This work studied hydrogen stable isotope composition composition ( δ ²H) of specific compounds released by direct analytical pyrolysis of extra virgin olive oils (EVOOs ) without using any chemical and/or physical treatments, derivatization or previous separation steps. A collection of EVOOs from Mediterranean countries was used for authentication of the olive oil samples. The results suggest that the methodology used has a high potential to assess EVOOs geographic origin. The approach represents an innovative, fast, reproducible and reliable authentication technique, the authors conclude.

The analysis of the hydrogen stable isotope composition ( δ ² H) of organic compounds provides information about its geographical origin. In this work, δ ² H composition of specific compounds released by direct analytical pyrolysis (Py-CSIA) of extra virgin olive oils EVOOs was studied avoiding the use of any chemical and/or physical treatments, derivatization or previous separation steps. A collection of EVOOs from Mediterranean countries (Portugal, Spain, France, Tunisia and Turkey) was used for authentication of the olive oil samples. The δ ² H value for 9 pyrolysis compounds present in all EVOOs, ranged between −112 and −267 mUr. These compounds were selected as possible surrogate descriptors linked to the olive oil geographic origin. Principal Component Analysis showed that δ ² H was highly correlated with geographical longitude and annual temperature. Multiple Linear Regression analysis revealed that δ ² H value of pyrolysis compounds can significantly (P < 0.05) predicts longitude, mean annual temperature and distance to the sea. The results suggest that the methodology used has a high potential to assess EVOOs geographic origin. This is the first report that evaluates δ ² H directly from the pyrolysis products of olive oil using Py-CSIA. The approach used represents an innovative, fast, reproducible and reliable authentication technique.

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