Panel tests and oil categorisation

When Panel testings are performed, the primary goal of the organoleptic evaluation is to determine the presence of defects in the oils; these defects could easily be generated by the inappropriate storage of fruits or by their improper handling or processing. The attributes used to identify potential defects (such as Fusty, Musty-humid, Winey-vinegary, Metallic and Rancid) are assessed by qualified staff who calculate the median value of the perceived attribute intensity on a continuous scale that ranges from absent to strong (from 0 to 10). The secondary goal of the Panel is to measure the intensity of the positive attributes of the oil. The positive attributes are Fruity, Bitter and Pungent, and their assessment is carried out by means of the same continuous scale.

This sensory evaluation, together with the chemical and physical analysis, lead to the categorisation of the different grades of olive oil, which are: extra virgin, with a median of defects equal to zero and a median of fruitiness greater than zero; virgin, with a median of defects greater than zero but lower than 3.5 and a median of fruitiness greater than zero; or lampante, which is not edible as it is, having either a median of defects greater than 2.5 or else a median of defects lower than 3.5 but a median of fruitiness equal to zero.