engleski

Relationship between phenolic content and oxidative stability in dalmatian virgin olive oils.

Olive oil is a prominent source of monounsaturated fatty acids (MUFAs) due to its high oleic content, as well it's a rich source of natural antioxidants (vitamin E, polyphenols such is oleuropein and tyrosol). Its antioxidant content depends on different factors, such is cultivar, fruit ripening stage, climate conditions and olive growing techniques. Oxidative stability of olive oils is related to the ratio of monounsaturated and polyunsaturated fatty acids, and is also influenced by phenolic fraction. The aim of the study presented in this paper was to determine the fatty acid composition, total phenol content and composition of single phenol compounds and their correlation with oxidative stability of examined oils. Fatty acid content was determined by GC technique. Total phenol content was measured colorimetrically, while the single phenol composition was determined using HPLC-DAD/MSD system. Oxidative stability of oils was evaluated by OSI instrument. In this study, in all samples, very good total phenol content was detected, up to 384.33 mg/kg. Among single phenolics, the most representative was hydroxsityrosol and oleuropein aglycon. Oxidative stability data showed very good storage capacity, depending on fatty acid and phenol composition. Oxidative stability of two cultivars was correlated with their oleic/linoleic ratio, while in others it depends also on phenol composition.

olive oil; oxidative stability; phenols; fatty acid composition

nije evidentirano