Sunday 4 January 2015

Characterisation of extra virgin olive oils from Galician autochthonous varieties and their co-crushings with Arbequina and Picual cv.

Food Chemistry (2015) 176, 493-503

The current trend of the olive oil market is the production of high quality extra from traditional minor olive varieties with peculiar and differentiated characteristics (especially with respect to the aromatic and phenolic composition). In this way, the interest of Galician oil producers (NW Spain) in recovering old autochthonous Local olive fruits has increased substantially in recent years. In order to investigate the potential of the Local olives by either producing high quality monovarietal oils or mixing with the most widespread olives in Galicia (Arbequina and Picual cv.), quality indices, and fatty acid composition as well as volatile and phenolic profiles were determined and compared. All EVOOs studied in this work can be considered as "extra virgin olive oil" due to quality indices fell within the ranges established in legislation. Picual and Local olive oils as well as those resulting from their co-crushing reach values which are required by EU legislation to add the specific health claim on the oil label. Co-crushing Picual:Local (80:20) provided a significant enhancement of grass and apple nuances and a decrease of banana notes with respect to Picual oils. The co-crushing process improved sensory and health properties of Picual extra virgin olive oils. The effect of co-crushing on phenolics, ester volatiles and banana nuances cannot be easily modulated, contrary to quality indices and fatty acid composition, both changing linearly in strict correlation with the fruit mass ratio.