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The effect of the cold-set and heat-set gelling mechanism of whey protein isolate on bigel production was assessed. For this purpose, hydrogel phase was produced with whey protein isolated (10 % w/v) and for oleogel sunflower oil and glycerol monostearate (7.5 % w/v) were used. Bigels were produced by hot emulsification of different hydrogel:oleogel ratios (from 90:10 up to 10:90). For cold-set bigels (CSB) NaCl (200 mM) was added to the aqueous phase prior to the emulsification and the emulsion was cooled to promote the 3D network formation. On the other hand, heat-set bigels (HSB) were produced by heating the emulsion (80 °C, 60 min). Bigels were evaluated through microscopy, FTIR, thermal and texture analyzes. Results showed that depending on the hydrogel:oleogel ratio and gelling mechanism different structures organization were obtained. CSB were more organized, showing that the rate of gelation was the mechanism responsible for the structure. However, for HSB the heat treatment destabilized the emulsion and disorganized structures were observed for high oleogel content. FTIR corroborates the visual observation and showed that the arrangement was purely physical. In addition, the structural arrangement led to different mechanical properties. In general, HSB produced gels with rubber-like behavior, higher elasticity modulus and the presence of a breaking point. In contrast, CSB behaves as squeezing gel, with no breaking point and lower values of elasticity modulus. Moreover, for O/W bigels the dispersed oleogel particles disrupted the WPI network decreasing the gel strength in comparison to pure hydrogels. However, for systems where oleogel was the continuous phase, the gel strength was recovered due to the metastable and dynamic character of these systems. Thus, results showed that the gelling mechanism of the protein exerted an effect on the physical properties of bigels. In addition, the mechanical properties also can be modulated according to the bigel composition, allowing its application in products with different sensorial characteristics.

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Epidermolysis bullosa (EB) is a group of rare, difficult-to-treat, inherited multisystem diseases affecting epithelial integrity. Impaired wound healing is central and can lead to serious clinical complications, deformities, and symptoms with a devastating impact on quality of life (QoL). Dressing changes and wound care are central to the management of EB. Recently Oleogel-S10 (also known as birch bark extract or birch triterpenes) was approved in Europe and the UK for treating EB wounds. This approval was based on data from the EASE phase 3 study, which demonstrated Oleogel-S10 accelerated wound healing, reduced total wound burden, and decreased the frequency of dressing changes in patients with EB. A retrospective analysis of medical records was conducted for up to 24 months in 13 patients with EB treated with Oleogel-S10 through an early access programme in Colombia. Effectiveness was assessed by measuring body surface area percentage (BSAP) and total body wound burden (EBDASI). Tolerability and safety were monitored throughout. This is the first report to evaluate the effectiveness of Oleogel-S10 in clinical practice. The results showed a reduction in percentage of BSA affected, from a mean of 27.3% at baseline to 10.4% at 24-month follow-up, despite treatment interruptions. A reduction in EBDASI skin activity score of - 16.2 (24 months) together with a reduced skin damage index score of - 15.4 (18 months) was also observed. Physicians, patients, and caregivers perceived faster wound closure. Adherence with therapy by patients was good, and patients expressed satisfaction with treatment and reported improvements in self-esteem, productivity, and social interaction. Oleogel-S10 was well tolerated; however, two patients reported worsening wounds related to gauze adherence. Two deaths during treatment interruption were reported and was not considered related to Oleogel-S10. This study supports the effectiveness of Oleogel-S10 in a real-world scenario in a country with scarce resources for the treatment of EB.

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Fats play multiple roles in determining the desirable characteristics of foods. However, there are health concerns about saturated and trans fats. Bigels have been proposed as a novel fat replacer in foods. This research evaluated the role of the type of hydrogel in the development of bigels to be used as fat replacers in cookies. Bigels were made with beeswax/canola oil oleogel and sodium alginate and carboxymethylcellulose hydrogels. The results showed that the peroxide value and binding capacity of bigels were affected by the type of hydrogel used. However, their fatty acid profile, p-anisidine value, oxidative stability, and texture remained unchanged. Using bigels as fat replacers, cookies were obtained with a hardness similar to those with original shortening, showing the potential of bigels for use in foods.

