Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.8
5.2
Journals
Foods
Special Issues
Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment...
share announcement

Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization

A special issue of Foods (ISSN 2304-8158). This special issue belongs to the section "Food Security and Sustainability".

Deadline for manuscript submissions: closed (30 July 2021) | Viewed by 31292

Special Issue Editors

Prof. Dr. Cosima Damiana Calvano

E-Mail Website
Guest Editor
Università degli Studi di Bari, Dipartimento di Farmacia-Scienze del Farmaco, Centro Interdipartimentale SMART, Bari, Italy
Interests: MALDI mass spectrometry; liquid chromatography; novel food; food lipidomics; proteomics; food safety; oil aduleration
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Antonia Tamborrino

E-Mail Website
Guest Editor
Department of Agricultural and Environmental Science, University of Bari Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy
Interests: deals with the innovation and optimization of agro-food industry equipment and plants, design of the food pilot plants and their implementation in the industrial environmental; sensors and real time process control; processes settings; influence of the machine design parameters on food quality; other scientific targets are the waste management; composting systems, harvesting mechanization system and harvesting machine
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Olive by-products have long been considered as a problematic waste material, but this view has recently changed, leading to the recognition of by-products such as leaves, aqueous olive mill wastewater, olive cake, and olive pomace as potential low-cost sources of phenols and antioxidants that can be extracted and used as natural additives in the food and drug industries. The polyphenols present in the olive leaves have been shown to possess important antioxidant, anti-inflammatory, anti-atherogenic, and antimicrobial activities, and even possible anti-cancer effects. The chemical composition of olive by-products can be quite dissimilar from that of olive fruit; for instance, olives are very rich in secoiridoid glucosides, while olive mill wastewater contains a high concentration of secoiridoid derivatives. On one hand, due to the presence of an outstanding number of phenols, flavonoids, and secoiridoids—most of them not fully characterized—there is a need to develop rapid, sensitive, and accurate analytical platforms for their characterization.

On the other hand, the application of green techniques to the extraction of bioactive compounds from olive leaves or other by-products could be of great interest, not only for the attainment of these natural active compounds, but also for the possibility of re-using significant by-products from the industry. For example, a few recent reports have studied the influence of the different extraction conditions on the achievement of phenolic antioxidants from these substances.

This Special Issue focuses both on the recent advancements in technologies for the extraction of target compounds from olive by-products and on their characterization by advanced ESI–MS, ESI–MS/MS, and MALDI-MS techniques with the aim of valorizing these compounds. We also welcome studies directed towards the relationship between extraction conditions and resultant bioactive fingerprints, even considering the latest innovations introduced in the olive oil extraction plant and their influence on the by-product characteristics. 

Prof. Cosima damiana Calvano
Dr. Antonia Tamborrino
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Foods is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • innovative extraction techniques
  • olive leaves
  • olive by-products
  • LC–MS/MS
  • MALDI-MS
  • antioxidants
  • polyphenols
  • olive oil extraction process

Published Papers (10 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

6 pages, 205 KiB  
Editorial
Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization
by Cosima D. Calvano and Antonia Tamborrino
Foods 2022, 11(6), 768; https://doi.org/10.3390/foods11060768 - 08 Mar 2022
Cited by 13 | Viewed by 2051
Abstract
Presently, olive oil production signifies a valuable economic income for Mediterranean countries, where approximately 98% of the world’s production is established [...] Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)

