Trade-Offs Between Fruit Health, Oil Accumulation, and Bioactive Retention During Olive Fruit Ripening in Four Spanish Olive Cultivars

This study evaluated the influence of ripening stage on sanitary status, fruit characteristics, oil content, and quality parameters in four Spanish olive cultivars (‘Arbequina’, ‘Manzanilla Carrasqueña’, ‘Morisca’, and ‘Picual’) grown in Badajoz, Spain. The sanitary status of olives declined significantly as ripening progressed across all cultivars, with ‘Morisca’ showing the most pronounced deterioration (from 99.33% to 51.11% healthy fruits) and ‘Arbequina’ exhibiting the greatest tolerance (80.17% at full maturity). Oil content on a dry basis increased steadily during ripening in all cultivars, ranging from 35.10 to 36.84% at early stages to 44.26–49.51% at full maturity, while extractability patterns varied among cultivars. Total phenolic compounds decreased significantly in ‘Arbequina’ and ‘Manzanilla Carrasqueña’, while ‘Morisca’ and ‘Picual’ remained stable during ripening. Oxidative stability was highest in ‘Manzanilla Carrasqueña’ (90.28–137.64 h) and ‘Picual’ (100.67–109.37 h) oils, while ‘Arbequina’ and ‘Morisca’ exhibited moderate values (40.04–54.85 h). All oils showed acidity levels below the 0.80% limit for extra virgin classification throughout ripening (0.09–0.21% oleic acid). These findings provide valuable insights for optimizing harvest timing according to desired quality profiles, with early harvest recommended for maximizing phenolic content and oxidative stability in ‘Arbequina’ and ‘Manzanilla Carrasqueña’, while ‘Morisca’ and ‘Picual’ offer greater flexibility in harvest scheduling without compromising oil quality.