Evaluation of hot-water and sanitizer dip treatments of knives contaminated with bacteria and meat residue.

Hot water (HW; 82.2 degrees C, 180 degreesF) is used for sanitation of meat cutting implements in most slaughter facilities, but validation of actual practices against meat-borne bacterial pathogens and spoilage flora is lacking. Observed implement immersions in HW in two large pork processing plants were found to typically be < or = 1 s.

Growth potential of Clostridium perfringens during cooling of cooked meats.

Many meat-based food products are cooked to temperatures sufficient to inactivate vegetative cells of Clostridium perfringens, but spores of this bacterium can survive, germinate, and grow in these products if sufficient time, temperature, and other variables exist. Because ingestion of large numbers of vegetative cells can lead to concomitant sporulation, enterotoxin release in the gastrointestinal tract, and diarrhea-like illness, a necessary food safety objective is to ensure that not more than acceptable levels of C. perfringens are in finished products.

Incidence of Clostridium perfringens in commercially produced cured raw meat product mixtures and behavior in cooked products during chilling and refrigerated storage.

A total of 445 whole-muscle and ground or emulsified raw pork, beef, and chicken product mixtures acquired from industry sources were monitored over a 10-month period for vegetative and spore forms of Clostridium perfringens. Black colonies that formed on Shahidi-Ferguson perfringens (SFP) agar after 24 h at 37 degrees C were considered presumptive positive. Samples that were positive after a 15-min heat shock at 75 degrees C were considered presumptive positive for spores.

New and Established Carcass Decontamination Procedures Commonly Used in the Beef-Processing Industry .

The fate of Escherichia coli O157:H7 and salmonellae as well as other potentially pathogenic bacteria resulting from fecal and other sources of contamination on red meat carcasses is a major concern. The development and validation of various decontamination procedures for red meat carcasses is not a new research area. However, recent morbidity and mortality attributable to the presence of E.

Effects of Acetic Acid, Lactic Acid and Trisodium Phosphate on the Microflora of Refrigerated Beef Carcass Surface Tissue Inoculated with Escherichia coli O157:H7, Listeria innocua , and Clostridium sporogenes .

The microbial profiles of inoculated beef carcass tissue (BCT) were monitored during prolonged refrigerated vacuum-packaged storage following antimicrobial treatment. An industrial spray wash cabinet was used to deliver water (W), 1.5 and 3.

Parameters Affecting the Efficacy of Spray Washes against Escherichia coli O157:H7 and Fecal Contamination on Beef .

A series of progressive experiments was conducted with a model carcass washer using tap water and 2% acetic acid sprays to determine if tissue type, inoculation menstruum, bacterial level, or spray temperature affect removal of bacteria from beef carcass tissue during spray washing. For the first experiment, prerigor (15 min postexsanguination), postrigor (24 h postexsanguination), or postrigor frozen (-20°C, 7 days), thawed, lean beef carcass tissue (BCT) was inoculated with bovine feces and subjected to spray washing (15 s, 56°C) with water or acetic acid. Spray washing with either compound resulted in bacterial populations that were similar for prerigor and postrigor BCT; however, remaining bacterial populations from spray-treated postrigor, frozen BCT were significantly ( ≤ 0.

Effects of Steam-Vacuuming and Hot Water Spray Wash on the Microflora of Refrigerated Beef Carcass Surface Tissue Inoculated with Escherichia coli O157:H7, Listeria innocua , and Clostridium sporogenes .

The fates of several bacterial populations on beef carcass surfaces were examined immediately following hot water washes (W) delivered through a beef carcass wash cabinet or application of steam-vacuum (SV). Additionally, the long-range effectiveness of W and SV on several bacterial populations was also determined during storage up to 21 days at 5°C under vacuum-packaged conditions. Fresh, unaltered bovine feces spiked with antibiotic-resistant strains of Escherichia coli O157:H7, Listeria innocua , and Clostridium sporogenes were used to inoculate beef carcass tissue prior to W or SV treatment.

Application of Carnatrol™ and Timsen™ to Decontaminate Beef .

The spray application of two commercial decontaminating agents for reducing bacterial populations associated with fecal contamination on beef was examined in two separate experiments. Individual pieces of prerigor lean beef tissue were inoculated with fresh bovine feces and subjected to a 15-s spray wash (75 lb/in, 20°C) with water or various concentrations of Carnatrol™, composed of copper sulfate pentahydrate, or Timsen™, 40% -alkyldimethylbenzylammonium chloride in 60% stabilized urea, and stored under refrigerated (5°C) conditions. When Carnatrol™ was applied to beef tissue at 20, 40, and 80 ppm, bacterial populations were not statistically different ( ≥ 0.

Microbial Decontamination of Beef and Sheep Carcasses by Steam, Hot Water Spray Washes, and a Steam-Vacuum Sanitizer.

Three separate studies were conducted to determine the effectiveness of various temperature water spray washes (W), wash and steam combinations (WS), and vacuum and wash combinations (VW) for reducing fecal bacteria on sheep and beef carcasses. W of 15.6, 54.

Chlorine Dioxide Spray Washes for Reducing Fecal Contamination on Beef .

The ability of chlorine dioxide (ClO) to reduce bacterial populations (i.e., aerobic plate count, APC) on fecally contaminated beef carcass tissue (BCT) was examined in two separate experiments.

Use of a Rapid Microbial ATP Bioluminescence Assay to Detect Contamination on Beef and Pork Carcasses .

A new microbial ATP bioluminescence assay was shown to be an accurate and rapid method to determine the levels of generic bacterial contamination on beef ( = 400 and pork ( = 320) carcasses sampled in commercial processing plants. Based on in vitro fecal dilution studies, the rapid microbial ATP (R-mATP) assay is as accurate as the standard plate count method for estimating bacteria in bovine or porcine fecal samples. The correlations () between the R-mATP assay and the standard aerobic plate count for beef and pork carcasses sampled in commercial processing were 0.

Low Temperature Growth and Thermal Inactivation of Listeria monocytogenes in Precooked Crawfish Tail Meat .

Growth of Listeria monocytogenes in precooked crawfish tail meat at 0, 6, and 12°C was determined. Thermal death times were also determined. Growth curves for L.