Development of a Colorimetric, Second Generation Nucleic Acid Hybridization Method For Detection of Salmonella in Foods and a Comparison With Conventional Culture Procedure


  • Presented at the 49th Annual Meeting of the Institute of Food Technologists, Chicago, IL June 26-29, 1989.

  • The authors express their sincere appreciation to M. Ottaviani, T. Pitman, A. Shah, A. Whilby, and K. Whippie for their technical assistance.


A new, highly specific colorimetric DNA hybridization method (cDNAH) for detection of Salmonella in foods was developed. It detected 355/362 strains representing 206/213 serovars of Salmonella, and showed no cross-reactivity with 32 different non-Salmonella species, including a variety of Enterobacter and Citrobacter species. The cDNAH method was compared with the BAM/AOAC culture method in two studies: (1) with 20 different inoculated and uninoculated foods overall agreement between the two methods was 99%. (2) with naturally contaminated foods at two independent sites agreement with culture was 99.8% where 9/404 samples were positive for Salmonella.