Heat and acid sensitivity of motile Aeromonas: a comparison with other food-poisoning bacteria.
The present study was undertaken to compare the heat and acid sensitivity of aeromonads with those of other food-poisoning bacteria. It became obvious that aeromonads were more sensitive to heat than Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella typhimurium. Aeromonads were killed in peptone water within 2 min at 55 degrees C, while the other bacteria survived heating at 55 degrees C for more than 15 min. Aeromonas cells were also less resistant to heat in hamburger steaks. These findings suggest that Aeromonas infection can easily be prevented by heat treatment, although correct handling of food is required to avoid recontamination since aeromonads are very common in various kinds of food. E. coli, S. aureus and S. typhimurium cells survived in buffer at pH 3.2 and in foods seasoned with vinegar. By contrast, Aeromonas cells were found to be highly sensitive to acid. However, the resistance of Aeromonas to acid may be sufficient to allow it to infect the gastrointestinal tract since Vibrio parahaemolyticus, which causes numerous outbreaks of food-poisoning every year in Japan, was susceptible to acid to the same extent as Aeromonas.
Nishikawa
Y
Y
Department of Epidemiology, Osaka City Institute of Public Health and Environmental Sciences, Japan.
Ogasawara
J
J
Kimura
T
T
D000085:Acetates / Q000494:pharmacology; D019342:Acetic Acid; D000333:Aeromonas / Q000187:drug effects / Q000254:growth & development; D000818:Animals; D004530:Egg Yolk / Q000382:microbiology; D004926:Escherichia coli / Q000254:growth & development; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D005517:Foodborne Diseases / Q000517:prevention & control*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008460:Meat / Q000382:microbiology; D012486:Salmonella typhimurium / Q000254:growth & development; D013211:Staphylococcus aureus / Q000254:growth & development; D013997:Time Factors; D014736:Vibrio parahaemolyticus / Q000254:growth & development
D000085:Acetates; D019342:Acetic Acid