The experiments have been performed for the recognition of
several kinds of juice odours and were especially directed for find-
ing the difference between the juices even if they belonged to the
same brand. As a first step, Radar-like plots with unitary radius
were used to observe whether pattern differences (i.e. fingerprints)
were developed between juice samples. Fig. 1 shows a representa-
tive case. To construct these plots, the values of TGS steady-state
conductance were divided by the value corresponding to sensor
showing the maximum response for each type of fruit juice. This
helps to easily visualise the differences amongst typical response
patterns. As can be seen, there were significant differences and
similarities in the fingerprint of juices. For instance, A_Mango,
A_Pear, B_Pear and D_Mango were detected, with the highest sen-
sitivity by the TGS 825 sensor and as a consequence these juices
possessed the same shape, however, D_FruzzyOrange, D_Multivi-
tamins and D_Pear were best detected by the TGS 842 sensor
and had similar signatures which were different to the remaining
juices.