%) were investigated. Steel plates were covered with fat and protein and then inoculated with a standardized bacterial contamination assembled according to the composition of bacterial contamination found in a previous field trial conducted with regard to the slaughter of pigs. Several combinations with diverse temperatures and time intervals were tested until no microbial load was detectable by using a wet-dry-swab technique that had previously been tested to ensure maximum bacterial recovery. The following were effective in bringing the tested bacterial flora below the detection limit: • 70 °C water bath for 10 s • 60 °C water bath + ultrasound for 5 s • 40 °C water bath + lactic acid (2%) for 10 s • 40 °C water bath + ultrasound + lactic acid (2%) for 5 s In particular, the use of lactic acid permitted a relevant reduction of the temperature, while providing effective sterilization. The use of such non-hazardous food-safe additives is particularly suitable for successful disinfection at lower temperatures.
authors.affiliation: Panel Veterinary Public Health, Institute of Meat Hygiene and Technology, Faculty of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany. fleischhygiene@vetmed.fu-berlin.de
authors.forename: J
authors.initials: J
authors.lastname: Leps
authors.forename: K
authors.initials: K
authors.lastname: Einschütz
authors.forename: N
authors.initials: N
authors.lastname: Langkabel
authors.forename: R
authors.initials: R
authors.lastname: Fries
mesh_terms: D000818:Animals; D015169:Colony Count, Microbial; D004202:Disinfectants / Q000494:pharmacology; D004203:Disinfection / Q000379:methods*; D021902:Enterobacter aerogenes / Q000187:drug effects / Q000254:growth & development; D005506:Food Contamination / Q000517:prevention & control*; D005511:Food Handling / Q000295:instrumentation* / Q000379:methods*; D005516:Food Microbiology; D019344:Lactic Acid / Q000494:pharmacology; D008089:Listeria monocytogenes / Q000187:drug effects / Q000254:growth & development; D008460:Meat / Q000382:microbiology*; D015203:Reproducibility of Results; D013016:Sound; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development; D013552:Swine; D013696:Temperature
chemical_list: D004202:Disinfectants; D019344:Lactic Acid