Olive By-products Research Articles

Synergistic antimicrobial activities of aqueous extract derived from olive byproduct and their modes of action

BackgroundPlant-derived antimicrobials (PDAs) are considered a viable alternative to synthetic antimicrobial agents. Diverse antimicrobial mechanisms of PDAs significantly reduce the risk of developing antimicrobial resistance. Utilization of PDAs also offers economic and environmental advantages, as they can be derived from agricultural byproducts, such as olive pomace.ResultsIn this study, a green, water-based, ultrasound-assisted extraction (UAE) was deployed to obtain aqueous olive pomace extract (OPE) from dry olive pomace. Total phenolic content, extraction yield, chemical compositions, and antimicrobial activities of OPE were evaluated. In addition, the potential synergistic interaction between the phenolic components in OPE and the antimicrobial mechanisms underlying the synergistic interaction were characterized. The results show that ca. 25 mg GAE/g of extraction yields were achieved by the UAE of dry olive pomace. Based on the high-performance liquid chromatography (HPLC) analysis, diverse phenolic compounds such as gallic acid (GA), hydroxytyrosol (HT), and 4-hydroxyphenylacetic acid (4-HPA) were identified in OPE. OPE exhibited strong antimicrobial activities, and 0.2 mg GAE/mL of OPE achieved > 5 log reductions of Escherichia coli O157:H7 and Listeria innocua cells within 30 min of treatment. A 3D isobologram analysis demonstrated that OPE exhibited strong synergistic antimicrobial activities, compared to those of individual phenolic components (GA, HT, or 4-HPA), showing interaction index (γ) of 0.092 and 0.014 against E. coli O157:H7 and L. innocua, respectively (γ < 1: synergistic activity). Antimicrobial mechanism analyses revealed that phenolic components in OPE exerted strong synergistic activities through diverse modes of action, and increased levels of oxidative stress, membrane damage, and decreased levels of metabolic activities were observed in the OPE-treated bacterial cells.ConclusionsThese findings demonstrate an approach for valorizing agricultural byproducts to develop plant byproduct-based antimicrobials with strong synergistic activities. Multiple modes of action of this byproduct extract may enable the control of diverse microbes in food and agriculture systems.Graphical abstract

Polyvinylimidazole-Based Cryogel as an Efficient Tool for the Capture and Release of Oleuropein in Aqueous Media.

A polyvinylimidazole-based cryogel is presented as a pioneering solution for efficient extraction and release of partially water-soluble polyphenols from olive byproducts. Specifically, oleuropein was used as model molecule to evaluate its recovery from water. The material merges the properties of interconnected cryogel structure in adsorbing molecules via fast diffusion flux, with the strong electrostatic interactions acted by imidazole moiety. Such cryogel achieves effective oleuropein binding likely through hydrogen bonding and π-π interactions. Comprehensive assessments of static adsorption kinetics, isotherms, and desorption kinetics underscore the cryogel's efficacy in oleuropein extraction and release, highlighting its pivotal role in valorizing olive wastewater through sustainable biotechnological applications.

Incorporating Olive By-Products in Bísaro Pig Diets: Effect on Dry-Cured Product Quality.

The objective of this study was to assess the impact of incorporating olive cake into the diet of indigenous Bísaro pigs on the quality of processed meat products. To this end, loins and "cachaços" were processed using a standardized manufacturing flowchart to produce dry-cured products. The two products were manufactured using the same formulation, ingredients, and curing process. Concerning the physicochemical composition, there were significant differences between the two products for the parameters of aw (p < 0.001), moisture (p < 0.001), total fat (p < 0.001), protein (p < 0.001), and haem pigments (p < 0.001). The diet significantly impacted the NaCl content (p < 0.05). However, neither the product nor the diet affected the fractions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), or polyunsaturated fatty acids (PUFA) (p > 0.05). However, a significant difference was observed for n-3 (p < 0.05). Adding olive cake increased these fatty acids, and the diet containing 25% centrifuged olive cake showed the highest levels for both products. Compared with the control, the diets containing olive cake had a higher content of n-3 fatty acids, resulting in a lower PUFA n-6/n-3 ratio (p < 0.01).