Research

Jump to: Editorial, Review

17 pages, 2961 KiB  
Article
Composting of Olive Mill Pomace, Agro-Industrial Sewage Sludge and Other Residues: Process Monitoring and Agronomic Use of the Resulting Composts
by Alessandro Leone, Roberto Romaniello, Antonia Tamborrino, Luciano Beneduce, Anna Gagliardi, Marcella Giuliani and Giuseppe Gatta
Foods 2021, 10(9), 2143; https://doi.org/10.3390/foods10092143 - 10 Sep 2021
Cited by 6 | Viewed by 2242
Abstract
The viability of co-composting of olive mill pomace added to sewage sludge with other organic residues was evaluated and the agronomic use of the final composts was investigated. Two composting piles at different carbon-nitrogen ratios were performed, in which olive mill pomace (OMP), [...] Read more.
The viability of co-composting of olive mill pomace added to sewage sludge with other organic residues was evaluated and the agronomic use of the final composts was investigated. Two composting piles at different carbon-nitrogen ratios were performed, in which olive mill pomace (OMP), sewage sludge from vegetable processing (SS), fresh residues from artichoke processing residues (AR), and wheat straw (WS) were used. The two composting piles were placed inside a specially built greenhouse and a turning machine pulled by a tractor was used for turning and shredding the organic matrix (every 6 days) during the process. The humidity and temperature of organic matrices have been monitored and controlled during the entire composting process, which lasted 90 days. The process was also monitored to evaluate the microbiological safety of the final compost. The humidity of both piles was always kept just above 50% until the end of the thermophilic phase and the maximum temperature was about 50 °C during the thermophilic phase. The carbon-nitrogen ratio decreased from 21.4 and 28.2, respectively (initial value at day 1 in Pile A and B), to values ranging from 12.9 to 15.1, both composts that originated from the two different piles were microbiologically safe. During a two-year period, the effects of different types of compost on the main qualitative parameters of processing tomato and durum wheat was evaluated. Five fertilization treatments were evaluated for tomato and durum wheat crops: unfertilized control (TR1); compost A (TR2); compost B (TR3); ½ mineral and ½ compost A (TR4); and mineral fertilizer commonly used for the two crops (TR5). Concerning the processing tomato yield, TR5 and TR4 showed the best results (2.73 and 2.51 kg, respectively). The same trend was observed considering the marketable yield per plant. The only difference was related to the treatments that included the compost (2.32, 1.77, and 1.73 kg/plant for TR4, TR3, and TR2, respectively). As regards the qualitative parameters of tomato, the highest average weight of the fruits was found in the TR5, TR4, and TR3 treatments (respectively, 73.67 g, 70.34 g, and 68.10 g). For durum wheat, only the protein component was differentiated between treatments. Furthermore, wheat grain yield parameters generally increased by combined application of mineral fertilizer and compost. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

16 pages, 1228 KiB  
Article
Quality Evaluation of Shrimp (Parapenaeus longirostris) Treated with Phenolic Extract from Olive Vegetation Water during Shelf-Life, before and after Cooking
by Dino Miraglia, Marta Castrica, Sonia Esposto, Rossana Roila, Roberto Selvaggini, Stefania Urbani, Agnese Taticchi, Beatrice Sordini, Gianluca Veneziani and Maurizio Servili
Foods 2021, 10(9), 2116; https://doi.org/10.3390/foods10092116 - 07 Sep 2021
Cited by 7 | Viewed by 2207
Abstract
The focus of this study was to assess the quality traits and sensory profile of cooked rose shrimps (Parapenaeus longirostris) treated with a phenolic extract, derived from olive vegetation water (PEOVW). To achieve the aim, four different groups of shrimps were [...] Read more.
The focus of this study was to assess the quality traits and sensory profile of cooked rose shrimps (Parapenaeus longirostris) treated with a phenolic extract, derived from olive vegetation water (PEOVW). To achieve the aim, four different groups of shrimps were analysed, specifically the control (CTRL) group, where the shrimps were soaked in tap water; sulphites (S) group with shrimps soaked in 0.5% sodium metabisulfite tap water solution, phenolic extract (PE) group where a tap water solution containing 2 g/L of phenols was used; and PE+S group where the shrimps were dipped in 0.25% sodium metabisulfite tap water solution containing 1 g/L of phenols. The groups were then stored at 2 °C and analysed on the day of packaging (D0), after 3 (D3), 6 (D6), and 8 (D8) days. On each group, microbiological parameters such as Enterobacteriaceae, mesophilic and psychrotrophic bacteria, and colorimetric indices were investigated on six (n = 6) shrimps before cooking, while the evolution of the phenolic content, antioxidant activity, and sensory analysis during the storage period were evaluated on cooked shrimps. Regarding colour coordinates, there were no noteworthy variations overtime nor between groups, while it is important to note that the microbiological results for the PE group showed at each time interval and for all the considered parameters, significantly lower values than the other groups (p < 0.05). This result is very interesting when considered further in correlation with the sensory analysis, where shrimps mainly in PE and secondarily in PE+S groups were shown to retain the freshness characteristics better than the other groups (α = 0.01), without giving the shrimps any particularly bitter and pungent sensations typical of the olive phenolic compounds. In conclusion, the results obtained in this study give PEOVW the potential to be valorised in the food sector and, above all, it could represent a sustainable solution to reduce the use of synthetic additives. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

