Incidence of Escherichia coli O157:H7 in Frozen Beef Patties Produced over an 8-Hour Shift
Abstract: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. Ten cartons (19 kg each) were removed from each pallet, for a total of 710 cartons. Four patties were taken from each carton and subdivided to provide comparable samples for E. coli O157:H7 analyses by three different laboratories. Two laboratories employed different immunoassay tests, and one used PCR to screen samples. One sample set was analyzed for aerobic plate, coliform, and E. coli Biotype I counts to determine if any relationship existed between these microbial groups and the incidence of E. coli O157:H7. For 73 samples, presumptive positive results for E. coli O157:H7 were obtained by one or more methods. For 48 of these 73 samples, positive results for the pathogen were culture confirmed. The largest number (29) of culture-confirmed positive E. coli O157:H7 results were detected by PCR. Most positive results were obtained during a short segment of processing. All culture-confirmed E. coli O157:H7 strains were further characterized by two genetic subtyping techniques, resulting in two to four different patterns, depending on the subtyping procedure employed. For any sample tested, the aerobic plate count was <3.0 log CFU/g, and coliform and E. coli Biotype I counts were ≤1.00 log CFU/g. The results of this study suggest that most positive samples were associated with a contaminated batch of raw material introduced just before the 1725- to 1844-h processing segment. These results also indicate that more aggressive sampling plans and genetic screening technologies such as PCR may be used to better detect low levels of E. coli O157:H7 in ground beef products.
Document Type: Research Article
Affiliations: 1: Silliker Laboratories, 1304 Halsted Street, Chicago Heights, Illinois 60411 and ConAgra Refrigerated Prepared Foods, 3131 Woodcreek Drive, Downers Grove, Illinois 60515, USA 2: Texas American Food Service, 1301 Northpark Drive, Ft. Worth, Texas 76102, USA 3: Office of Public Health and Science, U.S. Department of Agriculture, Food Safety and Inspection Service, P.O. Box 6085, Athens, Georgia 30604, USA 4: Qualicon, Inc., A DuPont Subsidiary, Silverside Road, Wilmington, Delaware 19810, USA 5: Silliker Laboratories, 1304 Halsted Street, Chicago Heights, Illinois 60411, USA 6: National Cattlemen's Beef Association, P.O. Box 3469, Englewood, Colorado 80156, USA 7: Foodmaker, Inc., 9330 Balboa Avenue, San Diego, California 92123, USA 8: Texas American Food Service, 1301 Northpark Drive, Ft. Worth, Texas 76102, and Office of Public Health and Science, U.S. Department of Agriculture, Food Safety and Inspection Service, 1400 Independence Avenue S.W., Washington, D.C. 20250, USA 9: Office of Public Health and Science, U.S. Department of Agriculture, Food Safety and Inspection Service, 1400 Independence Avenue S.W., Washington, D.C. 20250 and Food Safety and Technology, Sara Lee Corp., Suite 300, 8000 Centerview Parkway, Cordova, Tennessee 38018, USA 10: Office of Public Health and Science, U.S. Department of Agriculture, Food Safety and Inspection Service, 1400 Independence Avenue S.W., Washington, D.C. 20250, USA
Publication date: September 1, 2002
- IAFP Members with personal subscriptions to JFP Online: To access full-text JFP or JMFT articles, you must sign-in in the upper-right corner using your Ingenta sign-in details (your IAFP Member Login does not apply to this website). The Journal of Food Protection (JFP) is a refereed monthly publication. Each issue contains scientific research and authoritative review articles reporting on a variety of topics in food science pertaining to food safety and quality. The Journal is internationally recognized as the leading publication in the field of food microbiology with a readership exceeding 11,000 scientists from 70 countries. The Journal of Food Protection is indexed in Index Medicus, Current Contents, BIOSIS, PubMed, Medline, and many others.
Print and online subscriptions are available to IAFP Members and institutional subscribers. IAFP Members with a subscription to JFP Online will have access to all available JFP and JMFT content. Online visitors who are not IAFP Members or journal subscribers will be charged on a pay-per-view basis. Membership and subscription information is available at www.foodprotection.org.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- Ingenta Connect is not responsible for the content or availability of external websites