Hydrochloric Acid Application Improves the Detection of Salmonella spp. and Escherichia coli O157:H7 in Food Samples

In this study, it was investigated whether treatment of food samples with HCl (prepared with NaCl solution) could be used instead of the pre-enrichment and enrichment steps in the ISO methods used for Salmonella spp. and E. coli O157:H7 detection in food samples. For this purpose, a total of 103 food samples were analyzed for the Salmonella spp. and E. coli O157:H7 detection with 3 different methods including ISO and 2 modified methods. In the modified methods, food samples were treated with five different HCl concentrations instead of or after the enrichment step. E. coli O157:H7 (beef meat and Turkish-style fermented sausage) and Salmonella spp. (whipped cream and instant soup powder) were detected in 2 of the food samples examined. The same results were obtained for E. coli O157:H7 and Salmonella spp. detection in food samples with 3 different methods used. However, effective HCl concentrations (range from 1/2 N to 1/10 N) varied depending on the detected pathogen and food type. The obtained results showed that the treatment of food samples with 1/10 N HCl instead of the enrichment step was effective in both Salmonella spp. and E. coli O157:H7 detection in different food samples.