Fate of Escherichia coli O157:H7 and Other Coliforms in Commercial Mayonnaise and Refrigerated Salad Dressing.

Commercial mayonnaise and refrigerated ranch salad dressing were inoculated at two levels with two strains of Escherichia coli O157:H7, a non-pathogenic E. coli , and the non-fecal coliform Enterobacter aerogenes . Results showed that at the high inoculation level (>10 colony forming units [CFU]/g) in mayonnaise stored at room temperature (ca.