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In the last decade, food structuring has received considerable attention due to the concern of replacing trans and saturated fats with healthier alternatives without compromising neither technological nor sensorial aspects of food products. Moreover, sustainability topics, consumers' preference for natural ingredients and the molecular architecture displaying a myriad of techno-functionalities embolden the use of proteins. Therefore, a promising approach is to explore this biopolymer as a texture promoter in lipid-based systems, conveying an extra edge in nutritional, sustainable and technological values. A more in-depth comprehension should be cemented to fully harness the potential of proteins in developing soft matter intended for use as fat mimetic. High Internal Phase Emulsion (HIPE), High Internal Phase Pickering Emulsion (HIPPEs), emulgels, oleogels or even bigels can be used in such strategies. Essentially, the formation of such systems relies on the amphiphilic character of proteins. In this sense, the question that arises is how to optimize their solubility in oils to form oil-structured systems? Thus, for oleogel formation the challenge is to overcome the limited dispersibility of proteins in a hydrophobic environment. Therefore, face the growing interest and untapped potential in applying proteins in lipid media, a more wide-ranging picture of their colloidal form (e.g. native, microgels and protein-polysaccharide complexes or conjugates) affecting the structure-function relationship of proteins must be investigated. This review covers different strategies using proteins as building blocks to manufacture different structured systems. Finally, an outlook over the use of protein-based soft matter on an industrial basis is discussed, considering the challenges and perspectives.

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The food industry confronts an enormous challenge to develop stable margarine-type water-in-vegetable oil (W/O) emulsion-based table spreads with reduced concentration of saturated fat and without trans fats. In the present work, we developed a gelled W/O emulsion (Gelled-W/O-E) containing 20% of water using a mixture of a conventional W/O emulsion (W/O-E) stabilized with glycerol monostearate (GMS), and an ethyl cellulose (EC) oleogel. The mechanical, microstructure and stability of the resulting gelled emulsion (Gelled-W/O-E) was compared with control systems consisting of conventional W/O emulsions (W/O-E) and EC-GMS oleogels (EC-GMS-O; no water added) formulated using the same GMS (0.5% and 1.0%) and EC (7%) concentration as in the Gelled-W/O-E. The Gelled-W/O-E showed higher elasticity and emulsion stability in comparison with the control systems. This in spite the EC and GMS concentrations used were below the minimal concentration required to develop a gel, and the tentatively lower solid content in the Gelled-W/O-E than in the EC-GMS-O because the presence of water. We observed that by increasing the GMS concentration in the Gelled-W/O-E, the water droplet size decreased as gel elasticity and W/O emulsion stability significantly increased. We associated this behavior to a synergistic GMS-EC interaction that kept the GMS at the water-oil droplet interface. These results showed the role of water droplets as active fillers in determining the rheological properties of the Gelled-W/O-E, and that the GMS efficiency as emulsifier increased in the presence of EC in the oil phase. After comparing the microstructural properties of commercial margarine spreads with those of the Gelled-W/O-E, we concluded that the structured W/O emulsion is a novel way to achieve similar functionality to margarine spreads, without the use of saturated and trans-fats.

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Coenzyme Q10 (CoQ10) supplementation has demonstrated to be safe and effective in primary and secondary CoQ10 deficiencies. Previously, we have designed a high-dose CoQ10 oleogel (1 g/disk) with excipients used in quantities that do not represent any toxic risk. However, it was necessary to demonstrate their safety in the final formulation. Following this purpose, an acute toxicity study of the oleogel in rats was performed. Furthermore, the genotoxic risk was evaluated in human volunteers after CoQ10 supplementation with oleogel and compared to the solid form (1 g/three 00-size-capsules). In addition, the general health status and possible biochemical changes of the participants were determined using serum parameters. Results suggested the absence of adverse effects caused by the interaction of the components in the oleogel formulation. Therefore, we conclude that the designed novel high-dose CoQ10 oleogel was safe for oral consumption.

