Electrical Impedance Method for Determining Microbial Quality of Foods

  • R. Firstenberg-Eden


Impedance is the opposition to flow of an alternating electrical current in a conducting material. When monitoring the growth of microorganisms, the conducting material is a microbiological medium. Impedance changes occur in the medium as its chemical composition changes due to growth and metabolic activity of microorganisms. During growth, microorganisms convert larger molecules to smaller, more mobile metabolites, thus changing the impedance. When the microbial population reaches a threshold fo 106–107 cells/ml an exponential change in impedance signal is observed. The time required for this exponential change is inversely proportional to the initial cell concentration and is defined as impedance detection time (IDT)


Electrical Impedance Orange Juice Plate Count Impedance Method Brilliant Green 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • R. Firstenberg-Eden
    • 1
  1. 1.Bactomatic Inc.PrincetonUSA

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