The influence of beef quality characteristics on the internalization and thermal susceptibility of Shiga toxin-producing Escherichia coli (STEC) in blade-tenderized beef steaks

Meat Sci. 2015 Dec:110:85-92. doi: 10.1016/j.meatsci.2015.06.014. Epub 2015 Jul 2.

Abstract

The risk of Shiga toxin-producing Escherichia coli (STEC) survival in blade-tenderized beef is a concern for beef processors. This study evaluated the internalization and post-cooking survival of individual STEC serogroups (O157:H7, O26, O45, O103, O111, O121, and O145) in blade-tenderized beef steaks with different quality traits. Strip loins representing four combinations of USDA Quality Grade (Choice or Select) and pH category (High pH or Normal pH) were inoculated (10(6)logCFU/cm(2) attachment) with individual STEC serogroups before storage (14 days), blade tenderization, and cooking (50, 60, 71, or 85°C). Serogroup populations on raw steak surfaces and internal cores were determined. Rapid-based methods were used to detect the internal presence of STEC in cooked steaks. Internalization and post-cooking survival varied among STECs. All serogroups, except O45 and O121, were detected in the internal cores of steaks cooked to 50°C, while O103, O111, and O145 STEC were detected in steaks cooked to 50, 60, and 71°C.

Keywords: Beef; Blade tenderized; Cooking; Internalization; Non-intact; STEC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Cooking*
  • Food Microbiology*
  • Hot Temperature*
  • Humans
  • Hydrogen-Ion Concentration
  • Red Meat / classification
  • Red Meat / microbiology*
  • Serogroup*
  • Shiga-Toxigenic Escherichia coli / growth & development*