20 resultados para olive oil

em Universidad Politécnica de Madrid


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This paper evaluates the water footprint of Spanish olives and olive oil over the period 1997-2008. In particular, it analyses the three colour components of the water footprint: green (rainwater stored in the soil), blue (surface and groundwater) and grey (freshwater required to assimilate load of pollutants). Apparent water productivity and virtual water embedded in olive oil exports have also been studied. Results show more than 99.5% of the water footprint of one liter of bottled olive oil is related to the olive production, whereas less than 0.5% is due to the other components such as bottle, cap and label. Over the studied period, the green water footprint in absolute terms of Spanish olive oil production represents about 72% in rainfed systems and just 12% in irrigated olive orchards. Blue and grey water footprints represent 6% and 10% of the national water footprint, respectively. It is shown that olive production is concentrated in regions with the smallest water footprint per unit of product. However, the increase of groundwater consumption in the main olive producing region (Andalusia), from 98 to 378 Mm3 between 1997 and 2008, has added significant pressure in the upstream Guadalquivir basin. This raises questions about the sustainability of irrigated olive orchards for export from the region. Finally, the virtual water related to olive oil exports illustrate the importance of green water footprint of rainfed olives amounting to about 77% of the total virtual water exports.

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The effect of location of fruit in canopies of hedgerow olive trees (Olea europaea L., cv. ‘Arbequina’) on quality of virgin oil was tested by analyzing oils extracted from different height layers and faces of 9 olive hedgerows (6 North-South oriented and 3 East-West). Although sensory attributes were not different other oil quality parameters may be significantly modified by fruit position. In some hedgerows, oils extracted from fruits harvested from higher layers exhibited significantly higher stability against oxidation, along with higher palmitic acid, linoleic acid and phenol contents, but lower oleic acid content. Oils extracted from fruits harvested from East and North facing hedgerows oriented North-South and East-West, respectively, exhibited higher oleic contents and lower saturated and polyunsaturated fatty acid contents. The mean phenol content of oils extracted from fruits from a North-South oriented hedgerow was significantly greater from one of the East-West oriented hedgerows. These findings may be relevant for the design of future olive hedgerows destined for olive oil production.

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En este trabajo se recogieron muestras de aceituna procedente de distintas alturas de setos cultivados en diferentes condiciones para evaluar el efecto en la calidad del aceite.

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The effect of location of fruit in canopies of hedgerow olive trees (Olea europaea L., cv. ‘Arbequina’) on quality of virgin oil was tested by analyzing oils extracted from different height layers and faces of nine olive hedgerows (6 North–South oriented and 3 East– West). Although sensory attributes were not different, other oil quality parameters may be significantly modified by fruit position. Oils extracted from fruits harvested from higher layers exhibited significantly higher stability against oxidation, along with higher palmitic acid, linoleic acid and phenol contents, but lower oleic acid content. Oils extracted from fruits harvested from East and North facing hedgerows oriented North–South and East–West, respectively, exhibited higher oleic contents and lower saturated and polyunsaturated fatty acid contents. The mean phenol content of oils extracted from fruits from a North–South oriented hedgerow was significantly greater from one of the East–West oriented hedgerows. These findings may be relevant for the design of future olive hedgerows destined for olive oil production.

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Developing products having a high nutritional value and good storage stability during freezing is a challenge. Inulin (I) and extra virgin olive oil (EVOO) have interesting functional properties. The e?ect of the addition of I and EVOO blends at di?erent I:EVOO ratios (0:0, 0:60, 15:45, 30:30, 45:15, 60:0, 30:45 and 45:30) on the rheological, physical, sensory and structural properties of fresh and frozen ? thawed mashed potatoes formulated without and with added cryoprotectants was analysed and compared. Addition of I and EVOO (either alone or blended) reduced apparent viscosity and pseudoplasticity producing softer systems, indicating that both ingredients behave as soft ?llers. Samples with added I at the higher concentrations )1 (?45 g kg ) showed lower ?ow index and consistency, which is related to formation of smaller I particles; microphotographs indicated that gelling properties of I depended mostly upon processing. Frozen ? thawed samples were judged more acceptable and creamier than their fresh counterparts.

