Olive Oil Sensory Analysis as a Tool to Preserve and Valorize the Heritage of Centenarian Olive Trees.

Nuno Rodrigues,José Alberto Pereira,Paula Baptista,António M Peres

doi:10.3390/plants11030257

Nuno Rodrigues, José Alberto Pereira + Show 2 more

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https://doi.org/10.3390/plants11030257

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Abstract

In inland areas of Portugal and some regions of the Mediterranean basin, olive production is based on traditional olive groves, with low intensification, local cultivars, aged plants, and centenarian trees. These plants play a key role in the ecosystem, contributing to carbon sequestration and possessing a high genetic diversity, particularly important for selecting cultivars more resistant to climatic changes. Appreciation of the value of this genetic diversity implies genetic, morphological, and physicochemical characterization of centenarian trees, which is expensive and time-consuming. Sensory evaluation is also of utmost importance. Thus, in this study, centenarian olive trees were selected in the Côa Valley region, a UNESCO World Heritage site. The descriptive sensory profile of their extracted olive oils was established and used to cluster the oils, using hierarchical clustering analysis, and consequently the olive trees, into five groups with similar intensities of perceived olfactory–gustatory attributes. Each cluster revealed olive oils with unique sensory patterns, presumably due to similarities of the olive trees, confirming the potential of the proposed screening approach. The identification of sensorially homogeneous oil-tree groups would reduce the number of specimens needed for subsequent morphological, genetic, and chemical characterization, allowing a cost-effective and robust future evaluation procedure.

Highlights

The olive tree is one of the most ancient cultivated crops in the Mediterranean basin.This plant is well-adapted to this region, where around 90% of the world’s production of olive oil is concentrated [1]
From the 150 centenarian olive trees selected in the Côa Valley region, olive oils were only extracted from the olives collected from each of 96 trees, from which a sufficient amount of olives could be harvested
It should be noted that the perceived sensations, as well as the intensity ranges found, are, in general, in agreement with those reported in the literature for Moroccan and Tunisian olive oils [27,28], as well as for Portuguese oils extracted from minor cultivars of centenarian olive trees [2,20]

Summary

Introduction

The olive tree is one of the most ancient cultivated crops in the Mediterranean basin.This plant is well-adapted to this region, where around 90% of the world’s production of olive oil is concentrated [1]. In today’s climate change conditions, the contribution to carbon sequestration could be considered one of the most important of the ecosystem benefits provided by traditional olive groves Due to their long life cycle, permanent fruit trees, such as centenarian olive trees, potentially sequester a high amount of atmospheric carbon accumulated in their organs, namely the trunk, branches, and roots [5]. Considering the relationship between the genetic component and sensory characteristics, the use of the sensory profile of olive oils together with statistical techniques can be seen as a practical and useful tool for identifying groups of plants (i.e., centenarian trees) with similar characteristics, reducing the number of unknown specimens that must be fully characterized. In this study, centenarian olive trees from the Côa Valley region (Northeast Portugal) were selected, and the sensory profiles of the extracted olive oils were evaluated by a sensory panel and further statistically analyzed to establish groups of olive oils with unique sensory characteristics, which in the future will allow identification of a reduced number of centenarian olive trees for systematic genetic, morphological, and physicochemical characterization

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Results

Conclusion