Pigments in extra virgin olive oils produced in different mediterranean countries in 2014: Near UV-vis spectroscopy versus HPLC-DAD

- Pigments in EVOOs are quantified by HPLC and near UV-vis absorption spectroscopy.
- EVOOs were produced from olives harvested in four European countries in 2014.
- The two methods used to quantify pigments are validated and compared.
- Principal component analysis (PCA) is applied to analyze pigments' content in EVOOs.
- Relationships among cultivar, geographic area and ripeness stage are discussed.

Carotenoids and chlorophyll derivatives play a key role in Extra Virgin Olive Oils (EVOOs). Many factors, such as cultivar, geographic origin, maturity of olives, climate and storage conditions, influence the pigments' content. The quantification of pigments is usually done by chromatographic techniques. However, recent works evidenced the potentialities of UV-visible-related methodologies. In this research, a selection of EVOO samples produced from olives harvested at the beginning of November 2014 in Greece, Tunisia, Italy and Spain, was investigated in terms of pigments by means of two methods. The first one is a recent approach based on the mathematical treatment of near UV-vis absorption spectra of olive oils to quantify in a fast, cheap and non-destructive way four main pigments, namely β-carotene, lutein, pheophytin A and pheophytin B. The second one is a more standard HPLC-DAD method. From the comparison between the two methods, we can conclude that the new near UV-vis approach gives reliable results, with good precision and high reproducibility. Pigments quantified by these two methods in EVOOs produced in four countries from different cultivars are analyzed by principal component analysis (PCA). Results indicate that pigments can be correlated to several factors such as ripeness stage, geographic origin and cultivars.