En el presente trabajo se ha estudiado el comportamiento viscoelástico lineal de las fases micelares y líquido-cristalinas presentes en el diagrama de fases del sistema aducto de nonilfenol con dies moles de óxido de etileno (NPFE-10) y agua. Con este propósito se efectuaron ensayos en cizalla oscilatoria no destructivos dentro del intervalo de viscoelasticidad lineal. Las funciones viscoleásticas obtenidas para las fases micelar y hexagonal pueden describirse satisfactoriamente mediante modelos de Maxwell simple y generalizado, respectivamente. el comportamiento viscoelástico linal de la fase laminar es el típico de fluidos altamente estructurados, obteniéndose una zona plateau en el intervalo de frecuencias estudado. Por otra parte, de los resultados experimentales se deduce qu los ensayos viscoelásticos lineales constituyen un método eficaz a la hora de determinar las transiciones de fases micelares y/o líquido-cristalinas

A poluição das fontes de água por compostos fenólicos é um problema na sociedade contemporânea associado a uma expectativa de alto consumo deste recurso. A destilação com membranas por contato direto (DMCD) tem atraído a atenção para aplicações no tratamento de água e remoção de micropoluentes, devido a sua estabilidade, modularidade e robustez. Além disso, ela pode ser associada à fontes de energia alternativas como as renováveis e calor residual. Nesse contexto, buscando soluções para problemas estabelecidos, esse trabalho estudou a remoção de compostos fenólicos em água superficial pela DMCD. Para tanto, foi realizada uma pesquisa de revisão de literatura (2000-2023), que constatou a ocorrência de mais de 60 fenóis nas fontes de água de diversos países em concentrações variando de <0,065 a 179 M ng L-1. Os riscos para a saúde humana foram estimados com as concentrações reportadas na literatura, mostrando resultados preocupantes para alguns fenóis, tais como 2-nitrofenol, 2,6-diclorofenol, 3,4,5-triclorofenol, 2,3,4,6-tetraclorofenol, 2,4-dinitrofenol, 3-metilfenol, 2,4-dimetilfenol, 2,4,6-triclorofenol e pentaclorofenol. A importância do setor de tratamento de água na remoção destes micropoluentes foi ressaltada, assim como a incorporação de mais composto fenólicos nas diretrizes de água potável para proteção das populações. As possibilidades de remoção de fenóis pelas tecnologias de membranas foram elencadas, sendo destacadas as altas remoções da osmose inversa, como uma tecnologia madura e com a menor pegada ecológica estimada, e da destilação por membrana, como uma tecnologia emergente. Experimentos foram feitos utilizando a DMCD em escala de bancada para avaliar as condições operacionais de temperatura (40, 50 e 60 °C), concentração da alimentação (3, 5, 7 e 10 µg L-1), recuperação de permeado (30, 50 e 70 %) e os efeitos da incrustação na retenção dos compostos fenólicos. A tecnologia foi eficiente com >90 % de remoção dos poluentes, mesmo para operações do processo com maiores temperaturas (60 °C) e recuperação do permeado (70 %). As variações da concentração da alimentação estudadas, não afetaram a qualidade do permeado gerado e a camada de incrustação formada favoreceu a concentração dos compostos fenólicos na solução de alimentação, praticamente, sem perda de massa no processo. Porém, com a incrustação houve um alto decaimento do fluxo de permeado em um curto período de tempo, sendo indicado a necessidade de estudar estratégias de pré-tratamento da água bruta e limpeza periódica do sistema. Experimentos, também foram realizados com o objetivo de avaliar o escalonamento da unidade de DMCD de bancada (0,0042 m2) para piloto (0,3 m2). Além disso, foi elaborado uma análise econômica considerando um sistema de DMCD para o tratamento de água móvel (5,5 m3 d-1), distribuído (11 m3 d-1) e centralizado (535.680 m3 d-1). Dentre os resultados alcançados, destaca-se que, o escalonamento do sistema não afetou a remoção dos fenóis. Ainda, foi evidenciado que a DMCD pode ser economicamente atraente para aplicações no tratamento de águas superficiais em larga escala, devido a redução da amortização dos altos custos de investimentos iniciais com a maior produção de água. Os custos operacionais dos sistemas DMCD foram comparados quanto ao uso de energia solar e de fontes elétricas convencionais. Os maiores valores foram relacionados ao emprego da energia solar devido à aquisição dos painéis fotovoltaicos, que aumentaram o valor da amortização. Algumas estratégias foram levantadas para diminuir os custos do investimento inicial, como o tratamento parcial da água (sistema menor), da amortização, trabalhando com a capacidade de processo >10.600 m³ d-1, e da energia gasta no