18 pages, 2378 KiB  
Article
A Real Case Study of a Full-Scale Anaerobic Digestion Plant Powered by Olive By-Products
by Antonia Tamborrino, Filippo Catalano, Alessandro Leone and Biagio Bianchi
Foods 2021, 10(8), 1946; https://doi.org/10.3390/foods10081946 - 21 Aug 2021
Cited by 10 | Viewed by 2657
Abstract
The anaerobic digestion plant studied in this paper is one of the first full-scale plants using olive oil by-products. This is a two-stage plant with a power of 100 kWe. Two tests were performed: the first on olive pulp and pitted pomace and [...] Read more.
The anaerobic digestion plant studied in this paper is one of the first full-scale plants using olive oil by-products. This is a two-stage plant with a power of 100 kWe. Two tests were performed: the first on olive pulp and pitted pomace and the second on biomass consisting of 10% crushed cereal. In both cycles, the retention time was 40 days. The production of biogas was between 51 and 52 m3/h, with limited fluctuations. The specific production values of biogas indicate that a volume of biogas greater than 1 m3/kg was produced in both tests. The produced biogas had a methane percentage of about 60% and the specific production (over total volatile solids, TVS) of methane was of the order of 0.70 m3methane/kgTVS. FOS/Alk (ratio between volatile organic acids and alkalinity) was always lower than 1 and tended to decrease in the second digester, indicating a stable methanogenic phase and the proper working of the methanogenic bacteria in the second reactor. The concentration of incoming biomass TPC (total polyphenols content) can vary significantly, due to the seasonality of production or inadequate storage conditions, but all measured values of TPC, between 1840 and 3040 mg gallic acid kg−1, are considered toxic both for acidogenic and methanogenic bacteria. By contrast, during the process the polyphenols decreased to the minimum value at the end of the acidogenic phase, biogas production did not stop, and the methane percentage was high. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