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The effect of adding different ratios of inulin and extra virgin olive oil blends, formulated without (MPA) and with cryoprotectants (MPB), on texture properties of fresh mashed potatoes and frozen/thawed mashed potatoes was studied. Inulin and extra virgin olive oil behaved like soft ?llers, but inulin was associated with increased?brousness and extra virgin olive oil with increased creaminess. In the total dataset and frozen mashed potatoes, frozen/thawed mashed potatoes, and MPA subgroups, component 1 was a contrast between mechanical and surface textural attributes, whereas in MPB samples component 1 was determined by geometrical attributes. Addition of inulin at 30 g/kg and extra virgin olive oil at 45 g/kg is recommended.

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The present work is a preliminary study to settle the optimum experimental conditions and data processing for accomplishing the strategies established by the Action Plan for the EU olive oil sector. The objectives of the work were: a) to monitor the evolution of extra virgin olive oil exposed to indirect solar light in transparent glass bottles during four months; b) to identify spectral differences between edible and lampant virgin olive oil by applying high resolution Nuclear Magnetic Resonance (HR-NMR) Spectroscopy. Pr esent study could contribute to determine the date of minimum storage, their optimum conditions, and to properly characterize olive oil.

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BACKGROUND: The effect of regulated deficit irrigation (RDI) on the phytoprostane (PhytoP) content in extra virgin olive (Olea europaea L., cv. Cornicabra) oil (EVOO) was studied. During the 2012 and 2013 seasons, T0 plants were irrigated at 100% ETc, while T1 and T2 plants were irrigated avoiding water deficit during phases I and III of fruit growth and saving water during the non-critical phenological period of pit hardening (phase II), developing amore severewater deficit in T2 plants. In 2013, a fourth treatment (T3) was also performed, which was similar to T2 except that water saving was from the beginning of phase II to 15 days after the end of phase II. RESULTS: 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, 9-epi-9-D1t-PhytoP, 9-D1t-PhytoP, 16-B1-PhytoP and 9-L1-PhytoP were present in Cornicabra EVOO, and their contents increased in the EVOO fromRDI plants. CONCLUSION: Deficit irrigation during pit hardening or for a further period of 2 weeks thereafter to increase irrigation water saving is clearly critical for EVOO composition because of the enhancement of free PhytoPs, which have potential beneficial effects on human health. The response of individual free PhytoPs to changes in plant water status was not as perceptible as expected, preventing their use as biomarkers of water stress.

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For the energy valorization of alperujo, residue of the olive oil two phases extraction process, it is necessary to perform a drying process to reduce moisture content from over 60% to less than 10%. In order to reduce primary energy consumption and get an economic return, usually in this kind of drying facilities Gas Turbine CHP is used as a heat source. There have been recently in Spain some fires in this kind of GT-CHP facilities, which have caused high material losses. In some of these fires it has been suggested that the fire was caused by the output of incandescent alperujo in the flue gasesof the drying system. Therefore, the aim of this study is to determine experimentally and analytically under which operational conditions a process of alperujo self-ignition in the drying process can begin, and determine the actual fire hazard in this type of TG-CHP system. For analytical study, the temperature and initial composition of the combustion gases of the Gas Turbine at the entrance of the drying process was calculated and the gas equilibrium conditions reached in contact with the biomass were calculated and, therefore, the temperature of the biomass during the drying process. Moreover, the layer and dust ignition temperature of alperujo has been experimentally determined, according to EN 50281-2-1: 2000. With these results, the operating conditions of the drying process, in which there are real risk of auto-ignition of alperujo have been established.Para la valorización energética del alperujo, residuo del proceso de extracción en dos fases del aceite de oliva, es necesario realizar un proceso de secado para reducir su contenido de humedad de más del 60% al 10% m/m en b.h. Con el fin de reducir el consumo de energía primaria y obtener una rentabilidad económica, normalmente en este tipo de instalaciones de secado se usa la cogeneración con turbina de gas (TG) como fuente de calor. En España en los últimos años han ocurrido algunos casos de incendio en este tipo de instalaciones de cogeneración, que han supuesto pérdidas materiales muy elevadas. Por esta razón, el objetivo de este trabajo es determinar analítica y experimentalmente las condiciones operativas del secadero bajo las cuales podría comenzar un proceso de autoinflamación del alperujo y determinar el riesgo real de incendio en este tipo de instalaciones. Para el estudio analítico, se ha planteado y validado el modelo matemático que permite calcular la temperatura y la composición de los gases de combustión a la entrada y a la salida del secadero, en función de las curvas características de la TG, de las condiciones atmosféricas, del caudal y del grado de humedad de la biomasa tratada. El modelo permite además calcular la temperatura de bulbo húmedo, que es la máxima temperatura que podría alcanzar la biomasa durante el proceso de secado y determinar la cantidad de biomasa que se puede secar completamente en función del caudal y de las condiciones de entrada de los gases de combustión. Con estos resultados y la temperatura mínima de autoinflamación del alperujo determinada experimentalmente siguiendo la norma EN 50281- 2-1:2000, se demuestra que en un proceso de secado de alperujo en condiciones normales de operación no existe riesgo de autoencendido que pueda dar origen a un incendio.

