Lebanon bologna raw batter was mixed
with a five-strain mixture of Escherichia coli
O157:H7 to achieve average inoculum levels of
7.79, 7.77, and 7.92 log CFU/g as deter
mined on MSA, 202, and PRSA media,
respectively. Treatment 1 consisted of a
fermentation cycle of 8 hrs at an internal
temperature (I.T.) of 80EF then 24 hrs at
100EF I.T., followed by 24 hrs at 110EF I.T.
Treatments 2, 3, and 4 included additional
heating at 115EF I.T. for 1, 2, and 5 hrs,
respectively. All heat treatments resulted in
product that was negative (<1.9 log CFU/g
detection limit) on all culture media and
negative after enrichment on mEC selective
medium. This study validates that a five-log
reduction of E. coli O157:H7 can be
achieved using the described protocol, thus
meeting USDA/FSIS requirements.
