Comparison and integration of arrays of quartz resonators and metal-oxide semiconductor chemoresistors in the quality evaluation of olive oils

Olive oil analysis is considered as a promising application of electronic noses. In this paper, two electronic noses, based on different sensor technologies (quartz resonators and metal-oxides chemoresistors) are applied to the measure of samples of olive oils of different qualities and values. Among them, samples of oil produced from organically fanned olives have also been measured. While both the sensor systems provided very similar images for the commercial oils defining a sort of quality growing direction in their principal component analysis score plots, the organically farmed product has been differently interpreted by the two arrays. Merging of data, both at high and low abstraction level, shown that the co-operation of the two sensor arrays identified the organically farmed product different from the commercial samples. Details about the single sensors behavior, and the option of sensors data fusion will be illustrated and discussed.