Anti-oomycete activity of asparagus and olive by-products with potential to control Phytophthora cinnamomi root rot

AbstractThe development of environmentally friendly control methods to mitigate the severe damages caused by Phytophthora cinnamomi in the Mediterranean climate-type ecosystems is essential. In this way, crop waste and by-products which represent between 13 and 65% of agriculture production, are a rich source of bioactive compounds with antifungal and biocide activity. The main objective of this work was to determine the biocide activity against P. cinnamomi of three organic extracts. These extracts enriched in bioactive compounds come from residues of asparagus (Asp) and olive crops (Oliv and OH, from fruits and leaves respectively). They were evaluated at two doses (0.15 and 0.10%) on the mycelial growth and sporangial production of P. cinnamomi by in vitro experiments. Mycelial growth and sporangial production were significant reduced from the three plant extracts at the two doses tested, reaching a total inhibition with Asp at both doses. In general, no phytotoxicity symptoms were observed on seed germination and plant development, except for a plant yield reduction in the substrate treated with Oliv and Asp at the highest dose. In experiments performed in artificially infested soil, Asp induced a reduction of chlamydospores viability greater than 75% compared to unamended soil. Additionally, in planta experiments showed a significant reduction in plant mortality in substrate amended with OH. These results suggest that soil application of Asp and OH can limit P. cinnamomi infectivity and survival, setting the first steps to develop a sustainable method to control the root disease based on agricultural waste circular economy.

Metabolome classification of olive by-products from different oil presses providing insights into its potential health benefits and valorization as analyzed via multiplex MS-based techniques coupled to chemometrics.

The Olive (Olea europaea L.) is one of the most popular edible oil-producing fruits, consumed worldwide for its myriad nutritional and health benefits. Olive oil production generates huge quantities of by-products from the fruit, which are considered environmental hazards. Recently, more and more efforts have been made to valorize olive by-products as a source of low-cost, value-added food applications. The main objective of this study was to globally assess the metabolome of olive fruit by-products, including olive mill wastewater, olive pomace, and olive seeds from fruits from two areas, Siwa and Anshas, Egypt. Gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography with mass spectrometry (UPLC-MS) were used for profiling primary and secondary metabolites in olive by-products. Also, multivariate data analyses were used to assess variations between olive by-product samples. A total of 103 primary metabolites and 105 secondary metabolites were identified by GC-MS and UPLC-MS, respectively. Fatty acids amounted to a major class in the olive by-products at 53-91%, with oleic acid dominating, especially in the pomace of Siwa. Mill wastewater was discriminated from other by-products by the presence of phenolics mainly tyrosol, hydroxyl tyrosol, and α-tocopherol as analyzed by UPLC-MS indicating their potential antioxidant activity. Pomace and seeds were rich in fatty acids/esters and hydroxy fatty acids and not readily distinguishable from each other. The current work discusses the metabolome profile of olive waste products for valorization purposes. Pomace and seeds were enriched in fatty acids/esters, though not readily distinguishable from each other.

Monitoring the Phenolic and Terpenic Profile of Olives, Olive Oils and By-Products throughout the Production Process.

Olive oil is a food of great importance in the Mediterranean diet and culture. However, during its production, the olive oil industry generates a large amount of waste by-products that can be an important source of bioactive compounds, such as phenolic compounds and terpenes, revalorizing them in the context of the circular economy. Therefore, it is of great interest to study the distribution and abundance of these bioactive compounds in the different by-products. This research is a screening focused on phytochemical analysis, with particular emphasis on the identification and quantification of the phenolic and terpenic fractions. Both the main products of the olive industry (olives, olive paste and produced oil) and the by-products generated throughout the oil production process (leaf, "alpeorujo", liquid and solid residues generated during decanting commonly named "borras" and washing water) were analyzed. For this purpose, different optimized extraction procedures were performed for each matrix, followed by high-performance liquid chromatography coupled with electrospray time-of-flight mass spectrometry (HPLC-ESI-TOF/MS) analysis. Although no phenolic alcohols were quantified in the leaf and the presence of secoiridoids was low, this by-product was notable for its flavonoid (720 ± 20 µg/g) and terpene (5000 ± 300 µg/g) contents. "Alpeorujo" presented a complete profile of compounds of interest, being abundant in phenolic alcohols (900 ± 100 µg/g), secoiridoids (4500 ± 500 µg/g) and terpenes (1200 ± 100 µg/g), among others. On the other hand, while the solid residue of the borras was the most abundant in phenolic alcohols (3700 ± 200 µg/g) and secoiridoids (680 ± 20 µg/g), the liquid fraction of this waste was notable for its content of elenolic acid derivatives (1700 ± 100 µg/mL) and phenolic alcohols (3000 ± 300 µg/mL). Furthermore, to our knowledge, this is the first time that the terpene content of this by-product has been monitored, demonstrating that it is an important source of these compounds, especially maslinic acid (120 ± 20 µg/g). Finally, the phytochemical content in wash water was lower than expected, and only elenolic acid derivatives were detected (6 ± 1 µg/mL). The results highlighted the potential of the olive by-products as possible alternative sources of a wide variety of olive bioactive compounds for their revalorization into value-added products.