18 pages, 2088 KiB  
Article
Encapsulation of Olive Pomace Extract in Rocket Seed Gum and Chia Seed Gum Nanoparticles: Characterization, Antioxidant Activity and Oxidative Stability
by Alican Akcicek, Fatih Bozkurt, Cansu Akgül and Salih Karasu
Foods 2021, 10(8), 1735; https://doi.org/10.3390/foods10081735 - 27 Jul 2021
Cited by 21 | Viewed by 3021
Abstract
The aim of this study was to determine the potential use of rocket seed and chia seed gum as wall materials, to encapsulate and to prevent degradation of olive pomace extract (OPE) in polymeric nanoparticles, and to characterize olive pomace extract-loaded rocket seed [...] Read more.
The aim of this study was to determine the potential use of rocket seed and chia seed gum as wall materials, to encapsulate and to prevent degradation of olive pomace extract (OPE) in polymeric nanoparticles, and to characterize olive pomace extract-loaded rocket seed gum nanoparticles (RSGNPs) and chia seed gum nanoparticles (CSGNPs). The phenolic profile of olive pomace extract and physicochemical properties of olive pomace, rocket seed gum (RSG), and chia seed gum (CSG) were determined. The characterization of the nanoparticles was performed using particle size and zeta potential measurement, differential scanning calorimeter (DSC), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), encapsulation efficiency (EE%), in vitro release, and antioxidant activity analyses. Nanoparticles were used to form oil in water Pickering emulsions and were evaluated by oxitest. The RSGNPs and CSGNPs showed spherical shape in irregular form, had an average size 318 ± 3.11 nm and 490 ± 8.67 nm, and zeta potential values of −22.6 ± 1.23 and −29.9 ± 2.57, 25 respectively. The encapsulation efficiency of the RSGNPs and CSGNPs were found to be 67.01 ± 4.29% and 82.86 ± 4.13%, respectively. The OPE-RSGNP and OPE-CSGNP presented peaks at the 1248 cm−1 and 1350 cm−1 which represented that C-O groups and deformation of OH, respectively, shifted compared to the OPE (1252.53 cm−1 and 1394.69 cm−1). The shift in wave numbers showed interactions of a phenolic compound of OPE within the RSG and CSG, respectively. In vitro release study showed that the encapsulation of OPE in RSGNPs and CSGNPs led to a delay of the OPE released in physiological pH. The total phenolic content and antioxidant capacity of RSGNPs and CSGNPs increased when the OPE-loaded RSGNPs and CSGNPs were formed. The encapsulation of OPE in RSGNPs and CSGNPs and the IP values of the oil in water Pickering emulsions containing OPE-RSGNPs and OPE-CSGNPs were higher than OPE, proving that OPE-loaded RSGNPs and CSGNPs significantly increased oxidative stability of Pickering emulsions. These results suggest that the RSG and CSG could have the potential to be utilized as wall materials for nanoencapsulation and prevent degradation of cold-pressed olive pomace phenolic extract. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

12 pages, 1510 KiB  
Article
Preliminary Investigation of Different Drying Systems to Preserve Hydroxytyrosol and Its Derivatives in Olive Oil Filter Cake Pressurized Liquid Extracts
by Lucía López-Salas, Inés Cea, Isabel Borrás-Linares, Tatiana Emanuelli, Paz Robert, Antonio Segura-Carretero and Jesús Lozano-Sánchez
Foods 2021, 10(6), 1407; https://doi.org/10.3390/foods10061407 - 18 Jun 2021
Cited by 3 | Viewed by 2560
Abstract
Phenolic compounds present in extra virgin olive oil (EVOO) could be retained in its byproducts during processing. Among them, hydroxytyrosol and its derivatives deserve special attention due to their health benefits recognized by The European Food Safety Authority (EFSA). In the present research, [...] Read more.
Phenolic compounds present in extra virgin olive oil (EVOO) could be retained in its byproducts during processing. Among them, hydroxytyrosol and its derivatives deserve special attention due to their health benefits recognized by The European Food Safety Authority (EFSA). In the present research, the presence of these compounds in the filter cake byproduct was studied by combining pressurized liquid extraction (PLE) and high-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-TOF-MS). The applied optimum extraction parameters were 1500 psi, 120 °C and aqueous ethanol (50:50, v/v). The influence of different drying methods (vacuum-, freeze- and spray-drying) in the recovery of phenolic compounds was also evaluated. A total of 16 compounds from EVOO were identified in the extracts, 3 of them being hydroxytyrosol-related compounds, 6 substances of oleoside and elenolic acid derivatives, together with 6 secoiridoids and 1 lignan. The results highlighted the great number of phenolic compounds recovered from filter cake with these techniques, being even higher than the reported content in EVOO and other byproducts. The combination of PLE and freeze-drying resulted in being the best procedure for the recovery of phenolic compounds from filter cake byproduct. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Graphical abstract

