U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
Date of this Version
2005
Citation
Journal of Muscle Foods 16 (2005) 342–353.
Abstract
The efficacy of hydrodynamic pressure (HDP) treatment for inactivation of Escherichia coli O157:H7 in blade-tenderized beef steaks was studied. Beef steaks (N = 48) were inoculated with a five-strain cocktail of Escherichia coli O157:H7 and treated with blade tenderization (BT), HDP or a combination of BT followed by HDP (BTH). Control and treated steaks were cooked to 54.4C (undercooked), 62.8C (medium rare) and 71.1C (medium) on open-hearth Farberware grills. HDP treatment reduced E. coli O157:H7 populations by 0.3 log10 cfu/g, which was not different (P> 0.05) from untreated controls. At each endpoint cooking temperature, E. coli O157:H7 survival was always higher in BT-treated steaks than in untreated steaks cooked to corresponding temperatures. This could be due to migration of surface bacteria to the interior of the muscle thereby protecting bacteria from the lethality of heat. E. coli O157:H7 populations in BTH-treated steaks cooked to 71.1C were nondetectable and were significantly different from BT-treated steaks cooked to 71.1C. Results suggest that BT of intact beef muscle does transfer surface bacteria to the interior of the muscle, which would necessitate a combination of elevated cooking temperatures (>71.1C) and a treatment like HDP for inactivation of bacteria.
Comments
This article is a U.S. government work, and is not subject to copyright in the United States.