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This review discusses the application of oleogel technology in emulsified systems. In these systems of mimetic fats, water-in-oil or oil-in-water emulsions can be obtained, but, here, we cover emulsions with an oil continuous phase in detail. Depending on the percentage of water added to the oleogels, systems with different textures and rheological properties can be developed. These properties are affected by the characteristics and concentration of the added components and emulsion preparation methods. In addition, some gelators exhibit interfacial properties, resulting in more stable emulsions than those of conventional emulsions. Oleogel-based emulsion are differentiated by continuous and dispersed phases and the structuring/emulsification components. Crucially, these emulsions could be applied by the food industry for preparing, for example, meat products and margarines, as well as by the cosmetics industry. We present the different processes of emulsion elaboration, the main gelators used, the influence of the water content on the structuring of water-in-oleogel emulsions, and the structuring mechanisms (Pickering, network, and combined Pickering and network stabilization). Finally, we highlight the applications of these systems as alternatives for reducing processed food lipid content and saturated fat levels.

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Bologna sausages were produced with 25, 50, 75 and 100% of their pork fat content replaced by monoglyceride based-oleogels prepared from conventional or high oleic sunflower oils. Physicochemical, technological, and sensory properties of Bologna sausages were evaluated. Emulsion stability was little affected by fat replacement. All treatments batters exhibited characteristic rheological properties of gels (G' > G″). Overall, the addition of oleogel as a fat substitute made the sausages lighter and a small increase in hardness was observed in the sausages with total fat replacement by oleogels. The sliceability was affected by the reformulation and a higher number of slices were obtained in samples with oleogels in relation to the control. These results were associated to the product structure that became more compact as the amount of pork fat was reduced. However, all samples showed good acceptance by the consumers and no significant difference was observed between treatments. The results showed that monostearate-based oleogel can be a potential fat replacer with higher amount of unsaturated fatty acids to be used in meat products, but retaining the desired characteristics of the traditional products.

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The gelation process, elasticity, and mechanical recovery after shear were studied in mixed oleogels of ethylcellulose (EC), monoglycerides (MG), and candelilla wax (CW). EC oleogels produced without MG showed grainy texture due to incomplete dissolution of crystalline fractions of raw EC in the vegetable oil (150 °C). These fractions were eliminated by dissolving the raw EC/MG mixture in ethanol, evaporating the solvent, dispersing, and dissolving the solid residue in the vegetable oil (150 °C) prior gelation. The EC polymeric network, and MG, and CW crystals had a positive interaction on the elasticity of mixed oleogels. Mixed oleogels produced under static conditions showed a 100 % of elasticity recovery after shearing, a phenomenon associated with an EC interchain hydrogen bonding mediated by hydroxyl groups of MGs. This tentatively resulted from the formation of junction zones of the type EC-[MG]n-EC. The rheological behavior of these olegels was remarkably close to that of commercial shortenings.

