Optimization of a simplified method for fruit phenolic extraction and analysis to be used in olive breeding

Phenolic compounds are generally accepted as key components of virgin olive oil with a great impact on its organoleptic and health promoting properties. However, olive phenolic components are not commonly used as quality traits in olive breeding programs mainly due to the difficulties of evaluating a large number of new genotypes with very little oil production at the early stages of breeding. In the present work, we describe and optimize a fast and reliable method for the extraction and further analysis of the main phenolic compounds found in olive fruit. The analytical methodology has been validated with the two most relevant olive varieties grown in Spain, 'Picual' and 'Arbequina', which possess very different phenolic profiles. The significant correlation found between specific phenolic compounds, or groups of phenolic compounds in the olive fruit analyzed with this method, and the phenolic content of virgin olive oil suggest that this method may be a very useful predictive tool which could prevent the selection of olive genotypes whose oils will never reach an optimum phenolic content.