Detection of Salmonella spp., Salmonella Enteritidis, Salmonella Typhi and Salmonella Typhimurium in cream cakes by polymerase chain reaction (PCR)

Abstract

The aims of this study were: (i) to determine the incidence of Salmonella spp. by conventional culture methods in cream cakes, (ii) to detect invA gene by PCR for the confirmation of the isolates, (iii) to analyze isolates for S. Enteritidis, S. Typhi, and S. Typhimurium by PCR based on Sdf I, ViaB, Spy gene sequences, respectively, and (iv) to identify isolates in comparison to the reference strain by DNA sequence analysis. A total of 81 unpackaged cream cake samples were obtained from different patisseries in Hatay, Turkey. Salmonella spp. was detected in 13 (16%) out of 81 cream cake samples by the conventional culture method. A total of 45 isolates from the 13 positive samples were confirmed as Salmonella spp. by PCR. Homology among the reference strain and isolates and homology within the isolates was found to be 98.97-100%. Cream cake samples analyzed in this study were found to be contaminated with Salmonella, thus posing a potential health hazard for the consumer. To protect public health, food safety management systems such as HACCP, GMP and GHP could be carried out in cream cake production.