Shelf life of ground beef patties treated by gamma radiation

• Published in: Journal of food protection Vol. 61; no. 10; pp. 1387 - 1389
• Main Authors: Roberts, W.T, Weese, J.O
• Format: Journal Article
• Language: English
• Published: Des Moines, IA International Association of Milk, Food and Environmental Sanitarians 01.10.1998
• Subjects: Animals; beef; Biological and medical sciences; Cattle; cell growth; Colony Count, Microbial; Enterobacteriaceae - growth & development; Enterobacteriaceae - isolation & purification; Food industries; Food Irradiation; Food Packaging; food safety; Fundamental and applied biological sciences. Psychology; Gamma Rays; ground beef; irradiated foods; Meat and meat product industries; Meat Products - microbiology; Meat Products - radiation effects; Meat-Packing Industry; microbial contamination; off odor; patties; Refrigeration; shelf life; Staphylococcus aureus - growth & development; Staphylococcus aureus - isolation & purification; Time Factors; Vacuum; Ionizing irradiation; Gamma irradiation; Physical dressing; Meat product; Food preservation; Shelf life; Beef; Minced meat
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-61.10.1387

The effects of irradiation on microbial populations in ground beef patties vacuum packaged and irradiated frozen at target doses of 0.0, 1.0, 3.0, 5.0, and 7.0 kGy were determined. Irradiated samples were stored at 4 or -18 degrees C for 42 days, and mesophilic aerobic plate counts (APCs) were periodically determined. Fresh ground beef (initial APC of 10(2) CFU/g) treated with 3.0, 5.0, and 7.0 kGy was acceptable (<10(7) CFU/g) for 42 days at 4 degrees C. The 1.0 kGy-treated beef samples were acceptable microbiologically (<10(7) CFU/g) after 42 days but developed an unacceptable off-odor after 21 days. Shelf life diminished in fresh ground beef patties with an initial APC of 10(4) CFU/g. Only beef patties treated with 7.0 kGy were found to be acceptable at 42 days. Beef patties treated at 1.0 and 3.0 kGy reached spoilage APC levels (>10(7) CFU/g) by day 14 and 21, respectively, whereas patties treated at 5.0 kGy did not spoil until 42 days. The nonirradiated control samples for both batches of ground beef spoiled within 7 days. Microbial counts in ground beef patties stored at -18 degrees C did not change over the 42-day period. Shelf life of ground beef patties stored at 4 degrees C may be extended with gamma radiation, especially at 5.0 and 7.0 kGy. Initial microbial load in ground beef samples was an important shelf life factor.