Studio dell'influenza genotipo-ambiente sulle caratteristiche qualitative dell'olio vergine di oliva (Olea europea L.)

The quality of virgin olive oil depends on cultivar, environment, orchard management, oil extraction and storage technology. The aim of this PhD project was to investigate the cultivar and environmental influences on virgin olive oil quality during 4 years (1998-2001). The first goal (cultivar influence) was divided in three aspects: chemiometric (61 oils from 18 cultivars), enzymatic (22 olive samples from 3 cultivars at different ripening stages) and aromatic (40 commercial oils). The second goal (environmental influence) was divided in two parts: mesoclimate effect (77 oils of 4 cultivars from 17 orchards in western cost of lake Garda, northern Italy) and macroclimate effect (33 oils of 3 cultivars at three ripening stages from different Italian regions). The analytical determinations on oils were: fatty acids, triglycerides, aliphatic and triterpenic alcohols, sterols, polyphenols, tocopherols, pigments, volatile compounds, oxidative stability and sensory analysis. The cultivar resulted the most important factor influencing the oil quality, while the environment was less important in influencing the oil orchard origin in Garda area, whereas it was more significant in separating the cultivar and the origin from different region. Some cultivars were similar according to chemical profile, whereas others resulted well distinct and characterized. In addition, the oxidative stability was correlated to total polyphenols, saturated on polyunsaturated fatty acids ratio and total tocopherols