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El presente trabajo trata sobre la evolución de las construcciones rurales en una de las mayores regiones españolas, La Mancha. Se analizan básicamente tres puntos: a) Los materiales y sistemas de ejecución. b) Los diseños. c) Como síntesis de las dos anteriores. Las tipologías. Los materiales se estudian por periodos de tiempo, y los diseños por tipo de edificación agraria. Se ha deducido que los edificios más interesantes por su evolución son las bodegas, harineras y almazaras. SUMMARY The present work deals on evolution suffered by rural buildings in one of the larger spanish región, La Mancha. Three different points have been analysed: a) Materials and carrying out systems. b) Designs. c) As a synthesis of the both above, typologys. Materials have been studied by periods of time, designs by type of rural buildings. It has been thought the most interesting buildings, in terms of evolution, are wineries, flour milis and olive-oil milis.

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Sustainability is an adjective used to characterize agriculture according to the degree of fulfillment of goals. Those goals are related to agro-ecological, environmental and socio-economic dimensions. Sustainability is a dynamic and temporal character. In absolute terms there is not an ending value because it changes as its dimensions make it. Spain is one of the main agricultural countries of the European Union both in terms of crop land and value of productions. The object of this study is to present a methodology of sustainability account to be incorporated into national statistical and to assess their performance in the course of the years. For that reason the data sources used have been the statistics of the Department of Agriculture and from others database. We presented a set of indicators of sustainability and its evaluation in a time series of at least 30 years. The trend analysis offers the evolution of the numerical values of the indicators in terms of efficiency, physical units used for a unit of product or its value in euros. The analyzed crops have been: wheat, barley, maize, sunflower, sugar beet, wine grape, olive oil, citrus, melon and tomato. Physical indicators were: land, water, energy, erosion, soil organic matter, and carbon balance; socio-economic indicators were: agricultural final production, prices, income, employment and use of fertilizers. In general, all crops increased their productive efficiency, higher in irrigated than on dry land. Spanish agricultural carbon sequestration capacity has multiplied by five in the last seventy years, as a result of the increase in the productivity of crops, in terms of total biomass and the modification of the soil management techniques. Livestock sector presents data of pork, broilers and laying hen. Those showed an improvement in efficiency and economic indicators. Overall we can say that Spanish agriculture and livestock subsector have a tendency towards sustainability, being its main threats extreme meteorological factors and the instability of todays markets.

