An easy-to-perform, culture-free Campylobacter point-of-management assay for processing plant applications

J Appl Microbiol. 2020 Mar;128(3):620-629. doi: 10.1111/jam.14509. Epub 2019 Dec 4.

Abstract

Aims: Current culture-based methods for detection and determination of Campylobacter levels on processed chickens takes at least 2 days. Here we sought to develop a new complete, low-cost and rapid (approximately 2·5 h) detection system requiring minimal operator input.

Methods and results: We observed a strong correlation between culture-based cell counts and our ability to detect either Campylobacter jejuni or Campylobacter coli by loop-mediated isothermal amplification from the same samples. This knowledge was used to develop a rapid and simple five-step assay to quantify Campylobacter, which was subsequently assessed for its specificity, reproducibility and accuracy in quantifying Campylobacter levels from processed chickens. The assay was found to be highly specific for C. jejuni and C. coli and was capable of distinguishing between samples that are either within or exceeding the industry set target of 6000 Campylobacter colony forming units (CFU) per carcass (equivalent to 12 CFU per ml of chicken rinse) with >90% accuracy relative to culture-based methods.

Conclusions: Our method can reliably quantify Campylobacter counts of processed chickens with an accuracy comparable to culture-based assays but provides results within hours as opposed to days.

Significance and impact of the study: The research presented here will help improve food safety by providing fast Campylobacter detection that will enable the implementation of real-time risk management strategies in poultry processing plants to rapidly test processed chickens and identify effective intervention strategies. This technology is a powerful tool that can be easily adapted for other organisms and thus could be highly beneficial for a broad range of industries.

Keywords: Campylobacter; diagnostic; food-safety; isothermal amplification; poultry.

MeSH terms

  • Animals
  • Campylobacter / isolation & purification*
  • Campylobacter coli / genetics
  • Campylobacter coli / isolation & purification
  • Campylobacter jejuni / genetics
  • Campylobacter jejuni / isolation & purification
  • Chickens / microbiology*
  • Food-Processing Industry
  • Nucleic Acid Amplification Techniques / methods
  • Reproducibility of Results