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Diante das exigências crescentes das agências regulatórias do mundo todo quanto à redução/eliminação de ácidos graxos trans nos alimentos industrializados, bem como da conscientização do consumidor sobre a relação entre alimentação e saúde, o desenvolvimento de alternativas mais saudáveis aos óleos parcialmente hidrogenados e a outras fontes lipídicas com alto grau de saturaçã o se faz necessário. O oleogel, um sistema composto por um óleo preso em uma rede tridimensional formada por um agente estruturante, se apresenta como uma solução promissora. Dentre os diversos agentes estruturantes, as ceras vegetais se destacam por sua excelente capacidade de gelificação de óleos. Contudo, apresentam uma desvantagem sob o aspecto sensorial, pois podem conferir cerosidade e sabor residual desagradável aos alimentos. Com o objetivo de viabilizar o uso das ceras como agentes estruturantes em oleogéis face ao seu excelente desempenho tecnológico, este projeto propõe o estudo e a aplicação de oleogéis à base de óleo de soja (SBO) estruturado com ceras de farelo de arroz (RBW) a 2 e 4 % (m/m) ou carnaúba (CBW) a 3 e 6% (m/m), isoladamente. As matérias-primas foram caracterizadas e o comportamento de gelificação de cada cera foi avaliado por análises de textura por penetração de cone, estabilidade à perda de óleo por centrifugação, energia coesiva por parâmetro de solubilidade de Hansen (HSP) e comportamento de cristalização e fusão por calorimetria exploratória diferencial (DSC). Os resultados mostraram que ambas as ceras são capazes de formar oleogéis estruturalmente estáveis, contudo, o oleogel com 2% de RBW apresentou maior firmeza a 20 °C (190,4 gf/cm2) do que o oleogel com 6% de CBW a 5 °C (186,1 gf/cm2). Ao final de 5 dias, a capacidade de retenção de óleo do oleogel preparado com RBW foi de 100% às concentrações de 2 e 4% (m/m), contra 61 e 99,3% do oleogel elaborado com CBW às concentrações de 3 e 6% (m/m), respectivamente. Esses resultados podem ser explicados pela diferença entre as energias coesivas, ou seja, do grau de interação molecular entre o solvente e o soluto de cada oleogel. De acordo com os resultados de distância, que prevê se o gel formado será forte, fraco ou se não haverá formação de gel, o soluto CBW apresentou menor interação com o óleo (3,3 MPa1/2) do que o soluto RBW (3,7 MPa1/2). Os oleogéis foram aplicados como ingredientes em diferentes formulações de cream cheese, que foram analisados quanto a diferentes parâmetros de textura e esses resultados foram comparados a uma referência comercial. Nenhuma das amostras produzidas obteve resultados de textura estatisticamente iguais aos do cream cheese comercial (CC), o que pode ser explicado pelas diferenças de formulação e processamento dos produtos. Face aos resultados para textura e estabilidade à perda de óleo dos oleogéis de RBW, este agente estruturante apresenta ria maior potencial de aplicação, porém o oleogel CBW6 obteve alta capacidade de retenção de óleo (99,3%) e quando aplicado na formulação de cream cheese (CCBW6) apresentou resultados de firmeza e espalhabilidade mais próximos da amostra de referência, feita com gordura do leite (CMF)

Given the growing demands of regulatory agencies around the world regarding the reduction/elimination of trans fatty acids in processed foods, as well as consumer awareness about the relationship between food and health, the development of healthier alternatives to partially hydrogenated oils and others lipid sources with a high degree of saturation are necessary. Oleogel, a system composed of an oil trapped in a three-dimensional network formed by a structuring agent, presents itself as a promising solution. Among the various structuring agents, vegetable waxes stand out for their excellent oil gelling capacity. However, they have a sensory disadvantage, as they can give waxy and unpleasant aftertaste to foods. Aiming at enabling the use of waxes as structuring agents in oleogels in view of their excellent technological performance, this study proposes the evaluation and application of oleogels based on soybean oil (SBO) structured with rice bran wax (RBW) at 2 and 4% (m/m) or carnauba (CBW) at 3 and 6% (m/m). The raw materials were characterized and the gelling behavior of each wax was evaluated by analysis of texture by cone penetration, stability to oil loss by centrifugation, cohesive energy by Hansen solubility parameter (HSP) and crystallization and melting behavior. by differential scanning calorimetry (DSC). The results showed that both waxes are able to form structurally stable oleogels, however, oleogel with 2% RBW showed greater firmness at 20 °C (190.4 gf/cm2) than oleogel with 6% CBW at 5° C (186.1 gf/cm2). At the end of 5 days, the oil retention capacity of oleogel prepared with RBW was 100% at concentrations of 2 and 4% (m/m), against 61 and 99.3% of oleogel prepared with CBW at concentrations of 3 and 6% (m/m), respectively. These results can be explained by the difference between the cohesive energies, that is, the degree of molecular interaction between the solvent and the solute of each oleogel. According to the distance results, which predicts if the formed gel will be strong, weak or if there will be no gel formation, the CBW solute showed less interaction with the oil (3.3 MPa1/2) than the RBW solute (3 ,7 MPa1/2). Oleogels were applied as ingredients in different cream cheese formulations, which were analyzed for different texture parameters and these results were compared to a commercial reference. None of the samples produced had texture results statistically equal to those of commercial cream cheese (CC), which can be explained by the differences in formulation and processing of the products. Given the results for texture and oil binding capacity of RBW oleogels, this structuring agent would present greater application potential, but CBW6 oleogel obtained high oil biding capacity (99.3%) and when applied in cream cheese formulation (CCBW6) showed firmness and spreadability results closer to the reference sample, made with milk fat (CMF)

