HIGH-PRESSURE EFFECTS ON LIPID OXIDATION OF EXTRA VIRGIN OLIVE OILS AND SEED OILS

High pressure treatment was applied to extra virgin olive oils and to seed oils in order to verify if and to what extent modifications in th e lipidic fraction can occur. Six different extra virgin olive oils an d five different seed oils (grape-stone, sunflower, soybean, peanut, m aize) were treated at 700 MPa for 10 minutes at room temperature. Diff erent analytical parameters (peroxide value, para-anisidine value, ran cimat test, volatile hydrocarbons) were measured to study the oxidativ e stability of the treated oils. The application of high pressure at t hese operating conditions produced changes in the p-anisidine values, but not in the peroxide values and volatile hydrocarbons of the oil sa mples. As expected, in all cases, the olive oils were more resistant t o oxidation than the seed oil samples. It is necessary to point out th at the effects of high pressure treatment on oils depend on their orig in, composition, initial quality and age.