Fatty acid composition and climate change: a long-term analysis in Italian Extra Virgin Olive Oils

Italian olive growing is undergoing significant changes due to climate change, with potential implications for extra virgin olive oil (EVOO) quality. This study analyzes long-term variations in the fatty acid composition of Italian monovarietal oils by linking chemical data with climatic conditions of the production seasons. A database of 1564 oil samples collected between 1983 and 2023 was compiled from scientific publications and institutional archives. Samples were modelled against Growing Degree Days (GDD), the selected climate proxy, and year, accounting for cultivar and geographic origin. Results indicate emerging trends in fatty acid composition, including a reduction in oleic acid in some cultivars and a relative increase in palmitic and linoleic acids, potentially linked to rising temperatures. However, these changes are small: fatty acid proportions remain within narrow ranges and within International Olive Council (IOC) limits, indicating that although statistically significant, they are not practically relevant to EVOO quality or oxidative stability. Cultivars previously identified as more sensitive to climate variability showed distinct response patterns, with different compensatory mechanisms linked to the decline in oleic acid. This study provides a robust dataset for future research into the climate-EVOO quality relationship, deepening understanding of environmental influences on the olive oil supply chain.