Filtered vs. naturally sedimented and decanted virgin olive oil during storage: Effect on quality and composition

The aim of this study was to compare quality changes and compositional characteristics (fatty acids, total phenols, sensory profile) during 12 months storage of Buža and Istarska bjelica cv. virgin olive oils clarified by filtration at an industrial scale (filter press equipped with cellulose filters) and those clarified by natural sedimentation and decantation, as well as the influence of filtration of virgin olive oils on sterols and triterpene dialcohols composition. There were no significant differences in hydrolytic deterioration and sensory scores during the whole storage period between filtered and naturally sedimented oil samples. After 6 months, natural sedimentation was more favorable as regards delaying of oxidative deterioration, while filtration provided a more stable sensory profile. As regards total phenols the impact of the clarifying procedure was dependent on cultivar and fruit ripeness degree and it was more emphasized than the impact of storage. Filtration slightly affected the fatty acids composition, but natural sedimentation and decantation had no effect on it. Nevertheless, filtration did not compromise the confirmation of virgin olive oil authenticity according to the fatty acid composition, as well as according to sterols and triterpene dialcohols.