Tipicità e territorialità dell'olio extra vergine di oliva piemontese: una analisi comparativa con oli ottenuti da olivi centenari presenti nella regione Piemonte

Olive oil has been closely linked to the Mediterranean area for centuries, thanks to its ideal climatic, cultural, and territorial conditions for production. Climate change is threatening this ancient tradition and causing an important decline in olive production, especially in the south. Olive trees are now being successfully cultivated in northern regions such as Piedmont. Rigorous research into varieties suitable for the new conditions has been conducted. The global demand for high-quality olive oil is increasing, which presents a significant opportunity for small-scale producers such as those in Piedmontese oil to expand their market share. The typicality of Piedmontese olive oil has not been defined yet. However, regional bodies and institutions are actively carrying on characterization and promotion activities to identify and enhance the distinctive characteristics of the product. This thesis aims to identify those typical elements of Piedmontese virgin olive oils. The study analyzed commercial samples of extra virgin olive oil (EVO) provided by local companies and oils obtained from centennial native olive trees (EVOS) identified in different areas of the Piedmont region. The parameters examined included peroxide value, total free acidity, fatty acid composition, total sterol content, phenolic substance content, and composition of volatile organic substances. All oils, except for one sample, displayed peroxide and acidity values within the established limits. The composition of fatty acids was similar in both EVO and EVOS samples. However, EVO oils had a higher n-6/n-3 ratio compared to EVOS oils. These findings demonstrate the superiority of EVOS oils in terms of their nutritional value and health benefits. Additionally, EVO samples had a significantly higher concentration of cycloartenol than EVOS samples. The monocultivar Bianchera and Grignan oils showed the highest phenol content reaching 350 mg/kg oil. Additionally, the EVOS sample obtained from a plant located in the municipality of Gravere had the highest concentration of phenolic substances. The analysis of volatile organic compounds unequivocally demonstrated the presence of over 70 distinct substances, with both groups being predominantly characterized by the presence of aldehydes. Therefore, despite the study's focus on a single harvesting campaign (2022-2023) and a limited number of samples, it has provided important information. The high oleic acid content and significant presence of volatile compounds, such as geraniol and 2-hexenal, demonstrated that extra virgin olive oil produced in Piedmont is of comparable quality to other Italian varieties. These findings provide a strong basis for evaluating the feasibility of implementing production regulations that ensure the traceability and authenticity of the oil.