Effect of Clarification System on the Conservation of Virgin Olive Oil during Its Storage

Abstract

AbstractThe results obtained in this work explain how clarification systems can affect the conservation of virgin olive oils (VOOs) during the storage step. The evolution of the quality and sensory properties during the storage of VOOs clarified by different systems, vertical centrifugal separator (VCS) with minimal water addition and conical bottom settling tank (CBST), is studied at industrial scale for two different crop years. In general, VCS oils show a slight higher moisture and solid impurities content at the end of the storage step due to a higher emulsion grade (because of the emulsion generated) caused by the rotating movement of this clarification system. For the studied clarification systems, no remarkable differences are observed between the oils during their storage for quality indexes. However, these systems show differences regarding oil sensory properties. The VOOs clarified by VCS are characterized by a higher presence of phenol components, higher positive sensory attributes intensity, and higher lipoxygenase (LOX) aldehydes content during their storage. VOOs from CBST show lower phenol content, a higher “non‐LOX” volatiles content, and the presence of sensory defects during storage.Practical Applications: The results obtained in this work are very important in order to provide specific recommendations and scientific support based on objective data to improve VOO quality. As described in this study, the VCS with a minimal water addition can be a better option to produce VOO of improved quality. This clarification system is an efficient and quick operation that reduces the contact between oil and the remaining water and impurities during the storage step. The minimal water addition used in this clarification system allows obtaining VOOs with higher phenol content and positive sensory notes. This leads to prolong VOO shelf‐life and conservation during the storage stage, due to preservation of the quality indexes and minor components with antioxidant activity. Besides, this clarification system reduces the water consumption during oil clarification and generates a lower wastewater volume regarding conventional vertical centrifugation, and therefore can be considered more environmentally friendly.