Incidence of Escherichia coli O157:H7 in frozen beef patties produced over an 8-hour shiftt.

A ground beef patty processor detected Escherichia coli O157:H7 in five production lots during routine testing with polymerase chain reaction (PCR) technology. This finding stimulated research to determine the incidence and potential entry points of the pathogen during processing. One of these lots (53,960 kg) was divided into 71 pallets (760 kg each) of food service ground beef patties.

Assessment of Three Nucleic Acid Hybridization Systems for Detection of Campylobacter spp. in Poultry Products.

Three commercially available nucleic acid hybridization systems were evaluated in combination with the United States Department of Agriculture-Food Safety and Inspection Service (USDA/FSIS) cultural protocol for the detection of Campylobacter spp. from a variety of poultry products. Samples were enriched for 24 h in Hunt broth and then plated onto modified charcoal Campylobacter differential agar.

Comparison of Nucleic Acid Hybridization Assays and Biochemical Characterization Tests for the Confirmation of Listeria monocytogenes.

A comparison was made of various biochemical and nucleic acid hybridization assays used for the confirmation of Listeria monocytogenes . Identification and confirmation tests included traditional carbohydrate utilization tests, several types of hemolysis assays, an immunocompromised mouse-pathogenicity test, the API LISTERIA identification system, the Biolog GP MicroPlate™, a prototype Biolog Listeria MicroPlate, and two nucleic acid hybridization assays (a slot-blot assay and the commercially available AccuProbe L. monocytogenes culture confirmation test).

Isolation of Escherichia coli 0157:H7 Using 0157 Specific Antibody Coated Magnetic Beads.

Escherichia coli 0157 specific antibody, coated on magnetic beads, was used to concentrate and remove the E. coli 0157:H7 from mixed cultures and meat samples. The problem of nontarget organism carryover was addressed by adding Protamine to the culture-bead sample, washing the beads three times in saline, and changing the test tubes with each wash.

Use of 5-Bromo-4-Chloro-3-lndoxyl-β-D-Glucuronide in MacConkey Sorbitol Agar to Aid in the Isolation of Escherichia coli 0157:H7 from Ground Beef.

The addition of 5-bromo-4-chloro-3-indoxyl-β-D-glucuronide (BCIG) at the 0.1 g/L level, to MacConkey sorbitol agar (MSA) plates aided in the isolation of Escherichia coli 0157:H7 from raw ground beef samples by differentiating β-glucuronidase positive from β-glucuronidase negative colonies. E.