Unlocking the potential of olive residues for functional purposes: update on human intervention trials with health and cosmetic products.

Olive mill waste (OMW) is a promising source of valuable compounds such as polyphenols, terpenes, sterols, and other bioactive compounds, which are of interest to the pharmaceuticals and cosmeceutical industries. This review examines the potential of OMW extracts for health and beauty applications based on evidence reports from human clinical trials. The results achieved to date indicate health-enhancing properties, but little is known about the underlying mechanisms of action, dose-response relationships, and long-term impacts. Therefore, while olive by-products, extracted using eco-friendly methods, present opportunities for the development of high-value health and cosmetic products, further studies are necessary to determine the full range of their effects and establish specific therapeutic strategies. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Energy Recovery from Municipal Solid Waste through Co-Gasification Using Steam or Carbon Dioxide with Olive By-Products

The valorization of untreated municipal waste (MSW) biochar for energetic uses, through its co-gasification with olive stone (OST) biochar under a steam or carbon dioxide atmosphere, was investigated. The experiments were conducted in a fixed bed unit and a thermal analysis–mass spectrometer system. The thermal behavior, reactivity, conversion, product gas composition, syngas yield and energy potential were determined, while the influence of the fuel’s internal structure, chemical functional groups and operating conditions were examined. The concentrations of H2 and CO2 in the product gas mixture under a steam atmosphere were increased with steam/biochar ratio, while that of CO was reduced. At a steam/biochar = 3 H2 yield, the higher heating value and conversion for the OST were 52.8%, 10.8 MJ/m3 and 87.5%; for the MSW, they were 44.4%, 9.9 MJ/m3 and 51.5%, whereas for their blend, they were 50%, 10.6 MJ/m3 and 76.6%, respectively. Under a carbon dioxide atmosphere, the reactivity and conversion of the OST biochar (84%) were significantly higher as compared with the MSW biochar (50%). The higher heating value of the product gas was 12.4–12.9 MJ/m3. Co-gasification of the MSW with OST (in proportions 30:70) resulted in the enhanced reactivity, conversion, syngas yield and heating value of product gas compared with gasification of solely MSW material.

Evaluation of Olive Leaf Phenolic Compounds' Gastrointestinal Stability Based on Co-Administration and Microencapsulation with Non-Digestible Carbohydrates.

The large generation of olive by-products has motivated their revalorization into high-added-value products. In this regard, olive leaves pose as an interesting source of bioactive compounds, due to their phenolic content with commonly known antioxidant, anti-inflammatory, and immunomodulatory properties, with potential application in non-communicable diseases. However, their effectiveness and applicability into functional foods is limited by their instability under gastrointestinal conditions. Thus, the development of protective formulations is essential. In this study, the spray-drying encapsulation of a phenolic-rich olive leaf extract with inulin as the encapsulating agent was optimized. Then, the behavior of the free extract under gastrointestinal conditions, its co-administration with the encapsulating agent, and the optimized microencapsulated formulation were studied through an in vitro gastrointestinal digestion process following the INFOGEST protocol. Digestion of the free extract resulted in the degradation of most compounds, whereas this was minimized in the co-administration of the non-encapsulated extract with the encapsulating agent. This protective effect, related to its interaction with inulin, was similar to the microencapsulated formulation. Thus, both approaches, co-administration and microencapsulation with inulin, could be promising strategies for the improvement of the stability of these anti-inflammatory and immunomodulatory compounds under gastrointestinal conditions, enhancing their beneficial effect.

