C. Papadopoulou et al., SURVIVAL OF ENTEROBACTERIA IN LIQUID CULTURES DURING MICROWAVE-RADIATION AND CONVENTIONAL HEATING, Microbiological research, 150(3), 1995, pp. 305-309
Bacteria in food have been reported to survive in larger numbers after
processing by microwave radiation than after conventional processing.
The bactericidal effect of a domestic microwave oven (SHARf R-7280) o
n certain pathogenic enterobacteria species was investigated in vitro,
in comparison with conventional heating (boiling). The death rates of
different nosocomial strains of Escherichia coil, Salmonella sofia, S
almonella enteritidis, Proteus mirabilis and Pseudomonas aeruginosa we
re tested. The microwave oven and the conventional heating system used
were both calibrated in order to calculate temperatures from exposure
times. For each strain duplicate samples of 25 ml of pure culture wit
h concentrations at least 10(6) cfu/ml were exposed to microwave radia
tion. An equal number of samples of the same volume and concentration
were exposed to conventional heating. Subsequently all samples were ex
amined qualitatively and quantitatively following standard microbiolog
ical procedures. The results indicate that microwaves have an efficien
t bactericidal effect on the enterobacteria in liquid cultures.