Influenza sugli indici spettrofotometrici derivativi di fenomeni fotossidativi dovuti alla presenza di clorofilla e caroteni negli oli vegetali

The presence of chlorophyll in pressure olive oils initiates a series of photooxidative phenomena consequent on the transformation of oxygen from the ground triplet state to the single state. It involves a strong oxidation reaction, the effects of which modify the derivative spectrophotometric indices. In this paper we have evaluated the incidence of these phenomena on the variation of the Δ'K241 over time because this index is important in order to define the oldness of a vegetable oil. It has been possible to confirm that the contemporaneous presence of high quantities of chlorophyll and light makes the value of the AK241 increase sensibly. Over time this action goes down in consequence of the progressive discolouration of the sample and/or because of the contemporaneous presence of carotenes that have, instead, a decided quenching effect tending to contrast the photooxidative action carried out by the chlorophyll.