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The presence of food in extra virgin olive oil (EVOO) during simultaneous storage might bring additional changes to the oil’s composition and quality. To investigate this matter, the influence of dried tomatoes on the oxidative and hydrolytic parameters, fatty acids, phenolic and volatile composition, antioxidant activity, pigments, and sensory attributes of EVOO during six months of simultaneous storage at room temperature (RT; 22 ± 2 °C) and +4 °C, was studied. Lower storage temperature reduced the hydrolytic and oxidative degradation of oils when dried tomatoes were immersed. The dried tomatoes addition did not affect the fatty acids composition of EVOO. The accelerated degradation kinetics of individual phenolic compounds and antioxidant activity of oils were influenced by the presence of dried tomatoes, being more pronounced at RT. C6 and C5 volatiles responsible for the green odour of EVOO decreased, while tomato-derived volatiles (3-methylbutanal and acetic acid) increased during simultaneous storage with dried tomatoes, especially at RT. The addition of dried tomatoes diminished the intensities of EVOO’s positive attributes (fruitiness, bitterness, and pungency) while enhancing the tomato odour attribute. This study demonstrates that the introduction of dried tomatoes significantly alters the composition and quality of EVOO when used as a storage medium.

In the present study, the influence of heating on the evolution of oxidative indices, antioxidant activity, phenolic and volatile compounds in monovarietal extra virgin olive oils (EVOOs) obtained from Leccino, Istarska bjelica, and Buža cultivars was investigated. The samples were submitted to heating in an air oven (180 °C and 220 °C), simulating usual roasting conditions typical for Mediterranean cuisine. The decreases in the oxidative indicators, phenolic and volatile compounds were more pronounced at higher heating temperatures, underlining the temperature dependency of the oxidative degradation during heating conditions. Despite this, it must be emphasized that a significant amount of phenolic compounds and antioxidative activity remained preserved after the heating treatment. Each oil cultivar showed some specificity during the course of the thermal degradation. Hydroxytyrosol acetate among phenolic compounds and octanal, (E)-2-octenal, hexanal, 3-pentanone, and 1-penten-3-one among the volatiles were underlined as possible markers of thermal oxidation. Principal component analysis revealed that the content of volatile compounds in monovarietal EVOO samples distinguished samples primarily by the heating temperature, while the changes in the phenolic compounds were cultivar-dependent aside from being influenced by the temperature of heating.