Measurement of the electrical conductivity:
The electrical conductivity increases considerably by increasing content of water of the grain and the measurement of the electrical conductivity can be carried out as measurement of the resistance of the grain sample e.g. by measuring the current at constant voltage according to Ohm´s law or by a bridge circuit.
Measurement of the dielectric constant:
The high dielectric constant of water is a useful measure for the content of water of a grain sample. The capacity of a capacitor like measuring cell is measured with the grain sample under test as dielectric.
Measurement of the absorption of electromagnetic radiation:
In the NIT procedure (near infrared transmission) the absorption of electromagnetic radiation transmitting the unshred sample is determined in the region of the near infrared. The absorption is in relation not only to the content of water but also to a series of other ingredients (protein, e.g.).