Exploration of genetic resources to improve the functional quality of virgin olive oil

- Olive species showed a large degree of variability in terms of fruit and oil phenolics.
- Core-36 olive fruit phenolics displays a variability interval of 3213-36312 µg/g fruit.
- Core-36 olive oil presented a variability interval of 26-1410 µg/g oil.
- Phenolics in the olive fruits and oils were highly and significantly correlated.

Phenolics are claimed to be one of the main responsible for the health benefits associated to the long term consumption of virgin olive oil (VOO). The variability of the phenolic composition was studied in an olive cultivar core collection which holds an extensive genetic diversity. The most abundant VOO phenolics were the secoiridoid derivatives resulting from the hydrolysis of oleuropein, ligstroside and demethyloleuropein present in the fruit, which showed to be on average their main phenolic glucosides. Total phenolic compounds in the fruits and the oils were, in general, significantly and positively strong correlated (r = 0.82) with p < 0.001. Thus, the fruit phenolic content seems to be the main factor determining the synthesis of VOO phenolics during oil extraction. Data on phenolic composition would be of interest for the selection of optimal parents in olive breeding programs with the aim of obtaining new cultivars with improved functional quality.