Enrichment of Refined Olive Oils with Phenolic Extracts of Olive Leaf and Exhausted Olive Pomace

Stability, chromatic characteristics and chemical changes of sacha inchi (Plukenetia huayllabambana) oil enriched with aguaje oil (Mauritia flexuosa L.f.) rich in carotenoids

Sacha inchi (Plukenetia huayllabambana) oil is a food matrix that contains more than 80 % of polyunsaturated fatty acids, especially linoleic and α-linolenic acids. The objective of this study was to develop blends of sacha inchi oil (P. huayllabambana) enriched with aguaje oil (Mauritia flexuosa L.f.) and evaluate the induction period, total carotenoid content, nutritional quality indices and oxidative stability from the fatty acid composition. The analytical tests were conducted for oil blends that had the following proportions: sacha inchi oil enriched with aguaje oil at 5, 10 and 20 %. The results prove that the enrichment of sacha inchi oil with aguaje oil (SIO-PH-AO) leads to an improvement in oxidative stability and nutritional and physical properties. For example, the oxidative stability index (OSI) varied from 0.87 to 2.53 h. The content of total carotenoids produces an increase from 0.35 to 99.90 mg/kg, while total polyphenols from 47.45 to 126.90 mg GAE/g, and chroma from 39.91 to 69.02 units. Regarding the fatty acid profile, the oxidizability value improves with the addition of aguaje oil. Reduces levels of PUFA, PUFA/SFA, and hypo-and hypercholesterolemic ratio (h/H). Additionally, an increase in SFA and MUFA levels, while the ω6/ω3 ratio remained constant. Finally, it can be noted that the enrichment of sacha inchi oil with aguaje oil (rich in carotenoids) provides better stability and can be used for commercial applications as a mechanism to establish new vegetable oils with better properties.

Oleocanthal - Characterization, production, safety, functionality and in vivo evidences

Oleocanthal, OC, 2-(4-Hydroxyphenyl)ethyl(3S,4E)-4-formyl-3-(2-oxoethyl)hex-4-enoate, is a natural organic compound exclusively found in Olea europaea L. (Oleoaceae), such as extra virgin olive oil (EVOO). Chemically, it is considered a monophenolic secoiridoid, taking part of the validated antioxidants naturally occurring in some plant-based foods. In this review, the aim is to summarize the identity and characteristics of this molecule, where it can be obtained (isolation from the natural source or chemical synthesis), as well as the use as food component. Then, the bioavailability, safety and studies aiming to demonstrate the potential health benefits, including in vitro and in vivo animal and human studies were also discussed.

Optimization of Conditions for Microwave-Assisted Extraction of Polyphenols from Olive Pomace of Žutica Variety: Waste Valorization Approach

Olive pomace is a by-product of olive oil production that is toxic to the environment. The purpose of this study was to evaluate the methods of olive pomace valorization through the implementation of novel technology, the so-called microwave-assisted extraction process. To determine the total polyphenol content (TPC) and antioxidant activity (AA), polyphenol extraction using MAE was performed. Response surface methodology was used to determine the best extraction conditions, whereby the effects of three factors, solid ratio (g/50 mL), time (s), and power (W), were measured. The ferric reducing antioxidant power (FRAP) method was used to assess AA, whereas the spectrophotometric Folin-Ciocalteu (FC) method was used to determine TPC. The highest TPC of 15.30 mg of gallic acid equivalents per gram of dried weight (mg GAE/gdw) was generated after 105 s at 450 W, with a solid concentration of 1 g/50 mL, while the maximum AA was 10 mg of ascorbic acid equivalents per gram of dried weight (mg AAE/gdw). Numerical optimization revealed that 800 W, 180 s, and 1 g/50 mL were the best conditions for obtaining maximum TPC and AA.

Role of Olive Bioactive Compounds in Respiratory Diseases

Respiratory diseases recently became the leading cause of death worldwide, due to the emergence of COVID-19. The pathogenesis of respiratory diseases is centred around inflammation and oxidative stress. Plant-based alongside synthetic drugs were considered as therapeutics due to their proven nutraceutical value. One such example is the olive, which is a traditional symbol of the MedDiet. Olive bioactive compounds are enriched with antioxidant, anti-inflammatory, anticancer and antiviral properties. However, there are few studies relating to the beneficial effect of olive bioactive compounds on respiratory diseases. A vague understanding of its molecular action, dosage and bioavailability limits its usefulness for clinical trials about respiratory infections. Hence, our review aims to explore olive bioactive compound's antioxidant, anti-inflammatory and antiviral properties in respiratory disease defence and treatment. Molecular insight into olive compounds' potential for respiratory system protection against inflammation and ensuing infection is also presented. Olive bioactive compounds mainly protect the respiratory system by subsiding proinflammatory cytokines and oxidative stress.

