Device for detecting material properties of a medium, with - a measuring device including a sensor device which is in contact with the medium, and an actuator for driving the sensor device with signals of a predetermined frequency range, and - a control device for controlling the operation of the measuring device and setting the predetermined frequency range, wherein - the actuator is provided for determining the course of the impedance Z of the medium corresponding to the predetermined frequency range depending on the frequency, and for emitting a basic impedance characteristic curve including a plurality of characteristic points (P1 to P4), and - the control device is provided for evaluating the basic impedance characteristic curve, and is provided for: (a) determining a respective local frequency range of the basic impedance characteristic curve around one respective characteristic point, (b) repeating the previous determination for at least a predetermined number of the plurality of characteristic points of the basic impedance characteristic curve, (c) determining the frequency of the position of a respective characteristic point by an actual measurement in each local frequency range, and (d) determining the properties of the medium from the frequency of the position of the respective characteristic points according to (c) from the actual measurement in connection with previously stored reference values and generating a result signal with respect to the properties of the medium, and wherein (e) the characteristic points (P1 to P4) are provided in the form of discrete measurement points at predetermined frequencies within the frequency range, and f) the respective local frequency ranges are determined as a predetermined frequency range smaller or larger than the frequency of the respective characteristic point (P1 to P4) of the basic impedance characteristic curve. - a measuring device including a sensor device which is in contact with the medium, and an actuator for driving the sensor device with signals of a predetermined frequency range, and - a control device for controlling the operation of the measuring device and setting the predetermined frequency range, wherein - the actuator is provided for determining the course of the impedance Z of the medium corresponding to the predetermined frequency range depending on the frequency, and for emitting a basic impedance characteristic curve including a plurality of characteristic points (P1 to P4), and - the control device is provided for evaluating the basic impedance characteristic curve, and is provided for: (a) determining a respective local frequency range of the basic impedance characteristic curve around one respective characteristic point, (b) repeating the previous determination for at least a predetermined number of the plurality of characteristic points of the basic impedance characteristic curve, (c) determining the frequency of the position of a respective characteristic point by an actual measurement in each local frequency range, and (d) determining the properties of the medium from the frequency of the position of the respective characteristic points according to (c) from the actual measurement in connection with previously stored reference values and generating a result signal with respect to the properties of the medium, and wherein (e) the characteristic points (P1 to P4) are provided in the form of discrete measurement points at predetermined frequencies within the frequency range, and f) the respective local frequency ranges are determined as a predetermined frequency range smaller or larger than the frequency of the respective characteristic point (P1 to P4) of the basic impedance characteristic curve. (a) determining a respective local frequency range of the basic impedance characteristic curve around one respective characteristic point, (b) repeating the previous determination for at least a predetermined number of the plurality of characteristic points of the basic impedance characteristic curve, (c) determining the frequency of the position of a respective characteristic point by an actual measurement in each local frequency range, and (d) determining the properties of the medium from the frequency of the position of the respective characteristic points according to (c) from the actual measurement in connection with previously stored reference values and generating a result signal with respect to the properties of the medium, and wherein (e) the characteristic points (P1 to P4) are provided in the form of discrete measurement points at predetermined frequencies within the frequency range, and f) the respective local frequency ranges are determined as a predetermined frequency range smaller or larger than the frequency of the respective characteristic point (P1 to P4) of the basic impedance characteristic curve.