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El interés creciente en encontrar alimentos precocinados congelados que se asemejen a productos naturales, capaces de superar un procesado con el menor daño, ha generado un aumento en el estudio de nuevos productos en este campo de la investigación. Las características de cada matriz alimentaria, la composición y estructura de los ingredientes, así como el efecto de las interacciones entre ellos, modifica la textura, estructura y las propiedades físicas y sensoriales del alimento, así como su aceptación por el consumidor. En este contexto, la investigación realizada en esta tesis doctoral se ha llevado a cabo en puré de patata considerado como una matriz alimentaria semisólida y se ha centrado en analizar los efectos de la concentración y modificación de la composición en las propiedades reológicas y de textura, en las propiedades físico-químicas y estructurales, así como en los atributos sensoriales de los purés de patata cuando a estos se le añaden diferentes ingredientes funcionales como fibra de guisante, inulina, aceite de oliva, aislado de proteína de soja, ácidos grasos omega 3 y/o sus mezclas. Para ello, se han realizado cuatro estudios donde se determinan las propiedades reológicas mediante ensayos dinámicos oscilatorios y en estado estacionario, los parámetros instrumentales de textura mediante ensayos de extrusión inversa y de penetración cónica, además de los cambios estructurales a través de cromatografía iónica con detector de pulsos amperométrico, cromatografía de gases con detector de ionización de llama y microscopía electrónica de barrido. Conjuntamente, se han evaluado los atributos sensoriales de los diferentes purés generando los descriptores que mejor definen la calidad sensorial del producto, utilizando un panel de jueces entrenados y valorándose la aceptación global de los nuevos productos mediante un panel de consumidores. En un primer estudio, el puré de patata natural congelado elaborado con crioprotectores se enriqueció con fibra dietética insoluble (fibra de guisante), fibra dietética soluble (inulina) y sus mezclas. La fibra de guisante influyó significativa y negativamente en la textura del puré de patata, percibiéndose en el producto un incremento de la dureza y de la arenosidad, mientras que la inulina produjo un ablandamiento del sistema. En un segundo estudio, el puré de patata natural fresco y congelado/descongelado elaborado con y sin crioprotectores, se enriqueció con fibra dietética soluble (inulina), aceite de oliva virgen extra y sus mezclas. La adición de estos dos ingredientes generó un ablandamiento de la matriz del sistema, produciéndose, sin embargo, un efecto sinérgico entre ambos ingredientes funcionales. La inulina tuvo un efecto más significativo en la viscosidad aparente del producto, mientras que el aceite de oliva virgen extra afectó más significativamente a la pseudoplasticidad, al índice de consistencia y a la viscosidad plástica del mismo. El proceso de congelación y descongelación utilizado favoreció la reducción del tamaño de las partículas de inulina haciéndolas imperceptibles al paladar, obteniéndose productos más cremosos y con mayor aceptabilidad global que sus homólogos frescos. En un tercer estudio, el puré de patata natural fresco y congelado/descongelado elaborado con crioprotectores se enriqueció con mezclas de fibra dietética soluble (inulina) y aislado de proteína de soja. Los resultados demostraron que el ciclo de congelación y descongelación realizado no afecta el grado de polimerización de la inulina. La estructura química de la inulina tampoco se vio afectada por la incorporación de la soja. El proceso de congelación/descongelación, así como la adición de concentraciones altas de inulina y bajas de aislado de proteína de soja, favorecen la disminución de la contribución de la componente viscosa en las propiedades viscoelásticas del puré de patata. La cremosidad fue el único atributo sensorial que presentó una correlación lineal significativa entre las puntuaciones otorgadas por panelistas entrenados y no entrenados. Por último, se elaboró un puré de patata natural fresco y congelado/descongelado optimizado con crioprotectores y enriquecido con la suma de ácido docosahexaenoico (DHA, C22:6 n-3) y ácido eicosapentaenoico (EPA, C20:5 n-3) y con ácido α-linolénico (ALA, C18:3 n-3) microencapsulados. El ciclo de congelación y descongelación no afectó al perfil de ácidos grasos del puré de patata. La adición de omega 3 procedente