Citrobacter braakii Yield False-Positive Identification as Salmonella, a Note of Caution

Foods. 2021 Sep 14;10(9):2177. doi: 10.3390/foods10092177.

Abstract

Background: Globally, Salmonella enterica is one of the leading causes of foodborne illness in humans. Food of animal origin is obligatorily tested for the presence of this pathogen. Unfortunately, in meat and meat products, this is often hampered by the presence of background microbiota, which may present as false-positive Salmonella.

Methods: For the identification of Salmonella spp. from meat samples of beef, pork, and poultry, the authorized detection method is PN-EN ISO 6579-1:2017-04 with the White-Kauffmann-Le Minor scheme, two biochemical tests: API 20E and VITEK II, and a real-time PCR-based technique.

Results: Out of 42 presumptive strains of Salmonella, 83.3% Salmonella enterica spp. enterica, 14.3% Citrobacter braakii, and 12.4% Proteus mirabilis were detected from 180 meat samples.

Conclusions: Presumptive strains of Salmonella should be identified based on genotypic properties such as DNA-based methods. The aim of this study was the isolation and identification of Salmonella spp. from miscellaneous meat sorts: beef, pork, and poultry.

Keywords: Citrobacter braakii; Salmonella spp.; beef; meat; pork; poultry.