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Coenzyme Q10 (CoQ10) is essential in mitochondrial bioenergetics and is a potent endogenous antioxidant. Low CoQ10 levels are associated with neurodegenerative, metabolic, muscular and cardiovascular disorders. Early treatment with high doses (5-50 mg/kg/day) demonstrated to limit the onset and progression of neuropathology. Recently, we developed an oleogel matrix able to support a high dose of oil-dissolved CoQ10, easy to swallow by CoQ10-deficient patients who suffer from secondary dysphagia. In the present study, we evaluated the bioavailability of oleogel-dissolved CoQ10 and plasma antioxidant status in healthy adults in single-dose and repeated-dose studies. The single-dose study demonstrated that, in terms of CoQ10 bioavailability, 1 g CoQ10/5g oleogel-disk was equivalent to the solid form (1 g CoQ10/three 00-size-capsules), whereas the repeated-dose study (14-days-administration) demonstrated a significantly higher increase in plasma CoQ10 when administered through the oleogel, which could be compatible with the levels necessary to achieve an adequate therapeutic response. Also, a trend to a higher plasma apparent half-life (greater than24 h) was observed for the oleogel-loaded-CoQ10. In conclusion, the oleogel matrix does not compromise the oil-dissolved CoQ10 bioavailability and can prevent the non-adherence to this vital supplementation in patients with high CoQ10 requirements. No significant variation in the plasma antioxidant status (vitamins A, E and C, glutathione and TBARs) was observed.

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BACKGROUND: Maize tortilla staling is a major drawback that affects its commercialization and consumption, and so novel methods for retarding staling are continuously being explored. The present study evaluated the effect of adding a canola oil/candelilla wax oleogel (CWO; 0. 2, 4 and 6 g 100 g-1 ) to a basic masa formulation (water, 60 g 100 g-1 ; nixtamalized maize flour, 40 g 100 g-1 ) on the texture, staling and in vitro starch digestibility of maize tortillas made using a hot plate (200 °C). RESULTS: Textural analysis showed that CWO reduced hardness and increased the tensile strength of tortillas. Fourier transform infrared analysis indicated that the retrogradation of starch chains, quantified in terms of the intensity ratio 1047/1022, was reduced by oleogel incorporation. In vitro starch digestibility tests showed that tortillas containing CWO had lower readily digestible and slowly digestible starch fractions compared to the control tortilla without oleogel. CONCLUSION: The formation of amylose-lipid inclusion complexes and the formation of an oily physical barrier around starch granules were postulated as mechanisms underlying the reduced starch digestibility. © 2019 Society of Chemical Industry.