de aceites de lino y pescado microencapsulados mejora los indicadores nutricionales que definen la calidad de la grasa, obteniéndose un producto más saludable. ABSTRACT The growing interest in finding frozen precooked products that are like a natural product and capable of withstanding initial processing with minimum damage and remaining stable during preservation and reheating prior to consumption has generated an increase in studies of new products in this field of research. The characteristics of each food matrix, the composition and structure of the ingredients and the effect of interactions between them alter the texture, structure and physical and sensory properties of the food product and its acceptance by the consumer. In this context, the research conducted in this doctoral thesis was carried out on mashed potato, considered as a semi-solid food matrix, and focused on analysing the effects of concentration and modification of the composition of the mashed potato matrix on the rheological and textural properties, physicochemical and structural properties and sensory attributes of mashed potato when various functional ingredients are added to it, such as pea fibre, inulin, olive oil, soy protein isolate, omega 3 fatty acids and/or mixtures of these ingredients. Four studies were conducted for this purpose. Rheological properties were determined by oscillatory dynamic tests and stationary state tests, and instrumental texture parameters by backward extrusion and cone penetration tests. Structural changes were studied by ion chromatography with pulsed amperometric detector, gas chromatography with flame ionisation detector and scanning electron microscopy. The sensory attributes of the various mashed potato mixtures were evaluated by generating the descriptors that best defined the sensory quality of the products and using a panel of trained judges, and overall acceptance of the new products was evaluated by a panel of consumers. In the first study, frozen natural mashed potato incorporating cryoprotectants was enriched with insoluble dietary fibre (pea fibre), soluble dietary fibre (inulin) and mixtures of the two. Pea fibre had a significant negative influence on the texture of the mashed potato, producing an increase in hardness and granularity, whereas inulin produced a softening of the system. In the second study, fresh and frozen/thawed natural mashed potato prepared with and without cryoprotectants was enriched with soluble dietary fibre (inulin), extra virgin olive oil and mixtures of the two. The addition of these two ingredients generated softening of the matrix of the system, but a synergic effect between the two functional ingredients was produced. Inulin had a more significant effect on the apparent viscosity of the product, whereas extra virgin olive oil had a more significant effect on its pseudoplasticity, consistency index and plastic viscosity. The freezing and thawing process that was used contributed to a reduction in the size of the inulin particles, making them imperceptible to the palate and producing creamier products with greater overall acceptability than their fresh equivalents. In the third study, the fresh and frozen/thawed natural mashed potato incorporating cryoprotectants was enriched with mixtures of soluble dietary fibre (inulin) and soy protein isolate. The results showed that the freezing and thawing process that was performed did not affect the degree of polymerisation of the inulin. The chemical structure of the inulin was also not affected by the incorporation of soy. The freezing and thawing process and the addition of high concentrations of inulin and low concentrations of soy protein isolate favoured a decrease in the contribution of the viscous component to the viscoelastic properties of the mashed potato. Creaminess was the only sensory attribute that presented a significant linear correlation between the scores given by trained and untrained panellists. Lastly, fresh and frozen/thawed natural mashed potato optimised with cryoprotectants was prepared and enriched with the sum of docosahexaenoic acid (DHA, C22:6 n-3) and eicosapentaenoic acid (EPA, C20:5 n-3) and with α-linolenic acid (ALA, C18:3 n-3), microencapsulated. The freezing and thawing process did not affect the fatty acid profile of the mashed potato. The addition of omega 3 obtained from microencapsulated linseed and fish oils improved the nutritional indicators that define the quality of the fat, producing a healthier product.

