**6. References**


The results obtained in this work and discussed in this chapter have shown how important is the method of extraction and the storage of an olive oil (Ben Hassine, et al., 2011; Romano, et al., 2008). A high-quality olive oil can be obtained preferring two phases extraction systems to the classical extraction ones where hydraulic pistons with a pressure of about 400 atm are applied and, storing it in dark glass bottles to better preserve its aroma and phenolic

This work was supported by "Riom II – Risorse aggiuntive" project sponsored by the Italian Ministry of Agricultural, Food and Forest Policies (MIPAF); by a grant from the ''Institute of Olivier of Sfax'' and by the 'Ministère de l'Enseignement Supérieur de la Recherche Scientifique et de la Technologiè (UR03/ES08 Human Nutrition and Metabolic Disorders).

Angerosa, F.; Di Giacinto, L.; Basti, C. & Serraiocco, A. (1996). Influence of environmental

Angerosa, F.; Camera, L.; d'Alessandro, N. & Mellerio, G. (1998a). Characterization of Seven

Angerosa, F.; d'Alessandro, N.; Basti, C. & Vito, R. (1998b). Biogeneration of Volatile

Angerosa, F.; Basti, C. & Vito, R. (1999). Virgin Olive Oil Volatile Compounds from

Aparicio, R. & Morales, M. T. (1998). Characterization of olive ripeness by green aroma compounds of virgin olive oil. *J. Agric. Food Chem*., Vol.46, pp. 1116-1122 Benincasa, C.; De Nino, A.; Lombardo, N.; Perri, E.; Sindona, G. & Tagarelli, A. (2003).

Cerretani, L., Bendini, A., Rotondi, A, Lercker, G. & Toschi, T.G. (2005). Analytical

Christie, WW. (1998). The preparation of derivatives of fatty acids. In: *Gas chromatography* 

*and lipids*. Ayr, Scotland: The Oily Press: 1998, pp. 64–84

parameters on the virgin olive oil composition. *Riv. Ital. Sostanze Grasse*, Vol.73, pp.

New Hydrocarbon Compounds Present in the Aroma of Virgin Olive Oils. *J. Agric.* 

Compounds in Virgin Olive Oil: Their Evolution in Relation to Malaxation Time. *J.* 

Lipoxygenase Pathway and Characterization of Some Italian Cultivars. *J. Agric.* 

Assay of aroma active components of virgin olive oils from southern italian regions by SPME-GC/ion trap mass spectrometry, *J. Agric. Food Chem*. Vol.51, pp. 733-741 Ben Hassine, K., Issaaoui, M., Ben Slama, M., Ayadi, M., Lazzez, A., Benincasa, C., Sindona,

G., Perri, E., Kammoun, N. & Hammami, M. (2011). Effect of extraction systems on the sensory properties of 'Arbequina' introduced in Tunisia and autochthonous virgin olive oils. Proceeding: "15th Simposium Científico-Técnico Expoliva,

comparison of monovarietal virgin olive oils obtained by both a continuous industrial plant and a low-scale mill. *European Journal of Lipid Science and* 

**4. Conclusions** 

compounds.

**6. References** 

461-467

**5. Acknowledgment** 

We thank M. J. Duff for English revision.

*Food Chem.*, Vol.46, pp. 648-653

*Food Chem*., Vol.47, pp. 836-839

EXPOLIVA, May 2007, Jaén (Spain).

*Technology*, Vol.107, pp. 93-100

*Agric. Food Chem*., Vol.46, pp. 2940-2944


**2** 

*Portugal* 

**Olive Oil Composition: Volatile Compounds** 

In general olive oil is defined on the basis of its sensory characteristics. European Union (EU) regulations establish the organoleptic quality of virgin olive oil by means of a panel test, evaluating positive and negative descriptors (EU regulations). For the organoleptic assessment, several volatile compounds are considered as the main responsible for negative and positive attributes. Volatile compounds, either major or minor, are crucial to olive oil quality; even when present below their olfactory threshold, they can still be important to understand their formation and degradation pathways and provide useful quality marker

Volatile composition of olive oils can be influenced by a number of factors, from agronomic and climatic aspects to technological ones. Cultivar, geographic region, ripeness, harvest and processing methods can affect the volatile composition of olive oil. Storage time is also critical for quality. In order to evaluate the volatile profile of olive oil, sensitive analytical techniques as well as extraction procedures were developed. The big issues on aroma analysis are, the loss of compounds during sample preparation steps, and the knowledge that some of the so-called "compounds of interest" (with higher aroma threshold) are, probably, present only in trace amounts. Due to its nature, olive oil is a difficult matrix; for these reasons several methods have been, so far, proposed. The advantages and drawbacks of these methods will be further discussed. One dimension-Gas Chromatography (1D-GC) analysis was, until recently, the most used method to analyze volatiles in different matrices. The increased development of 2D-GC, allowing higher sensitivity and enhanced separation power, is changing the 1D-GC approach. The type of 2D and/or 3D qualitative and quantitative information, provided by 2D-GC systems, promoted the development of powerful chemometrics tools allowing a useful, and potentially easy, way for data interpretation. Fingerprint comparison can be used on a routine basis, providing important and quick information concerning differences among the olive oils produced and, probably

**1. Introduction** 

information.

most important, also allowing frauds detection.

Marco D.R. Gomes da Silva1, Ana M. Costa Freitas2,

*1REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia/ Universidade Nova de Lisboa, Campus da Caparica, 2Escola de Ciências e Tecnologia, Departamento de Fitotecnia,* 

*Instituto de Ciências Agrárias e Ambientais Mediterrânicas ICAAM,* 

Maria J. B. Cabrita2 and Raquel Garcia2

*Universidade de Évora, Évora,* 