Maximizing hypocholesterolemic peptides from an olive byproduct by enzymatic hydrolysis

Novel food proteases (Maxipro A, Maxipro B, Maxipro C, and Maxipro D) with broad specificity and different effective pH range (from 2.5 to 9.0) were evaluated to produce hypocholesterolemic peptides from olive seeds proteins. Box-Behnken experimental design was employed to evaluate the effect of the hydrolysis time, pH, temperature, and enzyme:substrate ratio on the amount of released peptides. The production of peptides, under optimal conditions, was higher with Maxipro C and lower with Maxipro B. The capability of extracts to reduce the absorption of exogenous cholesterol and the production of endogenous cholesterol was also evaluated. All hydrolysates showed a higher capacity to bind bile acids and inhibit cholesterol esterase enzyme than the obtained with usual Alcalase enzyme. Proteomic analysis using high resolution RP-HPLC-ESI-QTOF with database searching and de novo identification was employed to identify peptides in hydrolysates. Some sequences with hypocholesterolemic features were detected among the 45 peptides identified in Maxipro A hydrolysate, the 56 peptides in that of Maxipro C, and the 50 in the Maxipro B one. This work demonstrates that Maxipro A enzyme can hydrolyze olive seeds proteins, under acidic pH, releasing peptides with multifunctional and higher hypocholesterolemic capacity than the obtained with Alcalase, under alkaline conditions.

Olea europea and By-Products: Extraction Methods and Cosmetic Applications

Currently, in addition to the use of olive oil in cosmetics, the use of olive-derived bioactives and their incorporation into cosmetics is a growing trend. The olive oil industry produces vast quantities of by-products, such as olive mill wastewater, olive pomace and leaves from which new ingredients may be obtained for cosmetic use. In this way, by-products are revalorized, which contributes to the implementation of a sustainable economy or upcycling. This review intends to provide a detailed overview of the different extraction techniques reported in order to obtain the bioactive compounds of cosmetic value that can be found in olive by-products: fatty acids, tocopherols, polyphenols, phytosterols and squalene. Different extraction techniques are presented, including some traditional techniques (solid–liquid extraction) and more novel or “greener” ones: ultrasound, microwave, supercritical extraction, pressurized fluids and deep eutectic solvents. Additionally, different applications of olive by-products in skin care products are explored: emollient, antioxidant, anti-age, anti-inflammatory, antiviral, antifungal and antibacterial, and the perspective of consumers is also considered since they increasingly demand products formulated with natural ingredients.

Exploring the Antioxidant, Neuroprotective, and Anti-Inflammatory Potential of Olive Leaf Extracts from Spain, Portugal, Greece, and Italy.

The leaves of the olive tree (Olea europaea L.) are one of the major solid wastes from the olive industry. Globally, the European Union is the largest producer of olive by-products, with Spain, Italy, Greece, and Portugal accounting for almost the entire production. Many questions remain to be solved concerning olive leaves (OL), including those related to possible differences in composition and/or biological activities depending on their geographical origin. In the present work, OL from Spain, Italy, Greece, and Portugal have been characterized according to their phytochemical profile, antioxidant capacity, neuroprotective activity, and anti-inflammatory effects. The Spanish and Italian OL samples presented the highest antioxidant and neuroprotective activities, while the Greek OL showed the lowest. These results were strongly associated with the content of oleoside methyl ester and p-hydroxybenzoic acid for the Spanish and Italian samples, respectively, whereas the content of decarboxymethyl elenolic acid dialdehyde form (hydrated) was negatively associated with the mentioned biological activities of the Greek samples. No country-related effect was observed in the anti-inflammatory activity of OL. Comprehensively, this work could provide a useful tool for manufacturers and R&D departments in making environmentally friendly decisions on how OL can be used to generate nutraceutical products based on the composition and origin of this by-product.

Thermal Comfort, Growth Performance and Welfare of Olive Pulp Fed Broilers during Hot Season

This study evaluated the nutritional effect of dried olive pulp (OP), on broilers’ thermal comfort, growth parameters and welfare in a commercial poultry farm during the hot season. A number of 108 Cobb male broilers, 19 d olds were allocated into three dietary groups: controls (CON), OP3 and OP6, based on the level of OP added to their diet (0%, 3% and 6%). The thermal comfort of broilers was assessed using the temperature–humidity index (THI). Broilers’ body temperature (BT) was determined weekly. OP beneficially affected the growth performance of broilers undergoing very severe heat stress, as indicated by the increased body weight gain (BWG) recorded in OP groups compared to CON during the first week of the experiment and the higher body weight (BW) of OP fed chickens at 26 d of age (p &lt; 0.05). At 26 d of age, OP6 broilers had lower BT (40.55 ± 0.06 °C) than CON (40.78 ± 0.09 °C) (p &lt; 0.05). A positive dietary effect of OP in welfare parameters like feather cleanliness and panting behaviour of chickens fed 6% OP was also recorded. Using OP as feedstuff is a promising feeding strategy for alleviating the adverse effects of heat stress; it also offers the potential to recycle olive by-products, leading to an efficient waste-based circular economy.

