Study of Lignans as Potential Varietal Markers of Virgin Olive Oils

The profile of the phenolic component of virgin olive oils depends on a wide number of factors such as the olive variety; although it is true that the phenolic profile of each variety may not be enough for the identification of samples obtained from different varieties. Several research studies related to the characterization of virgin olive oils produced from different varieties have been published; the authors in all these cases wanted to find potential markers for the geographical origin or the olive fruit variety. In previous works, several scientist studied the phenolic acids as marker and other considered whole phenolic profile by statistical multivariate the use of phenolic compounds for assessment of olive oil cultivars is not reliable. In fact, these minor components of oils are influenced not only by the olive cultivar, but also by climatic and environmental conditions, agronomic practice and technological process. It has been underlined that several phenolic compounds such as lignans showed an high resistance to oxidation induced during storage or thermal treatment in comparison to other phenolic compounds. For these reasons, as we are previously reported, lignans appear less affected by external factors because these compounds do not perform a noticeable antioxidant activity. In particular, the lignans that showed this high resistance are the ones derived from the combination of two phenylpropanoid (C6-C3) units; this compounds are broadly considered as representatives of phytoestrogens a group of compounds which have been shown to act as modulators of the mammalian hormonal system.