Rapid detection of Salmonella in foods using real-time PCR

Abstract

Conventional methods for detection of Salmonella serovars in foods are generally time-consuming and labor intensive. A real-time PCR method has been developed with custom designed primers and a TaqMan probe to detect the presence of a 262-bp fragment of the Salmonella-specific invA gene. The method has been tested with a total of 384 field-isolated Salmonella serovars and non-Salmonella stock strains, as well as 420 U.S. Food and Drug Administration food samples, comprising a variety of food matrices. The method was highly specific in detecting Salmonella in spiked chili powder and shrimp samples, with a sensitivity of 0.04 CFU/g. In addition, the method is faster, more accurate, and less costly than the traditional U.S. Food and Drug Administration's Bacteriological Analytical Manual cell-culturing and the AOAC International-approved VIDAS methods to detect Salmonella in foods.