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A crescente rejeição às gorduras saturadas e trans em decorrência de sua associação com doenças cardiovasculares, entre outras desordens metabólicas de diversas naturezas, tem impulsionado o desenvolvimento de alternativas às gorduras tradicionalmente utilizadas nos processamentos de alimentos. Contudo, o grande desafio reside em conferir funcionalidade tecnológica a lipídios ricos em ácidos graxos insaturados, sendo os oleogéis uma abordagem viável e promissora. Os oleogéis são sistemas constituídos por uma base lipídica composta por óleo no estado líquido estruturada por uma rede tridimensional de moléculas com solubilidade limitada em óleos, chamadas de agentes estruturantes. Estudos recentes relataram a influência do tipo de óleo no processo de formação da rede tridimensional de agentes estruturantes e concluíram que o tamanho da cadeia, a polaridade e a viscosidade do óleo podem afetar grandemente a estrutura do oleogel. Diante disto, o objetivo deste estudo é investigar a influência do tipo de óleo em sua estruturação por cera de candelilla, relacionando as propriedades físicas dos oleogéis formados com diversas características físico-químicas dos óleos que os compõem. Para avaliar esta influência, foram selecionadas bases lipídicas de diferentes composições, como triacilgliceróis de cadeia média (MCT), óleo de girassol alto oleico (HOSO), óleo de girassol (SFO), óleo de linhaça (LSO) e os óleos unicelulares ARASCO e DHASCO, para serem estruturados com cera de candelilla nas concentrações de 1,5, 3,0 e 6,0%. De acordo com as correlações de Pearson estabelecidas, houve uma correlação muito forte (r2 =0,948) entre a firmeza e o conteúdo de ácidos graxos saturados dos óleos, o que pode estar relacionado a uma co-cristalização entre a cera e os ácidos graxos saturados, formando uma estrutura mais firme. Uma correlação forte também foi estabelecida entre o tamanho médio das cadeias de ácidos graxos dos óleos, definido pelo índice de saponificação, e a firmeza dos oleogéis (r2 =0,864). A densidade dos óleos também apresentou correlação forte com a firmeza dos oleogéis (r2 =0,858), assim como a viscosidade apresentou uma forte correlação negativa (r2 = -0,818), o que indica que os óleos mais densos e menos viscosos produzem oleogéis mais firmes. Tanto a cera de candelilla pura quanto os oleogéis apresentaram forma polimórfica ß', que equivale à subcélula ortorrômbica, que demonstra que os diferentes óleos não modificaram a microestrutura da rede de cera de candelilla. Os diferentes tipos de óleo exerceram influência sobre o comportamento de fusão dos oleogéis, fator que permitiu associá-lo a um maior conteúdo de gordura sólida a 20 °C e a um maior teor de triacilgliceróis trissaturados, como nos óleos DHASCO e ARASCO. O grau de insaturação dos óleos influenciou o empacotamento da rede estrutural dos oleogéis, o que foi revelado pela menor perda de óleo nos oleogéis com cadeias mais longas, se comparados ao MCT. Por fim, este trabalho contribuiu com a expansão do conhecimento dos sistemas chamados oleogéis, sugerindo que trabalhos futuros pautem as escolhas de matéria-prima para formulação dos oleogéis nas propriedades de seus componentes. Desta forma, maiores avanços poderão ser alcançados nas pesquisas de sistemas coloidais e consequentemente no desenvolvimento de sistemas de alta qualidade nutricional e, ao mesmo tempo, funcionalidade tecnológica adequada

