Fate of Escherichia coli in Nonintact Beef Steaks  during Sous-Vide Cooking at Different Holding Time and Temperature Combinations

Sous-vide cooking has increased in popularity due to ease of use, but some manufacturer recommendations for sous-vide cooking of nonintact meat products include potentially unsafe time and temperature combinations. This experiment was designed to address these con-cerns by validating a 5-log reduction of Escherichia coli in sous-vide cooked beef steaks. Beef semitendinosus steaks were inoculated externally and internally with E. coli ATCC 25922 via immersion and use of a pin pad, respectively. Individual steaks were vacuum packaged and cooked in sous-vide water baths held at 46, 51, 54, and 62°C. A 5-log reduction was reached at 51°C, 54°C, and 62°C after 258, 64.5, and 2.25 min, respectively (P < 0.01). At 46°C, cooking achieved a final 1.07-log reduction (P < 0.01) after 420 min. These results confirm the utility of U.S. Department of Agriculture, Food Safety and Inspec-tion Service guidelines (Appendix A) and raise concerns about the safety of sous-vide meat cooked at < 46°C. Further experimentation is needed with pathogenic E. coli strains during sous-vide cooking of steaks using time and temperature combinations at and below recommended Appendix A values.