Quantity and quality of secoiridoids and lignans in extra virgin olive oils: the effect of two- and three-way decanters on Leccino and Raggiola olive cultivars

Abstract

In this investigation, 14 extra virgin olive oils (EVOOs), produced with Leccino and Raggiola olive cultivars, by a new two-way (2W) decanter were compared with 14 EVOOs produced by means of a conventional three-way (3W) decanter. The 2W EVOOs had higher phenol concentrations, as shown by high-performance liquid chromatography/diode array detection (HPLC-DAD) analysis and yielded a higher extraction of the 3,4-DHPEA-EDA (oleacein), 3,4-DHPEA-EA (oleuropein aglycone) and p-HPEA-EDA (oleocanthal). The concentrations of lignans, (+)-pinoresinol and (+)-1-acetoxypinoresinol, detected by HPLC-FLD equipment, were higher in the 2W EVOOs than they were in EVOOs produced using the 3W system. Total phenols, detected by the Folin–Ciocalteu assay, were lower than those obtained by HPLC, but they significantly correlated (p < 0.05). The antioxidant capacity (ORAC) values of 2W EVOOs were higher than those of 3W EVOOs. In conclusion, the 2W system provided high-quality phenol EVOOs and became an indispensable tool when adverse climatic conditions reduced the olive secoiridoid concentration.