In vivo evidences of the health-promoting properties of bioactive compounds obtained from olive by-products and their use as food ingredient

Olea europaea L. is the source of virgin olive oil (VOO). During its extraction, a high amount of by-products (pomace, mill wastewaters, leaves, stones, and seeds) is originated, which possess an environmental problem. If the generation of waste cannot be prevented, its economic value must be recovered and its effects on the environment and climate change must be avoided or minimized. The bioactive compounds (e.g., phenols, pectins, peptides) of these by-product fractions are being investigated as nutraceutical due to the beneficial properties it might have. In this review, the aim is to summarize the in vivo studies carried out in animals and humans with bioactive compounds exclusively obtained from olive by-products, aiming to demonstrate the potential health benefits these products can exert, as well as to describe its use in the food industry as bioactive ingredient. Several food matrices have been fortified with olive by-products fractions, leading to an improvement of properties. Animal and human studies suggest the benefits of ingesting olive-derived products to promote health. However, the investigation until now is scarce and consequently, well-designed human studies are required in order to fully address and confirm the safety and health-promoting properties of olive oil by-products.

Co-Extraction Technique Improves Functional Capacity and Health-Related Benefits of Olive Oils: A Mini Review

Olive oil, a fundamental component of the Mediterranean diet, is recognized as a functional food due to its health-promoting composition. The concentration of phenolic compounds in olive oil is influenced by various factors such as genetics, agro-climatic conditions, and technological processes. Therefore, to ensure an ideal intake of phenolics through the diet, it is recommended to produce functional enriched olive oil that contains a high concentration of bioactive compounds. The co-extraction technique is used to create innovative and differentiated products that promote the sensory and health-related composition of oils. To enrich olive oil, various natural sources of bioactive compounds can be used, including raw materials derived from the same olive tree such as olive leaves, as well as other compounds from plants and vegetables, such as herbs and spices (garlic, lemon, hot pepper, rosemary, thyme, and oregano). The development of functional enriched olive oils can contribute to the prevention of chronic diseases and improve consumers' quality of life. This mini-review compiles and discusses relevant scientific information related to the development of enriched olive oil using the co-extraction technique and its positive effects on the health-related composition of oils.

The Chemical, Rheological, and Sensorial Characteristics of Arabic Bread Prepared from Wheat-Orange Sweet Potatoes Flour or Peel

The current study investigates the feasibility of preparing Arabic bread from wheat flour, sweet potato flour, or peeled sweet potatoes based on the nutritional values, technological characteristics, and sensory properties of the final products. First, we analyzed the proximate, elemental, total and individual phytochemical compositions of the raw materials and bread samples. The analysis showed that potassium, calcium, and phosphorus were higher in peels than pulp, in the same manner to the total phenolics, flavonoids, and anti-radical scavenging activities. Phenolic acids and flavonols were quantified, where p-coumaric, feruloyl-D-glucose, eucomic, gallic, and ferulic acids were measured as major phenolic acids in either peels or pulp flours, and their quantities were higher in the peels. Furthermore, we evaluated the effects of wheat substitution on the properties of the dough blends and their final bakery. The results indicated that the fortified samples' nutritional and rheological properties were significantly improved, while their sensory qualities were comparable to those of the control. Thereby, the fortified dough blends presented higher dough stabilities, indicating a wider range of applications. Additionally, after the heat treatment, the fortified breads maintained significantly higher total phenolic, flavonoid, anthocyanin, and carotenoid contents, and total antioxidant activities, implying their accessibility for humans upon consumption.

Hepatopreventive properties of hydroxytyrosol and mannitol-rich extracts obtained from exhausted olive pomace using green extraction methods

Hydroxytyrosol and mannitol rich extracts from exhausted olive pomace were obtained by green extraction methodologies. Supplementation of these extracts alleviated CCl4-induced hepatic damage and protected DNA.