trocador de calor, diminuindo a variação da temperatura entre as correntes da DMCD (ΔT) de 35 °C para 30 °C (OPEX: 0,50 US$ m-³ - 0,19 US$ m-³). Assim, a DMCD foi profundamente estudada para aplicação no tratamento de água e remoção de compostos fenólicos, pensando em um cenário moderno, robusto e mais seguro para o setor. Os desafios, também foram listados, deixando espaço para estudos futuros sobre como melhorar a eficiência energética do processo, aumentar o fluxo de permeado, reduzir custos e gerir o concentrado gerado. | The pollution of water sources by phenolic compounds is a problem in contemporary society associated with an expectation of high consumption of this resource. Direct contact membrane distillation (DCMD) has attracted attention to applications in water treatment and removal of micropollutants, due to its stability, modularity, and robustness. In addition, it can be associated with alternative energy sources such as renewable and waste heat. In this context, seeking solutions to established problems, this work studied the removal of phenolic compounds in surface water by DCMD. Therefore, a literature review (2000-2023) was conducted, which found the occurrence of more than 60 phenols in water sources in several countries at concentrations ranging from <0.065 to 179 M ng L-1. The risks to human health were estimated with the concentrations reported in the literature, showing concerning results for some phenols, such as 2-nitrophenol, 2,6-dichlorophenol, 3,4,5-Triclorophenol, 2,3,4,6-tetrachlorophenol, 2,4-dinitrophenol, 3-methylphenol, 2,4-dimethylphenol, 2,4,6-Triclorophenol, and pentachlorophenol. The importance of the water treatment sector in the removal of these micropollutants was emphasized, as well as the incorporation of more phenolic compounds in the drinking water guidelines for the protection of populations. The possibilities of phenol removal by membrane technologies were listed, highlighting the high removals of reverse osmosis as a mature technology with the lowest estimated ecological footprint, and membrane distillation as an emerging technology. Experiments were performed using bench scale DCMD to evaluate the operating conditions of temperature (40, 50, and 60 °C), feed concentration (3, 5, 7, and 10 µg L-1), permeate recovery (30, 50, and 70 %), and the fouling effects on the retention of phenolic compounds. The technology was efficient with >90 % removal of pollutants, even for process operations with higher temperatures (60 °C) and permeate recovery (70 %). The variations of the feed concentration studied, did not affect the quality of the permeate generated and the fouling layer formed favored the concentration of phenolic compounds in the feed solution, practically, without loss of mass in the process. However, with the fouling there was a high decay of the permeate flux in a short period, being indicated the need to study strategies of pre-treatment of raw water and periodic cleaning of the system. Experiments were also performed to evaluate the scale-up of the DCMD unit from bench (0.0042 m2) to pilot (0.3 m2). Furthermore, an economic analysis was developed considering mobile (5.5 m3 d-1), distributed (11 m3 d-1), and centralized (535,680 m3 d-1) DCMD water treatment systems. Among the results achieved, it is noteworthy that the system scale-up did not affect the removal of phenols. Also, it was evidenced that DCMD can be economically attractive for applications in surface water treatment on a large scale, due to the reduction of the amortization of the high initial investment costs with the higher water production. The operating costs of DCMD systems were compared for the use of solar energy and conventional electrical sources. The highest values were related to the use of solar energy due to the acquisition of photovoltaic panels, which increased the value of the amortization. Some strategies were raised to reduce the costs of the initial investment, such as the partial treatment of water (smaller system), amortization, working with a processing capacity >10,600 m³ d-1, and the energy spent on the heat exchanger, decreasing the temperature variation between the DCMD currents (ΔT) from 35 °C to 30 °C (OPEX: 0.50 US$ m-³ - 0.19 US$ m-³). Thus, DCMD was deeply studied for application in water treatment and removal of phenolic compounds, considering a modern, robust, and safer scenario for the sector. The challenges were also listed, leaving room for future studies on how to improve process energy efficiency, increase permeate flux, reduce costs, and manage the generated concentrate. | CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico | FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais | CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