Influence of olive cake dietary supplementation on fecal microbiota of dairy cows.

Olive by-products represent a valuable low-price feed supplement for animal nutrition. In the present study, the effect of the dietary destoned olive cake supplementation, on both composition and dynamics of the fecal bacterial biota of cow, was assessed by Illumina MiSeq analysis of the 16S rRNA gene. In addition, metabolic pathways were predicted by using the PICRUSt2 bioinformatic tool. Eighteen lactating cows, according to the body condition score, the days from calving, and the daily milk production were homogeneously allocated into two groups, control or experimental, and subjected to different dietary treatments. In detail, the experimental diet contained, along with the components of the control one, 8% of destoned olive cake. Metagenomics data revealed significant differences in abundance rather than in richness between the two groups. Results showed that Bacteroidota and Firmicutes were identified as the dominant phyla, accounting for over 90% of the total bacterial population. The Desulfobacterota phylum, able to reduce sulfur compounds, was detected only in fecal samples of cows allocated to the experimental diet whereas the Elusimicrobia phylum, a common endosymbiont or ectosymbiont of various flagellated protists, was detected only in cows subjected to the control diet. In addition, both Oscillospiraceae and Ruminococcaceae families were mainly found in the experimental group whereas fecal samples of control cows showed the presence of Rikenellaceae and Bacteroidaceae families, usually associated with the high roughage or low concentrate diet. Based on the PICRUSt2 bioinformatic tool, pathways related to carbohydrate, fatty acid, lipid, and amino acids biosynthesis were mainly up regulated in the experimental group. On the contrary, in the control group, the metabolic pathways detected with the highest occurrence were associated with amino acids biosynthesis and degradation, aromatic compounds degradation, nucleosides and nucleotides biosynthesis. Hence, the present study confirms that the destoned olive cake is a valuable feed supplement able to modulate the fecal microbiota of cows. Further studies will be conducted in order to deepen the inter-relationships between the GIT microbiota and the host.

Chemical and Rheological Characterization of a Facial Mask Containing an Olive Pomace Fraction

Cosmetic interest in agro-industrial byproducts is growing. In fact, many studies have shown that these residues present bioactive compounds with several skincare applications. One example is olive byproducts, such as olive pomace, which has a composition rich in phenolic compounds. As the production of olive oil is increasing, the amount of byproducts being generated is escalating, with significant constraints in their safe disposal due to their phytotoxic nature. The present study aimed to, from a zero-waste perspective, characterize and add value to a sub-byproduct, a semi-solid paste (SSP) derived from a patent process of olive pomace extraction. The chemical analysis of this residue revealed high moisture and significant protein, fat, and ash contents. Furthermore, vitamin E total phenolics and flavonoid content were assessed, as well as antioxidant activity, using DPPH• (2,2-diphenyl-1-picrylhydrazyl radical) and FRAP (ferric reducing antioxidant power) methods. Based on this primary assessment, a facial mask with antioxidant properties was developed. Rheological analysis showed that the developed mask presented shear thinning behavior, thixotropy, and texture characteristics desirable for skincare use. The results of this study showed the successful incorporation of SSP into facial masks and provides a preliminary assessment of this byproduct’s impact on the appearance and performance of these formulations.

Maximising olive oil by‐products

Maximising olive oil by‐products

Synthesis of Fe-TiO2 and Cu-TiO2 Based Materials by Olive Leaves Biotemplating—Application to Hydrogen Production from Glycerol Photoreforming

Hydrogen production is mainly based on the use of fossil fuels, but currently, many alternative routes are being developed, among which the photo-reforming of oxygenated organic compounds stands out. Recently, several studies have been carried out in order to develop new techniques to create bio-inspired TiO2 structures. One of these is 'biotemplating', a process that replicates a biological system in an inorganic TiO2-based structure. In this study, olive by-products-olive leaves-are valorized as a biotemplate for the synthesis of new Fe-TiO2- and Cu-TiO2-based photocatalysts with the aim of improving the replication of the leaf structure and enhancing hydrogen photoproduction. In conclusion, the incorporation of iron and copper decreases the band gap and increases the energetic disorder at the band edges. Moreover, it is verified by SEM and TEM that the metals are not found forming particles but are introduced into the formed TiO2 structure. The accuracy of the internal and external structure replication is improved with the incorporation of Fe in the synthesis, while the incorporation of Cu substantially improves the production of hydrogen, which is multiplied 14 times under UV light and 6 times under sunlight, as compared to a pure TiO2 structure.

