| abstract |
A method and an apparatus are described for testing the condition of foods, particularly fish. It has been found that the dielectric properties of some foods vary with time and consequently that the electrical quality factor and phase angle of a food sample are indicative of the amount of spoilage of the food. A probe comprising two pairs of electrodes is described for use in measuring the phase angle of a sample. The construction of the probe and the apparatus coupled thereto prevents interfacial polarization where one pair of electrodes contact the sample, and hence one important source of error is overcome. The phase angle is found by passing a current through the sample and measuring the relative phase of the current and of a potential sensed between the electrodes of the said pair. |