Assessment of beef meat aging using impedance spectroscopy

The aim of the paper is to assess the feasibility of impedance measurements for meat aging detection. The carried investigations are dedicated to the aging of the meat of beef. An investigation was carried out for the detection of the age of meat using 2 cases of storage in the fridge, unpacked meat, exposed in the air of the fridge (Up) and vacuum-packed meat, conserved in closed box (Vp). The measurements show a depressed semicircle in the admittance plane similar to the equivalent circuit consisting of a combination of a Constant Phase Element (CPE) and two resistors. The resistance R_E various is directly proportional to meat volume resistivity. The volume resistivity is constant for Vp meat, this is due to the conservation of the same situation in the surface of contact with the electrode, this situation change for the Up meat, the volume resistivity is increasing in a linear way because the surface of contact with electrode become more dry over time. The change due to R_ct is inversely proportional to the factor number of electrons involved and exchange current. The factor n.i₀ decreases over time for the Up meat, This is consistent because when the meat becomes drier, the loss of liquids causes the decrease of conductivity and proportionally the decrease of the number of electrons involved and the exchange current. For the second case (Vp), the humidity causes the decrease of the number of electrons involved and the exchange current. The impedance is inversely proportional to the double layer capacitance that is consistent with the experiments. The impedance increase for the Up meat and decrease in the second case. The change due to Cdl is directly proportional to the change of meat permittivity ε_r.