16 pages, 1032 KiB  
Article
Analytical Characterization of Water-Soluble Constituents in Olive-Derived By-Products
by Pablo Doménech, Aleta Duque, Isabel Higueras, José Luis Fernández and Paloma Manzanares
Foods 2021, 10(6), 1299; https://doi.org/10.3390/foods10061299 - 05 Jun 2021
Cited by 12 | Viewed by 2595
Abstract
Olive trees constitute one of the largest agroindustries in the Mediterranean area, and their cultivation generates a diverse pool of biomass by-products such as olive tree pruning (OTP), olive leaves (OL), olive stone (OS), and extracted olive pomace (EOP). These lignocellulosic materials have [...] Read more.
Olive trees constitute one of the largest agroindustries in the Mediterranean area, and their cultivation generates a diverse pool of biomass by-products such as olive tree pruning (OTP), olive leaves (OL), olive stone (OS), and extracted olive pomace (EOP). These lignocellulosic materials have varying compositions and potential utilization strategies within a biorefinery context. The aim of this work was to carry out an integral analysis of the aqueous extractives fraction of these biomasses. Several analytical methods were applied in order to fully characterize this fraction to varying extents: a mass closure of >80% was reached for EOP, >76% for OTP, >65% for OS, and >52% for OL. Among the compounds detected, xylooligosaccharides, mannitol, 3,4-dihydroxyphenylglycol, and hydroxytyrosol were noted as potential enhancers of the valorization of said by-products. The extraction of these compounds is expected to be more favorable for OTP, OL, and EOP, given their high extractives content, and is compatible with other utilization strategies such as the bioconversion of the lignocellulosic fraction into biofuels and bioproducts. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

15 pages, 2598 KiB  
Article
Effect of an Olive Vegetation Water Phenolic Extract on the Physico-Chemical, Microbiological and Sensory Traits of Shrimp (Parapenaeus longirostris) during the Shelf-Life
by Dino Miraglia, Marta Castrica, Laura Menchetti, Sonia Esposto, Raffaella Branciari, David Ranucci, Stefania Urbani, Beatrice Sordini, Gianluca Veneziani and Maurizio Servili
Foods 2020, 9(11), 1647; https://doi.org/10.3390/foods9111647 - 11 Nov 2020
Cited by 19 | Viewed by 2639
Abstract
The aim of this study was to evaluate the effects of phenolic extract derived from olive vegetation water (PEOVW) in deep-water rose shrimps (Parapenaeus longirostris) at the day of packaging (D0) and after three (D3), six (D6) and eight (D8) days [...] Read more.
The aim of this study was to evaluate the effects of phenolic extract derived from olive vegetation water (PEOVW) in deep-water rose shrimps (Parapenaeus longirostris) at the day of packaging (D0) and after three (D3), six (D6) and eight (D8) days of refrigerated storage. Freshly caught shrimps were randomly divided into four groups: the phenolic extract (PE) group (2 g/L of phenols); the sulfites (S) group (0.5% sodium metabisulfite solution); the phenolic extract + sulfites (PE + S) group (0.25% sodium metabisulfite solution with 1 g/L of phenols), and the control (CTRL) group (tap water). Concerning color coordinates, there were no variations either between groups or over time, while it is important to highlight that phenolic extract (PE group) led to a significant reduction in total volatile basic nitrogen (TVB-N; p < 0.001) and thiobarbituric reactive substances (TBARS; p < 0.001) values. Furthermore, PE also had a relevant effect in reducing bacterial counts and decreasing the microbial development. Finally, as concerns melanosis, the effect of phenolic extract alone was marginal, but when combined with half a dose of sodium metabisulfite, it was as effective as the shrimps treated with only sodium metabisulfite in delaying black spots (p < 0.05). These results are very promising with a view to commercializing additive-free shrimps. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

