for purposes such as same day
monitoring of the effects of pasteurizing or cooking processes on
foods that are not heavily contaminated with E. coli.
The finding that E. coli subjected to relatively mild, lethal heat
treatments remained impermeable to PMA is agreeable with the
recent report of L. innocua killed by heating at 60 C being impermeable
to PMA (Løvdal et al., 2011). These findings may then be
generally applicable to other bacteria. They also suggest that other
bactericidal treatments may produce substantial fractions of dead
bacteria that are impermeable to PMA. Treatment of samples with