Survival of Escherichia coli O157 : H7 in buttermilk as affected by contamination point and storage temperature

The effects of contamination point (during fermentation versus postfermenta tion) and storage temperature (5 and 12 degrees 0) were determined for surv ival of Escherichia coli O157:H7 in fermented, buttermilk. E. coli O157:H7 was recovered from buttermilk inoculated during fermentation for 22 days an d in buttermilk inoculated postfermentation for 32 days. For storage temper atures of 5 and 12 degrees C, D-values were lower for E. coli O157:H7 inocu lated during fermentation (2.5, 2.2 days) than postfermentation (5.6, 4.8 d ays) (P < 0.05). Developed acidity in inoculated buttermilks was not differ ent from controls (P > 0.05). The extended recovery of viable enterohemorha gic E. coli O157:H7 from both processing scenarios indicates that the prese nce of E. coli O157:H7 in buttermilk is not limited to postprocessing conta mination.