Evaluation of escherichia coli biotype I as a surrogate for escherichia coli 0157:H7 for cooking, fermentation, freezing, and refrigerated storage in meat processes

Abstract

Ames, Iowa 50010; and 3Department of Animal Science, Texas A and M University, College Station, Texas 77843, USA Five Escherichia coli biotype I isolates were compared with E. coli 0157.Ή7 under four common meat processing conditions. The processes that were evaluated were freezing, refrigerating, fermentation, and thermal inactivation. For each study, at least one surrogate organism was not statistically different when compared with E. coli 0157:H7. However, the four studies did not consistently show the same isolate as having this agreement. The three studies that involved temperature as a method of controlling or reducing the E. coli population all had at least one possible surrogate in common. In the fermentation study, only one isolate (BAA-1429) showed no statistical difference when compared with E. coli 0157:H7. However, the population reductions that were observed indicated the isolates BAA-1427 and BAA-1431 would overestimate the surviving E. coli 0157:H7 population in a fermented summer sausage. When all of the data from all of the surrogates were examined, it was found that isolates BAA-1427, BAA-1429, and BAA-1430 would be good surrogates for all four of the processes that were examined in this study. There was no statistical difference noted between these three isolates and E. coli 0157:H7 in the refrigeration study. These isolates resulted in smaller population reductions than did E. coli 0157:H7 in the frozen, fermentation, and thermal inactivation studies. This would indicate that these isolates would overpredict the E. coli 0157:H7 population in these three instances. This overprediction results in an additional margin of safety when using E. coli biotype 1 as a surrogate. © International Association for Food Protection.