Use of a commercial tissue dissociation system to detect Salmonella-contaminated poultry products

Authors: Armstrong, Cheryl; He, Yiping; Chen, Chinyi; Counihan, Katrina; Lee, Joseph - Joe; Reed, Sue; Capobianco, Joseph

Submitted to: Analytical and Bioanalytical Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2023
Publication Date: 4/14/2023
Citation: Armstrong, C.M., He, Y., Chen, C., Counihan, K.L., Lee, J., Reed, S.A., Capobianco Jr, J.A. 2023. Use of a commercial tissue dissociation system to detect Salmonella-contaminated poultry products. Analytical and Bioanalytical Chemistry. https://doi.org/10.1007/s00216-023-04668-w.
DOI: https://doi.org/10.1007/s00216-023-04668-w

Interpretive Summary: While significant advancements have been made in sensors for rapid pathogen detection, the process of bacterial separation remains a bottleneck in the process. Developing assays to detect pathogens in food is especially challenging due to the irregular distribution of dilute microorganisms throughout the complex mixture. To further complicate detection, microorganisms can attach to surfaces and/or be contained within the matrix. A commercial system for mechanical and enzymatic digestion of skeletal muscle was evaluated to detect the prevalence of Salmonella in raw chicken legs using conventional laboratory screening diagnostics. The results showed that both microbiological and molecular methods identified lower levels of contamination in raw poultry when the samples were treated with the commercial digestive treatment compared to stomaching, a standard sample treatment process currently utilized by commercial and regulatory food safety laboratories.

Technical Abstract: Successful detection of bacterial pathogens in food can be challenging due to the physical and compositional complexity of the matrix. Different mechanical/physical and chemical methods have been developed to separate microorganisms from food matrices to facilitate detection. The present study benchmarked a commercial tissue digestion system that applies both chemical and physical methods to separate microorganisms from tissues against stomaching, a standard process currently utilized by commercial and regulatory food safety laboratories. The impacts of the treatments on the physical properties of the food matrix were characterized along with the compatibility of the methods with downstream microbiological and molecular detection assays. The results indicate the tissue digestive system improves the bacterial recovery from the food matrix in a manner that does not adversely affect assays dependent upon microbial growth or amplification of nucleic acids. Collectively the results demonstrate that the technique enables detection of pathogens at lower levels of contamination using current industry standard technologies.