The 106th General Meeting of the American Society for Microbiology (ASM) in Orlando, Florida discussed the fact that, although rare, public health officials should be aware of this possibility.
"The more we find out about the behavior of microorganisms in non-potentially hazardous foods the more we are beginning to understand that some of these foods are borderline or not consistent with the definition," said Dr. Larry Beuchat of Center for Food Safety at the University of Georgia.
Foods that, because their acidity, moisture level, or a combination of both, are incapable of supporting the growth of foodborne pathogens or toxin production without storage time and temperature controls are defined by the US Food Code as non-potentially hazardous foods. But this designation also includes foods that do not support growth but still may contain pathogenic organisms at sufficient levels to cause disease.
"For many years individuals in the public health arena would not think of orange juice as a vehicle for Salmonella. When epidemiologists would collect information on Salmonella outbreaks, high acid beverages like orange juice were not considered to even possibly be involved as carriers," said Beuchat.
At least that was the case until just a little over 10 years ago. Since the mid-1990s a number outbreaks of salmonellosis have been associated with the consumption of unpasteurized orange juice. The sudden appearance of unpasteurized orange juice as a vehicle for Salmonella could be due to a variety of reasons including a greater amount of orange juice consumed and more importation of orange products from countries that might not have sanitary guidelines or regulations as strict as the US.
It could also be due to better surveillance by public health officials and more sensitive detection methods.
"Is it new, or were we just not looking for it 20 years ago? I think it is a little bit of both," said Beuchat.
Beuchat noted that all outbreaks have been associated with unpasteurized orange juice.
His presentation was part of a large symposium organized at the ASM meeting to examine the issue of foodborne diseases from non-potentially hazardous foods.