12 pages, 1800 KiB  
Article
Characterization and Bio-Accessibility Evaluation of Olive Leaf Extract-Enriched “Taralli”
by Annamaria Cedola, Carmen Palermo, Diego Centonze, Matteo Alessandro Del Nobile and Amalia Conte
Foods 2020, 9(9), 1268; https://doi.org/10.3390/foods9091268 - 10 Sep 2020
Cited by 24 | Viewed by 2776
Abstract
Olive leaves are rich in many compounds precious for human health. Due to this property, the current study was aimed to valorize the extract from this by-product in a cereal-based food, very popular all around the world, the “taralli”. To this aim, ultrasound-assisted [...] Read more.
Olive leaves are rich in many compounds precious for human health. Due to this property, the current study was aimed to valorize the extract from this by-product in a cereal-based food, very popular all around the world, the “taralli”. To this aim, ultrasound-assisted extraction was applied to dried olive leaves to obtain the extract, used as “taralli” ingredient, instead of white wine. The “taralli” with and without extract was subjected to in vitro digestion to assess the quantity of polyphenolic compounds released in the gastrointestinal tract to become available for absorption. Total content of phenols and flavonoids, as well as the antioxidant capacity, was measured on both cooked and uncooked samples, before and after digestion. In addition, High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) of the three most abundant polyphenols present in olive leaf extracts, such as oleuropein, hydroxytyrosol, and verbascoside, was carried out at the three stages of the digestion process. The results showed that the substitution of white wine with olive leaf extract increased the total content of polyphenols and flavonoids and the antioxidant capacity. Bio-accessibility of the main phenolic compounds demonstrated that oleuropein resisted slightly after gastric digestion but was almost completely degraded in the intestinal phase, while hydroxytyrosol and verbascoside were not resistant to the digestion process from the gastric phase. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Graphical abstract

Review

Jump to: Editorial, Research

28 pages, 986 KiB  
Review
Bioactive Compounds in Waste By-Products from Olive Oil Production: Applications and Structural Characterization by Mass Spectrometry Techniques
by Ramona Abbattista, Giovanni Ventura, Cosima Damiana Calvano, Tommaso R. I. Cataldi and Ilario Losito
Foods 2021, 10(6), 1236; https://doi.org/10.3390/foods10061236 - 29 May 2021
Cited by 43 | Viewed by 6644
Abstract
In recent years, a remarkable increase in olive oil consumption has occurred worldwide, favoured by its organoleptic properties and the growing awareness of its health benefits. Currently, olive oil production represents an important economic income for Mediterranean countries, where roughly 98% of the [...] Read more.
In recent years, a remarkable increase in olive oil consumption has occurred worldwide, favoured by its organoleptic properties and the growing awareness of its health benefits. Currently, olive oil production represents an important economic income for Mediterranean countries, where roughly 98% of the world production is located. Both the cultivation of olive trees and the production of industrial and table olive oil generate huge amounts of solid wastes and dark liquid effluents, including olive leaves and pomace and olive oil mill wastewaters. Besides representing an economic problem for producers, these by-products also pose serious environmental concerns, thus their partial reuse, like that of all agronomical production residues, represents a goal to pursue. This aspect is particularly important since the cited by-products are rich in bioactive compounds, which, once extracted, may represent ingredients with remarkable added value for food, cosmetic and nutraceutical industries. Indeed, they contain considerable amounts of valuable organic acids, carbohydrates, proteins, fibers, and above all, phenolic compounds, that are variably distributed among the different wastes, depending on the employed production process of olive oils and table olives and agronomical practices. Yet, extraction and recovery of bioactive components from selected by-products constitute a critical issue for their rational valorization and detailed identification and quantification are mandatory. The most used analytical methods adopted to identify and quantify bioactive compounds in olive oil by-products are based on the coupling between gas- (GC) or liquid chromatography (LC) and mass spectrometry (MS), with MS being the most useful and successful detection tool for providing structural information. Without derivatization, LC-MS with electrospray (ESI) or atmospheric pressure chemical (APCI) ionization sources has become one of the most relevant and versatile instrumental platforms for identifying phenolic bioactive compounds. In this review, the major LC-MS accomplishments reported in the literature over the last two decades to investigate olive oil processing by-products, specifically olive leaves and pomace and olive oil mill wastewaters, are described, focusing on phenolics and related compounds. Full article
(This article belongs to the Special Issue Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-10
Back to TopTop