Do the Bio-impedance Models Exhibit Pinched Hysteresis?

Recently, pinched hysteresis has been found in the electrical modelling of regular plant tissues. Usually, the biological tissues are characterized in the frequency domain using bio-impedance analyzers without investigating the time domain, which would show the pinched hysteresis. In this paper, the current-voltage analysis of some of the widely known electrical bio-impedance models is studied. The investigated models are the single dispersion Cole-impedance model, the double dispersion Cole-impedance model and the fractional-order simplified Hayden model to prove that these models can not exhibit pinched hysteresis. It is proved mathematically in this paper that there are no pinch-off points that would exist in these models. These results are verified with numerical simulations of three different plants: tomato, carrot and banana, concluding that the bioimpedance modelling needs a nonlinear element to model the pinched hysteresis in the current-voltage behaviour of these tissues. © 2020 IEEE.