[ES] En el contexto actual, la industria alimentaria emerge como el sector manufacturero predominante en la Unión Europea, contribuyendo con el 14,3% de los ingresos totales. España, con su extensa superficie de viñedos, se destaca como un actor significativo en este ámbito. A pesar de los desafíos climáticos, la producción vinícola en el período 2022 - 2023 experimentó un aumento con respecto a la temporada anterior, generando anualmente entre 2 y 3 millones de toneladas de residuos, siendo los orujos de uva el subproducto principal (62%). La gestión sostenible de estos residuos se ha vuelto esencial para avanzar hacia una economía circular y abordar los desafíos medioambientales mediante la contribución de los Objetivos de Desarrollo Sostenible (ODS) como parte de la Agenda 2030. La relevancia de los orujos de uva se encuentra en su elevado contenido de compuestos fenólicos, que poseen amplias propiedades bioactivas como la capacidad antioxidante. En línea con los principios de la Química Sostenible, se propone la extracción con agua subcrítica como una técnica innovadora para el fraccionamiento y valorización del orujo. Para ello, se estudió el proceso de extracción a diferentes temperaturas (120, 140 y 160 ºC), analizando los rendimientos, y los contenidos en fenoles y antocianos y capacidad antioxidante de los extractos y residuos de extracción, en comparación con los valores de la materia prima. Los mejores resultados se obtuvieron a 120 °C y 1,3 bar. Los extractos presentaron un rendimiento destacado de 61 g /100 g de sólidos de orujo, una riqueza fenólica de 4,1 g GAE/100 g de extracto y una capacidad antioxidante equiparable a la de antioxidantes típicos puros como el ácido ascórbico o el α-tocoferol. Adicionalmente, el residuo resultante de este proceso (38 g/100 g de sólidos de orujo) se presenta como un subproducto valioso, caracterizado por un alto contenido de fibras y un considerable contenido fenólico (10 g GAE/100 g de residuo) y alta capacidad antioxidante. Por tanto, el fraccionamiento del orujo con agua subcrítica a 120 ºC permitió la obtención de ingredientes de alto valor; uno soluble y otro rico en fibras insolubles, ambos con gran potencial para su aplicación en la industria alimentaria, farmacéutica o cosmética, subrayando la viabilidad y sostenibilidad del proceso sin utilización de solventes tóxicos. | [EN] In the current context, the food industry emerges as the predominant manufacturing sector in the European Union, contributing 14,3% of total revenues. Spain, with its extensive vineyard area, stands out as a significant contributor in this field. Despite climatic challenges, wine production in the period 2022-2023 experienced an increase compared to the previous season, generating between 2 and 3 million tonnes of waste annually, with grape marc being the main by-product (62%). Sustainable management of this waste has become essential to move towards a circular economy and address environmental challenges by contributing to the Sustainable Development Goals (SDGs) as part of the 2030 Agenda. The relevance of grape pomace lies in its high content of phenolic compounds, which possess broad bioactive properties such as antioxidant capacity. In line with the principles of Sustainable Chemistry, subcritical water extraction is proposed as an innovative technique for the fractionation and valorisation of grape pomace. To this end, the extraction process was studied at different temperatures (120, 140 and 160 ºC), analysing the yields, phenol and anthocyanin contents and antioxidant capacity of the extracts and extraction residues, in comparison with the values of the raw material. The best results were obtained at 120 °C and 1,3 bar. The extracts showed an outstanding yield of 61 g/100 g pomace solids, a phenolic richness of 4,1 g GAE/100 g extract and an antioxidant capacity comparable to that of typical pure antioxidants such as ascorbic acid or α-tocopherol. Additionally, the residue resulting from this process (38 g/100 g pomace solids) is presented as a valuable by-product, characterised by a high fibre content and a considerable phenolic content (10 g GAE/100 g residue) and high antioxidant capacity. Therefore, fractionation of the pomace with subcritical water at 120 ºC allowed for obtaining high value ingredients; one soluble and the other rich in insoluble fibres, both with great potential for application in the food, pharmaceutical or cosmetic industry, underlining the viability and sustainability of the process without the use of toxic solvents. | TFGM | Sáez Montesinos, AM. (2024). Aplicación de la extracción con agua subcrítica para la valoración del orujo de vinificación. Universitat Politècnica de València. http://hdl.handle.net/10251/203169

