Is Refrigeration Enough to Restrain Foodborne Pathogens?

Abstract

Holding foods at 5°C has traditionally been viewed as adequate to restrain the growth of foodborne pathogens. However, a group of “new” foodborne pathogens has emerged, some of which are capable of competitive growth at 5°C in foods. Bacteria fitting this criterion include Clostridium botulinum type E, Yersinia enterocolitica, enterotoxigenic Escherichia coli, Listeria monocytogenes and Aeromonas hydrophilia. A second area discussed is the effect of low temperature (5°C) on survival of foodborne pathogens. Both Campylobacter jejuni and Brucella survive for longer periods at 5°C compared to 25 or 37°C. A third area considered is the growth of certain pathogens (Salmonella, Staphylococcus aureus, Vibrio parahaemolyticus, Bacillus cereus) at temperatures slightly above 5°C up to 12°C. Hence, temperature abuse of a food could readily generate a hazard in a food. The use of refrigeration (5°C holding of a food) can no longer be deemed sufficient to keep foods safe from bacterial hazards either by growth of the “new” pathogens or increased survival. Further, even brief temperature abuse can create hazards from certain bacteria.