The growing rejection of saturated and trans fats as a result of their association with cardiovascular diseases, among other metabolic disorders of various kinds, has driven the development of alternative systems to substitute fats traditionally used in food processing. However, the big challenge lies in providing technological functionality to lipids rich in unsaturated fatty acids, with oleogels being a viable and promising approach. Oleogels are systems made up of a lipid base composed of oil in a liquid state structured by a threedimensional network of molecules with limited solubility in oils, called oleogelators. Recent studies have reported the influence of the oil type in the formation process of the threedimensional network of oleogelators and concluded that the fatty acid chain length, the polarity and the viscosity of the oil can greatly affect the structure of the oleogel. In view of this, the objective of this study is to investigate the influence of the oil type in its structuring by candelilla wax, relating the physical properties of the formed oleogels with several physicochemical characteristics of the oils that compose them. To evaluate this influence, lipid bases of different compositions were selected, such as medium chain triglycerides (MCT), high oleic sunflower oil (HOSO), sunflower oil (SFO), linseed oil (LSO) and ARASCO and DHASCO single-cell oils, to be structured with candelilla wax in concentrations of 1.5, 3.0 and 6.0% (w/w). According to the Pearson correlations established, there was a very strong correlation (r2 = 0.948) between the firmness and the saturated fatty acid content of the oils, which may be related to a co-crystallization between the wax and the saturated fatty acids, forming a firmer structure. A strong correlation was also established between the average size of the fatty acid chains of the oils, defined by the saponification value, and the oleogel firmness (r2 = 0.864). The density of the oils also showed a strong correlation with the firmness of the oleogels (r2 = 0.858), as well as the viscosity, which showed a strong negative correlation (r2 = -0.818), indicating that oils with higher density and lower viscosity produce firmer oleogels. Both pure candelilla wax and oleogels presented the ß' polymorphic form, which is equivalent to the orthorhombic subcell, demonstrating that the different oils did not modify the microstructure of the candelilla wax network. The different types of oil influenced the melting behavior of oleogels, a factor that allowed it to be associated with a higher solid fat content at 20 °C and a higher content of trisaturated triacylglycerols, as in DHASCO and ARASCO oils. The degree of unsaturation of the oils influenced the packaging of the structural network of oleogels, which was revealed by the higher oil binding capacity in oleogels with longer chains, compared to MCT. Finally, this work contributed to the expansion of knowledge of oleogel systems, suggesting that future work will guide the choices of raw material for formulating oleogels in the properties of their components. Thus, greater advances can be achieved in the research of colloidal systems and, consequently, in the development of high nutritional quality systems allied to adequate technological functionality

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RESUMO

As gorduras ricas em ácidos graxos saturados e/ou trans são ingredientes que brindam propriedades nos alimentos como textura, fusão e estabilidade. Porém, a relação entre seu consumo e enfermidades cardiovasculares, força a busca de novas alternativas. Uma alternativa potencial são os oleogéis, pois são um material plástico e com melhor balanço lipídico, do ponto de vista nutricional. Os oleogéis são sistemas coloidais onde uma fase orgânica líquida, representada por um óleo, é imobilizada por uma rede sólida tridimensional formada por agentes estruturantes. Atualmente, tem sido estudados oleogéis conformados com variados agentes estruturantes, com o intuito de encontrar a melhor opção. Além disso, alguns estudos indicam que o uso combinado de dois ou mais agentes estruturantes pode resultar no aumento de seu potencial de estruturação de óleos ou na possibilidade de customizar as propriedades adequadas para produção alimentar. Assim, o objetivo deste estudo é avaliar a interação entre os componentes de oleogéis preparados com óleo de girassol alto oleico (HOSO), como base lipídica, e combinações de cera de candelilla (CW) e monoestearato de sorbitana (SMS), como agentes estruturantes. A avaliação dos oleogéis por meio dos diagramas de fases e a consistência, mostrou que há uma sinergia entre os componentes, na concentração de 8 e 4% de agentes estruturantes e 79-89% de cera de candelilla. Estes oleogéis mistos tiveram uma faixa de fusão maior do que os oleogéis não mistos. Sugerindo a construição de cristais mais estáveis, que demoraram mais tempo em fundir. A capacidade de retenção de óleo se mostrou adequada (99%) nas amostras contendo mais de 1% de agentes estruturantes e com mais de 40% de Cera de Candelilla. Nas imagens obtidas por PLM, foi observada uma variedade de tamanho de cristais, sugerindo que cada componente do oleogel formou um tipo de cristal. Com a elaboração de bigéis, foi notado que, para obter um produto satisfatoriamente espalhável ou para observar o aumento de sua consistência em comparação com o oleogel isoladamente, é necessária uma concentração maior do que 4% de agentes estruturantes no oleogel e/ou a adição de menos de 20% de água na formulação total. A estabilidade dos bigéis foi beneficiada pela goma xantana e pela mistura de 2:1 de goma xantana e goma guar na concentração de 0,3%. Dessa forma, o desenvolvimento de alimentos com teores reduzidos de gorduras saturadas e ao mesmo tempo livres de gorduras trans se faz possível com a formulação de oleogéis, o que poderá contribuir para melhorar a qualidade nutricional dos alimentos industrializados oferecidos à população

