Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/17/1999
Publication Date: N/A
Interpretive Summary: Cetylpyridinium chloride (CPC), the active ingredient in Cepacol mouthwashes and Cepastat throat lozenges, is a water soluble, odorless and colorless compound. CPC also is known to kill or inhibit bacteria responsible for plaque formation and is widely used in other oral hygiene products. Recently, researchers have demonstrated that CPC kills foodborne bacteria on poultry surfaces. The following study was conducted to determine if CPC inhibits foodborne pathogens on beef surfaces inoculated with cow feces and subjected to different spray washing treatments. Spray washing (125 psi, 15 sec, 121 deg F) with CPC was performed with a carcass washer especially designed for research purposes. In two experiments conducted, pathogenic bacteria associated with lean or fat beef surfaces were inhibited immediately after spraying with CPC. In some instances, CPC prevented growth of pathogens on beef surfaces after long-term refrigerated storage. In another experiment, lean or fat beef tissue was washed with CPC, left undisturbed for 5, 10, 15, or 30 minutes and then washed with water. In addition to reducing the amount of residual CPC remaining on the tissue, pathogens also were inhibited. Processing of CPC-treated fat or lean beef into ground beef appeared to significantly dilute the residual CPC; however, average residue levels found in ground beef treated with CPC are in excess of what could be considered safe. This study is the first to demonstrate the effect of CPC on pathogens associated with beef.
Technical Abstract: Cetylpyridinium chloride (CPC) is a water soluble, neutral pH, colorless compound and is widely used in oral hygiene products to inhibit plaque. CPC reduces Salmonella Typhimurium on poultry surfaces and also prevents cross contamination. In this study, experiments were conducted to determine the effectiveness of CPC against foodborne pathogens on beef surfaces. Antibiotic resistant pathogens were inoculated on to lean or adipose beef surfaces, left untreated, or spray washed (125 psi, 15 s, 35 deg C) with water or 1% (wt/vol) CPC. For lean beef, CPC immediately reduced populations of E. coli O157:H7 (EC) and S. Typhimurium (ST) to virtually undetectable levels. Aerobic plate counts (APC) also were effectively reduced to less than 1 log CFU/cm**2. After 35 days of refrigerated (4 deg C), vacuum-packaged storage, CPC-treated surfaces exhibited APC of 1.7 log CFU/cm**2; selective enrichment did not recover EC or ST. Adipose surfaces inoculated with EC or ST were reduced >2.5 log CFU/cm**2 at day 0; by day 35, ST and EC were reduced 0.10 to 1.34 log CFU/cm**2. On lean beef that had been inoculated with EC or ST, washed with 1% CPC, left untreated (C0) or undisturbed for 5 (C5), 10 (C10), 15 (C15), or 30 (C30) min, and subjected to a secondary water wash (15 s, 125 psi) pathogens were not reduced to a large extent when subjected to C30 treatments; however, by day 50, no pathogens were detected from any samples. This study is the first to demonstrate the effect of CPC on aerobic and pathogenic bacteria associated with beef surfaces, immediately after treatment and also after long term, refrigerated, vacuum packaged storage.