Effect of olive by-products feed supplementation on physicochemical and microbiological profile of Provola cheese.

With the purpose to evaluate the effects of dietary olive cake, a source of bioactive phenolic compounds, as feed supplementation of lactating dairy cows on fatty acid composition, volatile organic compounds, and microbiological profiles of Provola cheese, we performed a two-arm study where control and experimental administered cows derived dairy have been compared. Our panel of analyses include metabolomics, physicochemical detected variables, culture dependent and independent analyses, and a stringent statistical approach aimful at disclosing only statistically significant results. Looking at the physicochemical variable's profiles, a higher content of unsaturated fatty acids, polyunsaturated fatty acid, and conjugated linoleic acids as well of proteins were observed in experimental cheese samples, indicating the beneficial effect of dietary supplementation. Furthermore, based on volatilome composition, a clear cluster separation between control and experimental cheeses was obtained, mainly related to terpenes degradation, able of influencing their aroma and taste. Microbiological results showed a decrease of some spoilage related microbial groups in experimental cheeses, probably due to the inhibitory effect exerted by polyphenols compounds, that contrarily did not affect the core taxa of all cheese samples. This paper confirmed the promising utilization of olive by-product in farming practices to obtain more sustainable and safe dairy food products with lower environmental impact, mainly in Sicily and Mediterranean area, where waste disposal poses serious environmental and economic problems.

SUPPLY CHAINS FOR VALORIZATION OF OLIVE GROVE RESIDUES AND OLIVE OIL INDUSTRY BY-PRODUCTS: A REVIEW ON RESEARCH AND LITERATURE ON OLIVE BASED BIOECONOMY

The residual biomass produced in the olive sector is the result of the large quantity of olive groves and olive oil manufacturers that generate byproducts with a potentially high energy content. Until now, the disposal and management of pruning residues and olive oil by-products has generally represented disposal problems which lead to environmental problems rather than opportunities for additional revenue. In this context, this study aimed to define a roadmap for studies in Turkey to untap the potential of olive grove residues and olive oil industry by-products and residues, (i.e., olive tree prunings, olive leaves, olive pomace) that could be used to produce high-added value products in an integrated biorefinery or in a bioenergy power plant. This paper presents a review on recent research on the valorization of olive by-products in line with the circular economy principles and the bioeconomy strategy and presents the literature which applies to design and management of olive biomass supply chains. Main objective is to provide a conceptual framework for developing and deploying an effective bioeconomy utilizing olive prunings and olive oil industry byproducts conducting a preliminary review of the olive oil chain residues in Europe and Turkey comparatively, assessment of technical potentials, biomass supply costs and allocation of biomass collection sites and energy production facilities with different supply chain scenarios. Biomass resource assessment, biomass feedstock supply chain design and management, and logistics optimization require multidisciplinary and interdisciplinary approaches. They need to be carried out properly in order to execute efficient projects in energy generation from biomass and/or extracting bio-commodities in biorefineries. Turkish researchers have adequate research on valorization methods for olive based biomass resources, but their studies are limited on general biomass supply chain design and particularly no research has been conducted for olive biomass resources. Taking all the aforementioned into account, the author proposes to conduct further studies on a biomass energy project including design of a supply chain network for energy valorization of olive grove residues and olive oil industry by-products in line with the common practice and being inspired by the leading countries like Spain and Italy, which will both contribute to circular business concept development and renewable energy capacity increase.

Healthier Food of Animal Origin and Prevention of Campylobacteriosis

Campylobacter species belong to the most important foodborne bacteria which cause gastroenteritis in humans in both developed and developing countries. Applied hygienic measures result only partially efficient, as demonstrated by the high number of reported cases in the human population. Alternative strategies to prevent the disease though a direct action at primary production level have been explored. Preliminary data showed that cattle and pigs fed with bamboo and olive by-products, respectively, were free from Campylobacter, suggesting potential sustainable prevention strategy. In addition, biochemical analysis showed high levels of unsaturated fatty acids in red meat and meat products, adequate for the application of health claims in line with EU food law.