Fats rich in saturated and / or trans fatty acids provide properties in food such as texture, fusion and stability. But, since those fats increase cardiovascular disease risk, alternatives have been searched. A potential alternative is oleogels, as they are a plastic material with better lipid balance from a nutritional point of view. Oleogels are colloidal systems where a liquid organic phase, represented by an oil, is immobilized by a three-dimensional solid network formed by structuring agents. Currently, oleogels conformed with various structuring agents have been studied in order to find the best option. In addition, some studies indicate that the combined use of two or more structuring agents may result in increased oil structuring potential or the possibility of customizing the properties suitable for food production. Thus, the aim of this study is to evaluate the interaction between the components of oleogels prepared with high oleic sunflower oil (HOSO) as a lipid base and combinations of candelilla wax (CW) and sorbitan monostearate (SMS) as structuring agents. The evaluation of oleogels by phase diagrams and consistency (Yield value) showed that there is a synergy between the components, in the concentration of 8 and 4% of structuring agents and 79-89% of candelilla wax. These mixed oleogels had a higher melting range than unmixed oleogels. Suggesting the construction of more stable crystals, which took longer to fuse. Oil binding capacity was adequate (99%) in samples containing more than 1% of structuring agents and over 40% of candelilla wax. In the PLM images, a variety of crystal sizes were observed, suggesting that each oleogel component formed a crystal type. With the elaboration of bigels, it was noted that in order to obtain a satisfactorily spreadable product or to observe the increase of its consistency compared to the oleogel alone, a concentration greater than 4% of structuring agents in the oleogel and / or the addition of less than 20% water in the total formulation. The stability of the bigels was benefited by xanthan gum and the 2: 1 mixture of xanthan gum and guar gum at a concentration of 0.3%.Thus, the development of foods with reduced levels of saturated fat and at the same time free of trans fats is possible with the formulation of oleogels, which may contribute to improve the nutritional quality of processed foods offered to the population

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RESUMO

In this study the effect of lecithin (L) addition and solvent quality in a well-established oleogel system formed by ß-sitosterol and γ-oryzanol (BG) was investigated. Medium chain triglycerides (MCT) and sunflower oil (SFO) were used as triglycerides and hexadecane (HEX) as a model of linear hydrocarbon. Lecithin was proposed due to its natural and versatile properties, showing different functionalities such as emulsifier and co-oleogelator. A study based on hierarchical organization of structured oil was performed applying techniques for bulk, meso and nanoscale. Self-sustained structures could no longer be observed after 40 wt% of BG replacement by lecithin. Small-angle X-ray scattering showed that the formed nanostructures (building blocks) were dependent on type of solvent and BG:L ratio in the mixture of oleogelators. Differential scanning calorimetry showed that stability against temperature was improved decreasing the polarity of the oil, and a time-dependent self-assembly of hybrid systems was observed from thermal and rheological measurements. Microscopy images exhibited changes on typical fibril aggregation of BG as lecithin was added, which promoted to a certain extent the suppression of ribbons. Oscillatory shear and uniaxial compression measurements were influenced by BG:L ratio and solvent mainly at higher lecithin amount. The combination of BG and MCT appeared to be the most affected by lecithin incorporation whereas SFO rendered harder oleogels. These results could contribute to understand the role of both lecithin and solvent type influencing the host oleogelator structure. It was hypothesized that intermolecular BG complex formation is hindered by lecithin, besides this phospholipid also might coexist as a different phase, causing structural changes in the gel network. Addressing the role of co-oleogelator it can provide the opportunity to tune soft materials with adjusted properties.

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