Frente al constante aumento de la temperatura a nivel global y al progresivo avance del cambio climático, se ha hecho cada vez más común en el mundo vitivinícola la producción de vinos con un nivel de grado alcohólico más elevado. Esto se debe a la constante alza en los niveles de azúcar en la uva, al momento de la cosecha, materia prima de la elaboración del vino. Este estudio buscó evidenciar los resultados de los parámetros químicos y sensoriales de dos tratamientos de adición de agua creciente al mosto de uva, con el fin de disminuir los sólidos solubles de éste, mediante una dilución y así obtener una menor graduación alcohólica en el posterior vino. Para la realización de este estudio, se utilizaron mostos de uva, provenientes de un cv. Chardonnay, del valle de Curicó. Se llevaron a cabo 2 tratamientos con la adición de 5% y 10% de agua, además del tratamiento control, el cual no tuvo adición de agua. Los resultados reflejaron una disminución el grado alcohólico en ambos tratamientos. Sin embargo, el tratamiento donde se añadió un 5% dio como resultado vinos con menores cambios en sus atributos sensoriales y componentes químicos, tales como, fenoles de bajo peso molecular, compuestos volátiles y polisacáridos. En cambio, en el tratamiento con un 10% de adición de agua se observaron como resultado vinos con una mayor disminución de su grado alcohólico (-12,4%). No obstante, se evidenció, una significativa alteración de sus atributos sensoriales, específicamente en los atributos de carácter gustativo como la untuosidad y persistencia, los vinos generados de este tratamiento presentaron menor complejidad y preferencia de parte los consumidores. Estos resultados indican la posibilidad de reducir el grado alcohólico en vinos mediante una adición controlada de agua en el mosto, no obstante, algunos atributos sensoriales y químicos podrían verse alterados levemente. Esta práctica podría ser una buena alternativa de adaptación frente al escenario climático que enfrenta la vitivinicultura hoy en día, siempre y cuando se tenga en cuenta el impacto que podría producir en el vino resultante. | Faced with the constant increase in global temperature and the progressive advance of climate change, the production of wines with a higher alcoholic level has become increasingly common in the wine world. This is due to the constant rise in sugar levels in grape at the time of harvest, raw material of wine processing. This study sought to demonstrate the results of the chemical and sensory parameters of two treatments of increasing water addition to the grape must, in order to decrease the soluble solids of it, by a dilution and thus obtain a lower alcoholic gradation in the subsequent wine. For this study, were used grape musts from a cv. Chardonnay, in the Curicó valley. Two treatments were carried out with the addition of 5% and 10% water, in addition to the control treatment, which had no addition of water. The results reflected a decrease in the alcohol level in both treatments. However, the treatment where 5% was added resulted in wines with lesser changes in their sensory attributes and chemical components, such as, low molecular weight phenols, volatile compounds and polysaccharides. In contrast, in the treatment with a 10% addition of water were observed as a result wines with a greater decrease in their alcoholic degree (-12.4%). however, a significant alteration of their sensory attributes was shown, specifically in the attributes of a tasty character such as unctuosity and persistence, the wines generated by this treatment presented less complexity and preference on the part of consumers. These results indicate the possibility of reducing the alcoholic degree in wines by controlled addition of water to the must, however, some sensory and chemical attributes may be slightly altered. This practice could be a good alternative to adapting to the climate scenario facing wine-growing today, provided that the impact it could have on the resulting wine is taken into account. | Versión original del autor

