"To facilitate timely intervention measures, the food industryneeds more rapid detection methods..."

Infrared sensors for rapid detection of select microbial foodborne contaminants

Investigators: Lisa Mauer (Department of Food Science), Maribeth Cousin (Department of Food Science), Jay Gore, Jean Guard-Petter, Brad Reuhs (Department of Food Science), Sivakumar Santhanakrishnan

Project Report 2005 - 2006

» Download Project Report 2005 - 2006

Project Rationale

Conventional detection methods take at least 24 to 48 hours to differentiate and identify microorganisms; therefore, measures taken to counteract food contamination must wait at least that long. To facilitate timely intervention measures, the food industry needs more rapid detection methods and a sensor able to accurately and rapidly identify low levels of microbial foodborne contaminants within food systems or culture media. We are investigating the efficacy of infrared (IR) technology as a means for rapid detection of select bacterial pathogens. To accomplish this goal, we: (a) Created a library of Fourier-transform infrared (FT-IR) spectra of bacterial cell wall components and whole cells needed for pathogen identification and differentiation. (b) Developed FT-IR methods for identification and quantification of these pathogens from water, cultural media, and select foods. This included standardizing sampling procedures, quantification methods, and spectral analysis procedures, as well as developing an overall chemometric approach for the analysis of FT-IR data. (c) Designed an IR sensor based on the most promising few-wavelength algorithms developed using FT-IR data generated from research activities in the first two objectives.

Project Objectives

  • Create a library of FT-IR spectra of bacterial cell wall components and whole cells (from Salmonella, Campylobacter jejuni, and Escherichia coli O157:H7) needed for cell identification and differentiation.
  • Develop FT-IR methods for cell identification and quantification in water, cultural media, and foods.
  • Develop a limited wavelength approach for cell identification.
  • Build and validate an IR sensor based on the most promising few-wavelength algorithm developed using FT-IR techniques selected in the first two milestones.

Project Highlights

We successfully completed the development of sample preparation techniques for FTIR spectral collection and data analysis that are able to both quantify and identify Salmonella and E. coli O157:H7 from mixtures of bacteria in culture media and select food items. To develop this approach, we evaluated a variety of sample preparation methods, FTIR data collection methods, and analytical approaches for raw spectra. Further development of this approach enabled the design of a sensor that can be used in a production or retail facility to characterize a food sample as contaminated or free of select pathogenic bacteria in less time than current methods for detection.

Annual Report


  • Maribeth Cousin
  • Jay Gore
  • Jean Guard-Petter
  • Lisa Mauer
  • Brad Reuhs
  • Sivakumar Santhanakrishnan