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.

Keywords:

• Antioxidants
• extraction technology
• health claim
• nutrients
• oil quality

Acknowledgements

The authors wish to thank Prof. Maurizio Servili and Dr. Roberto Selvaggini, Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università degli Studi di Perugia, 06126 Perugia, Italy, for providing standard samples and help in HPLC/DAD/FLD analysis. Authors are in debt with Mr. Domenico Bianchini from the Azienda Agricola “La Collina,” in Cartoceto “Le Marche” (PU), Italy, for distributing the olives in the two milling plants and for collection of oil samples.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.