El salvado de trigo es un residuo valorizable debido a que presenta un alto contenido en compuestos fenólicos y una fracción proteica rica en albúminas, prolaminas y glutelinas. El objetivo del trabajo fue estudiar la recuperación de las fracciones polifenólica y proteica del salvado de trigo utilizando como agentes de extracción distintos biocatalizadores enzimáticos y diferentes mezclas etanol-agua, así como analizar el efecto de la temperatura y del contacto ultrasónico en su liberación a la fase extracto. Finalmente, se realizó un estudio comparativo de identificación y cuantificación de los principales tipos de compuestos polifenólicos extraídos y del perfil de aminoácidos de la fracción proteica recuperada en las diferentes condiciones de extracción utilizadas. | This final degree project shows the experimental results of the recovery of bioactive substances from wheat bran using enzyme biocatalysts and ethanol-water mixtures as extraction agents. Wheat bran (WB) was selected because it is an abundant by-product of wheat flour processing, containing 13-19% high quality proteins with a wide variety of biological functions and 4-8% polyphenolic compounds with antioxidant and anti-tumour activity. Ultrasound-assisted extraction and bath extraction were employed as the extraction techniques. The enzyme biocatalyst was cellulose and a binary mixture of xylanase (40%) and protease (60%). Ethanol-water solutions were mixtures from 0 wt.% to 100 wt.% ethanol. Different extraction tests were carried out in order to analyse the effect of extraction agent and extraction technique on the recovery degree of the polyphenolic and protein fractions from leaf WB, granulated WB and powdered WB. The extraction results were quite similar, with minor differences, for the three types of WB examined. A faster recovery of polyphenols was obtained by ultrasonic-assisted extraction, compared to bath extraction for all WB and extraction agents. The best recovery of the polyphenolic and protein fractions was obtained by using the xylanase-protease mixture. Gallic acid and ferulic acid have been identified as the main phenolic compounds in WB extracts, with the identification of vanillinic acid and syringic aldehyde in all extracts from powdered WB. In addition, the protein recovery was similar in the three WB types, with high proportion of essential amino acids. This amino acid results have confirmed the high food quality of recovered proteins. It can be concluded that the effect of cellulase enzyme and ethanol did not improve the recovery of the polyphenolic and protein fractions in either case. However, ethyl ferulate was the main polyphenolic compound in all ethanol-water WB extracts.

This study was carried out to examine the physiological traits, quality of calyx extract and seed oil content of roselle (Hibiscus sabdariffa L.) as affected by irrigation regimes and planting dates. The growth period from seed sowing to calyx harvesting was shortened as planting time was delayed. Stem diameter and plant height were decreased by drought stress or late planting, but calyx yield, total phenolic content, total anthocyanin content, vitamin C, and calyx water use efficiency increased under mild drought condition. In addition, antioxidant activity and calyx water use efficiency were significantly increased by late planting. It was suggested that an increase in calyx harvest index in delay in planting would be due to better photosynthesis activity and higher assimilate use efficiency because of the increase in sink capacity. Seed oil content decreased considerably due to drought stress and delay in planting date. These findings suggest that mild drought stress improves the quality and quantity of calyx and water use efficiency. | Este estudio se llevó a cabo para examinar los rasgos fisiológicos, la calidad del extracto de cáliz y el contenido de aceite de semillas de roselle (Hibiscus sabdariffa&nbsp;L.) afectado por regímenes de riego y fecha de siembra. El período de crecimiento desde la siembra de la semilla hasta la cosecha del cáliz se acortó debido a que se retrasó el tiempo de siembra. El diámetro del tallo y la altura de la planta disminuyeron por el estrés por sequía o la siembra tardía, pero el rendimiento del cáliz, el contenido fenólico total, el contenido total de antocianinas, la vitamina C y la eficiencia del uso del agua del cáliz aumentaron en condiciones de sequía leve. Además, la actividad antioxidante y la eficiencia del uso del agua del cáliz aumentaron significativamente en la siembra tardía. Se sugirió que el aumento del índice de cosecha del cáliz en la demora en la siembra se debería a una mejor actividad de fotosíntesis y una mayor eficiencia en el uso de asimilación debido al aumento de la capacidad de hundimiento. El contenido de aceite de las semillas disminuyó considerablemente debido al estrés por sequía y al retraso en la fecha de siembra. Estos hallazgos sugieren que el estrés por sequía leve mejora la calidad y cantidad del cáliz y la eficiencia del uso del agua.