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Una gestión más eficiente y equitativa del agua a escala de cuenca no se puede centrar exclusivamente en el recurso hídrico en sí, sino también en otras políticas y disciplinas científicas. Existe un consenso creciente de que, además de la consideración de las cambiantes condiciones climáticas, es necesaria una integración de ámbitos de investigación tales como la agronomía, planificación del territorio y ciencias políticas y económicas a fin de satisfacer de manera sostenible las demandas de agua por parte de la sociedad y del medio natural. La Política Agrícola Común (PAC) es el principal motor de cambio en las tendencias de paisajes rurales y sistemas agrícolas, pero el deterioro del medio ambiente es ahora una de las principales preocupaciones. Uno de los cambios más relevantes se ha producido con la expansión e intensificación del olivar en España, principalmente con nuevas zonas de regadío o la conversión de olivares de secano a sistemas en regadío. Por otra parte, el cambio de las condiciones climáticas podría ejercer un papel importante en las tendencias negativas de las aportaciones a los ríos, pero no queda claro el papel que podrían estar jugando los cambios de uso de suelo y cobertura vegetal sobre las tendencias negativas de caudal observadas. Esta tesis tiene como objetivo mejorar el conocimiento de los efectos de la producción agrícola, política agraria y cambios de uso de suelo y cobertura vegetal sobre las condiciones de calidad del agua, respuesta hidrológica y apropiación del agua por parte de la sociedad. En primer lugar, el estudio determina las tendencias existentes de nitratos y sólidos en suspensión en las aguas superficiales de la cuenca del río Guadalquivir durante el periodo de 1998 a 2009. Desde una perspectiva de política agraria, la investigación trata de evaluar mediante un análisis de datos de panel las principales variables, incluyendo la reforma de la PAC de 2003, que están teniendo una influencia en ambos indicadores de calidad. En segundo lugar, la apropiación del agua y el nivel de contaminación por nitratos debido a la producción del aceite de oliva en España se determinan con una evaluación de la huella hídrica (HH), teniendo en cuenta una variabilidad espacial y temporal a largo de las provincias españolas y entre 1997 y 2008. Por último, la tesis analiza los efectos de los cambios de uso de suelo y cobertura vegetal sobre las tendencias negativas observadas en la zona alta del Turia, cabecera de la cuenca del río Júcar, durante el periodo 1973-2008 mediante una modelización ecohidrológica. En la cuenca del Guadalquivir cerca del 20% de las estaciones de monitoreo muestran tendencias significativas, lineales o cuadráticas, para cada indicador de calidad de agua. La mayoría de las tendencias significativas en nitratos están aumentando, y la mayoría de tendencias cuadráticas muestran un patrón en forma de U. Los modelos de regresión de datos de panel muestran que las variables más importantes que empeoran ambos indicadores de calidad del agua son la intensificación de biomasa y las exportaciones de ambos indicadores de calidad procedentes de aguas arriba. En regiones en las que el abandono agrícola y/o desintensificación han tenido lugar han mejorado las condiciones de calidad del agua. Para los nitratos, el desacoplamiento de las subvenciones a la agricultura y la reducción de la cuantía de las subvenciones a tierras de regadío subyacen en la reducción observada de la concentración de nitratos. Las medidas de modernización de regadíos y el establecimiento de zonas vulnerables a nitratos reducen la concentración en subcuencas que muestran una tendencia creciente de nitratos. Sin embargo, el efecto de las exportaciones de nitratos procedente de aguas arriba, la intensificación de la biomasa y los precios de los cultivos presentan un mayor peso, explicando la tendencia creciente observada de nitratos. Para los sólidos en suspensión, no queda de forma evidente si el proceso de desacoplamiento ha influido negativa o positivamente. Sin embargo, los mayores valores de las ayudas agrarias aún ligadas a la producción, en particular en zonas de regadío, conllevan un aumento de las tasas de erosión. Aunque la cuenca del Guadalquivir ha aumentado la producción agrícola y la eficiencia del uso del agua, el problema de las altas tasas de erosión aún no ha sido mitigado adecuadamente. El estudio de la huella hídrica (HH) revela que en 1 L de aceite de oliva español más del 99,5% de la HH está relacionado con la producción de la aceituna, mientras que menos del 0,5% se debe a otros componentes, es decir, a la botella, tapón y etiqueta. Durante el período estudiado, la HH verde en secano y en regadío representa alrededor del 72% y 12%, respectivamente, del total de la HH. Las HHs azul y gris representan 6% y 10%, respectivamente. La producción de aceitunas se concentra en regiones con una HH menor por unidad de producto. La producción de aceite de oliva ha aumentado su productividad del agua durante 1997-2008, incentivado por los crecientes precios del aceite, como también lo ha hecho la cantidad de