Biophenols and flavor in extra virgin olive oils from San Juan province (Argentina)

Abstract

In this work, phenolic compounds and their relationship with flavor in Arbequina, Changlot Real and Coratina cultivars extra virgin olive oils from the San Juan province (Argentina) in the 2012 and 2013 harvests were studied. In 2013, the harvesting was brought forward by 15-17 days. The total and individual biophenols were analyzed by HPLC-UV. A taste panel recognized by the International Olive Council (IOC) carried out the sensory analysis. Oxidative stability was measured by accelerated oxidation assays using Rancimat equipment. The oils obtained in 2013 from the three cultivars had higher biophenol contents and particularly higher contents of secoiridoid and derivatives. The positive attributes (fruitiness, bitterness and pungency) of the oils were more harmonious in the three cultivars in 2013 by enhancing the complexity with a wide range of green descriptors. The oxidative stability indices of the oils were also higher in the three cultivars in 2013. The multiple linear regression model suggested that oleuropein aglycone, aldehyde and hydroxilic form (3,4-DHPEA-EA) was the main contributor (65.5 %) to bitterness, while decarboxymethyl ligstroside aglycone, dialdehyde form (p-HPEA-EDA), besides reducing bitterness, was the major contributor to pungency (52.2 %). Among simple phenols, o-coumaric acid contributed to bitterness (2.3 %), and tyrosol (6.3 %) and tyrosyl acetate (3.3 %) were related to pungency.