Abstract
Olive oil production represents an agro-industrial activity of vital economic importance for many Mediterranean countries. However, it is associated with the generation of a huge amount of by-products, both in solid and liquid forms, mainly constituted by olive mill wastewater, olive pomace, wood, leaves, and stones. Although for many years olive by-products have only been considered as a relevant environmental issue, in the last decades, numerous studies have deeply described their antioxidant, anti-inflammatory, immunomodulatory, analgesic, antimicrobial, antihypertensive, anticancer, anti-hyperglycemic activities. Therefore, the increasing interest in natural bioactive compounds represents a new challenge for olive mills. Studies have focused on optimizing methods to extract phenols from olive oil by-products for pharmaceutical or cosmetic applications and attempts have been made to describe microorganisms and metabolic activity involved in the treatment of such complex and variable by-products. However, few studies have investigated olive oil by-products in order to produce added-value ingredients and/or preservatives for food industries. This review provides an overview of the prospective of liquid olive oil by-products as a source of high nutritional value compounds to produce new functional additives or ingredients and to explore potential and future research opportunities.
Highlights
Olive growing is spread over 10 million and 800 thousand hectares across the world, 97% of which are concentrated in the Mediterranean area, where the olive tree (Olea europaea L.) has always occupied a central role in among its population
Studies have focused on optimizing methods to extract phenols from olive oil by-products for pharmaceutical or cosmetic applications and attempts have been made to describe microorganisms and metabolic activity involved in the treatment of such complex and variable by-products
A pool of Candida boidinii and Pichia holstii strains has been selected for its ability to reduce the phenolic content of olive mill wastewaters (OMWW) combined with 6.0 g/L of (NH4)2SO4 at 10 ◦C [65]
Summary
Olive growing is spread over 10 million and 800 thousand hectares across the world, 97% of which are concentrated in the Mediterranean area, where the olive tree (Olea europaea L.) has always occupied a central role in among its population. The two-phase system, adopted in Spain and widespread in most countries, does not require the addition of water, other than during horizontal centrifugation, and results in olive oil and semi-solid olive cake [2]. The three-phase decanter process requires the addition of hot water, in 0.6–1.3 m3/1000 kg of processed olives [2] and results in olive oil, OMWW, and olive cake (residual solids). As a result of these differences, the three-phase extraction process presents a slightly higher yield, leading to a lower amount of olive cake but a significantly higher production of OMWW. In addition to traditional decantation, various systems of purification and disposal have been proposed, such as chemical, agronomic, and biotechnological interventions Such approaches underestimate “waste” as a possible primary resource of high nutritional value compounds.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
