Fate of Shiga Toxin-Producing Escherichia coli (STEC) and Salmonella during Kosher Processing of Fresh Beef

Abstract

Traditional kosher meat processing involves the following steps after slaughtering: soaking with water to remove blood, salting to help draw out more blood, and rinsing to remove salt. However, the impact of the salt used on foodborne pathogens and beef quality is not well understood. The objectives of the current study were to determine the effectiveness of salt in reducing pathogens in a pure culture model, on surfaces of inoculated fresh beef during kosher processing, and the effect of salt on beef quality. The pure culture studies indicated that the reduction of E. coli O157:H7, non-O157 STEC, and Salmonella increased with increasing salt concentrations. With salt concentrations from 3 to 13%, salt reduced E. coli O157:H7, non-O157 STEC, and Salmonella ranging from 0.49 to 1.61 log CFU/mL. For kosher processing, the water-soaking step did not reduce pathogenic and other bacteria on the surface of fresh beef. Salting and rinsing steps reduced non-O157 STEC, E. coli O157:H7, and Salmonella ranging from 0.83 to 1.42 log CFU/cm2, and reduced Enterobacteriaceae, coliforms, and aerobic bacteria by 1.04, 0.95, and 0.70 log CFU/cm2, respectively. The salting process for kosher beef resulted in reducing pathogens on the surface of fresh beef, color changes, increased salt residues, and increased lipid oxidation on the final products.