Chemical compositional peculiarities and functional properties of monovarietal extra virgin olive oils from Marche Region

Extra virgin olive oil (EVOO) has several interesting nutritional, healthy and sensory properties. However, great differences in terms of chemical composition can be found among different EVOO, depending on several factors, like the olive cultivar, agronomical, geographical, climatic and technological factors, olive physiological state, ripening degree and others [1]. Monovarietal EVOOs (MEVOO) are niche products, highly appreciated for their specific characteristics, many of which are strictly related to the variety. In Marche region about 20 cultivars (cv) are grown [2] and in the present study, MEVOOs from 5 of these cv representing some of the most spread on Marche region territory and producing appreciated oils that are still not investigated in detail, have been selected (Piantone di Mogliano, Ascolana tenera, Raggia, Mignola, Coroncina), with the final aim of providing a fingerprint of these oils, highlighting peculiar features in order to identify strength or weakness points thus contributing to their valorization. Their chemical characteristics have been also compared with those of blends commonly found on the large scale retail distribution market, thus also contributing to create more awareness on the compositional differences finally leading to the different quality of olive oil. Samples were provided by directly by producers in two subsequent years and several parameters that contribute from several points of view to the overall olive oil quality have been investigated, like e.g. fatty acid composition, hydrophilic phenolic substances, α-tocopherol, squalene content, volatile substances composition, antioxidant activity; also sensorial analysis has been performed by an official panel. The results obtained clearly highlight some key strength of the cv investigated, where for example in each of the two years, Piantone di Mogliano MEVOOs have the highest average oleic acid percentage, Mignola the highest average concentration of α-tocopherol and Ascolana tenera has the highest average squalene concentration. Also functional properties, i.e. prebiotic activity, has been investigated, comparing the effect of MEVOOs to that of inulin in a semi-continuous fermentation system inoculated with a pool of human faeces under anaerobic conditions, to mime a colonic human fermentation. Results will be presented and discussed. References [1] Fiorini D, Boarelli MC, Conti P, Alfei B, Caprioli G, Ricciutelli M, Sagratini G, Fedeli D, Gabbianelli R, Pacetti D. Chemical and sensory differences between high price and low price extra virgin olive oils. Food Res Int. 2018;105:65-75. [2] Pannelli G, Alfei B, Santinelli A., 1998. “Varietà di olivo nelle Marche” - A.S.S.A.M., Ancona. Acknowledgements: supported by grant FAR 2014/2015 (University of Camerino).