title: Improvement of shelf-life and wholesomeness of ground beef by irradiation 1. Microbial aspects.
abstract: Various doses of ionizing radiation (cobalt-60) were used to improve the microbiological quality of commercial ground beef. The study included the isolation and identification of the natural microbial flora. The radioresistance of the individual strains was investigated. D(10) values, obtained in a saline solution, showed values ranging from 0·035 to 1·827 kGy. Treatment of ground beef with gamma radiation at doses of 1·0, 2·5 and 5·0 kGy resulted in extended shelf-life at 4°C of 4, 10 and 15 days, respectively while the control samples already exceeded 10(7) colony forming units (CFU)/g on day 0. Dominant groups of bacteria shifted from Gram-negative bacilli to Gram-positive cocci as the irradiation dose increased. Gram-negative cocci as well as yeasts and moulds also developed in greater proportion during storage of the irradiated samples.
authors: Centre de Recherches en Sciences Appliquées à I'Alimentation, Institut Armand-Frappier, 531 Boul. Des Prairies, Laval, H7N 4Z3, Canada.
authors: N
authors: N
authors: Lefebvre
authors: C
authors: C
authors: Thibault
authors: R
authors: R
authors: Charbonneau