| dc.description.abstract | Shiga toxin-producing Escherichia coli are enteric pathogens that can cause severe illnesses in humans including Hemolytic Uremic Syndrome (HUS) and Hemorrhagic Colitis (HC). These pathogens may be present in the gastrointestinal tract and hide of cattle and during the harvesting process might be transmitted to the meat. It is of significant importance to prevent the contamination of check and head meat, as these are often used in the production of ground beef. If the head or cheek meat has been contaminated with pathogens during head processing, that contamination can further spread during grinding.
The purpose of this study is to examine the application of commonly used carcass antimicrobial interventions [lactic acid (LA), peroxyacetic acid (PAA), acidified peroxyacetic acid (aPAA), and 1,3-Dibromo-5,5-dimethylhydantoin (DBDMH)] for the reduction of STEC on fresh head and cheek meat during beef head processing. On the first phase of the study four replications were performed. Beef heads (n=20) were inoculates with STEC surrogates and assigned to one of 10 different treatments for 5 or 15 min: 1. Control (no treatment), 2. Water, 3. 1% LA, 4. 2% LA, 5. 200 ppm PAA, 6. 400 ppm PAA, 7. 200 ppm aPAA, 8. 400 ppm aPAA, 9. 200 ppm DBDMH and 400 ppm DBDMH. For the second phase of the study two additional replicates of 4 different treatments were performed: control, water, 2% LA, and 400 ppm PAA. After each treatment, the heads were allowed to drip for 5 min, and were then sampled to obtain head and cheek meat subsamples. The subsamples were subjected to serial dilutions using BPW and plated into 3M™ Petrifilm™ E. coli/Coliform count plates for enumeration.
Results from this study showed that dipping treatments including 2% LA, and 400 ppm PAA are capable of significantly (P < 0.05) reduce surface bacteria on fresh head and check meat by more than 1.2 log CFU/g. Neither water nor DBDMH dipping treatment produced a significant reduction on head or cheek meat surface bacteria. Further investigations are recommended in order to validate an adequate system to be employed within beef processing facilities to provide adequate decontamination of heads while preventing cross-contamination. | |
