Chapter 73 - The Bioavailability of Olive Oil Phenolic Compounds

Abstract

The beneficial effects of olive oil on cardiovascular risk factors are now recognized and often only attributed to its high levels of monounsaturated fatty acids (MUFA). Olive oil is, however, more than a MUFA fat. Olive oil is a functional food, which besides having a high level of MUFA contains other minor components with biological properties. The content of the minor components of an olive oil varies, depending on several conditions such as the cultivar, climate, ripeness of the olives at harvesting, and the processing system employed to produce the olive oil. Three types of olive oil are currently present on the market: virgin, ordinary, or pomace. Virgin olive oils are produced by direct pressing or centrifugation of the olives, among them those with an acidity greater than or equal to 3.3 degrees (2 degrees in the European Union) are submitted to a refining process in which some components, mainly phenolic compounds, and to a lesser degree squalene, are lost. By mixing virgin and refined olive oil, an ordinary olive oil (olive oil, UE 1991) is produced and marketed. After virgin olive oil production, the rest of the olive drupe and seed is processed and submitted to a refining process, resulting in pomace olive oil, to which a certain quantity of virgin olive oil is added before marketing. The minor components of virgin olive oil are classified into two types: the unsaponificable fraction, defined as the fraction extracted with solvents after the saponification of the oil, and the soluble fraction, which includes the phenolic compounds. The major phenolic compounds in olive oil are (1) simple phenols, (2) secoiridoids, and (3) polyphenols.