OLIVE OILS AND HEALTH 66 During the refining process of oils, such as those coming from seeds, most of the components of the unsaponifiable fraction are eliminated. In contrast, they are completely preserved in VOO. Furthermore, the composition of this food matrix is influenced by a number of factors (both human and natural) that determine the biosynthesis and degradation of certain components and, thus, have a decisive influence on the final compositional profile of the oil. The olive variety and ripeness, the agronomic practices, and the technological processes involved in the oil extraction are among the most significant. There are some families of minor compounds to which the scientific community has paid more attention as a consequence of the bioactivity they exhibit. In the following paragraphs, some relevant aspects of these compounds will be com mented. Phenolic compounds, are a large heterogenous chemical family with several subgroups, including simple phenols, phenolic acids, flavonoids, lignans, and secoiridoids. The latter are complex phenols, the most abundant and well-known being: oleuropein aglycone, ligstroside aglycone, oleocanthal, and oleoacein. Phenolic compounds are natural antioxidants contributing to olive oil stability against auto-oxidation, thus increasing the product’s shelf life, and playing a key role in its organoleptic propMajor compounds ≈98% Minor compounds ≈2% Monounsaturated Polyunsaturated Saturated } Phenolic compounds } Tocopherols } Phytosterols } Pentacyclic Triterpenes } Pigments } Volatile compounds Determining factors for VOO composition ü Variety ü Pedo-climatic features ü Agronomic practices ü Processing methods Fatty acid distribution in triglycerides VIRGIN OLIVE OIL COMPOSITION Figure 3.3 Virgin olive oil composition. Diagram depicting virgin olive oil (VOO) composition identifying the major (saponifiable) and minor (unsaponifiable) fractions and some factors affecting VOO composition. ■ ■ ■ ...
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