exportaciones de agua virtual. De hecho, las mayores zonas productoras presentan una eficiencia alta del uso y de productividad del agua, así como un menor potencial de contaminación por nitratos. Pero en estas zonas se ve a la vez reflejado un aumento de presión sobre los recursos hídricos locales. El aumento de extracciones de agua subterránea relacionadas con las exportaciones de aceite de oliva podría añadir una mayor presión a la ya estresada cuenca del Guadalquivir, mostrando la necesidad de equilibrar las fuerzas del mercado con los recursos locales disponibles. Los cambios de uso de suelo y cobertura vegetal juegan un papel importante en el balance del agua de la cuenca alta del Turia, pero no son el principal motor que sustenta la reducción observada de caudal. El aumento de la temperatura es el principal factor que explica las mayores tasas de evapotranspiración y la reducción de caudales. Sin embargo, los cambios de uso de suelo y el cambio climático han tenido un efecto compensatorio en la respuesta hidrológica. Por un lado, el caudal se ha visto afectado negativamente por el aumento de la temperatura, mientras que los cambios de uso de suelo y cobertura vegetal han compensado positivamente con una reducción de las tasas de evapotranspiración, gracias a los procesos de disminución de la densidad de matorral y de degradación forestal. El estudio proporciona una visión que fortalece la interdisciplinariedad entre la planificación hidrológica y territorial, destacando la necesidad de incluir las implicaciones de los cambios de uso de suelo y cobertura vegetal en futuros planes hidrológicos. Estos hallazgos son valiosos para la gestión de la cuenca del río Turia, y el enfoque empleado es útil para la determinación del peso de los cambios de uso de suelo y cobertura vegetal en la respuesta hidrológica en otras regiones. ABSTRACT Achieving a more efficient and equitable water management at catchment scale does not only rely on the water resource itself, but also on other policies and scientific knowledge. There is a growing consensus that, in addition to consideration of changing climate conditions, integration with research areas such as agronomy, land use planning and economics and political science is required to meet sustainably the societal and environmental water demands. The Common Agricultural Policy (CAP) is a main driver for trends in rural landscapes and agricultural systems, but environmental deterioration is now a principal concern. One of the most relevant changes has occurred with the expansion and intensification of olive orchards in Spain, taking place mainly with new irrigated areas or with the conversion from rainfed to irrigated systems. Moreover, changing climate conditions might exert a major role on water yield trends, but it remains unclear the role that ongoing land use and land cover changes (LULCC) might have on observed river flow trends. This thesis aims to improve the understanding of the effects of agricultural production, policies and LULCC on water quality conditions, hydrological response and human water appropriation. Firstly, the study determines the existing trends for nitrates and suspended solids in the Guadalquivir river basin’s surface waters (south Spain) during the period from 1998 to 2009. From a policy perspective, the research tries to assess with panel data analysis the main drivers, including the 2003 CAP reform, which are having an influence on both water quality indicators. Secondly, water appropriation and nitrate pollution level originating from the production of olive oil in Spain is determined with a water footprint (WF) assessment, considering a spatial temporal variability across the Spanish provinces and from 1997 to 2008 years. Finally, the thesis analyzes the effects of the LULCC on the observed negative trends over the period 1973-2008 in the Upper Turia basin, headwaters of the Júcar river demarcation (east Spain), with ecohydrological modeling. In the Guadalquivir river basin about 20% of monitoring stations show significant trends, linear or quadratic, for each water quality indicator. Most significant trends of nitrates are augmenting than decreasing, and most significant quadratic terms of both indicators exhibit U-shaped patterns. The panel data models show that the most important drivers that are worsening nitrates and suspended solids in the basin are biomass intensification and exports of both water quality indicators from upland regions. In regions that agricultural abandonment and/or de-intensification have taken place the water quality conditions have improved. For nitrates, the decoupling of agricultural subsidies and the reduction of the amount of subsidies to irrigated land underlie the observed reduction of nitrates concentration. Measures of irrigation modernization and establishment of vulnerable zones to nitrates ameliorate the concentration of nitrates in subbasins showing an increasing trend. However, the effect of nitrates load from upland areas, intensification of biomass and crop prices present a greater weight leading to the final increasing trend in this subbasins group, where annual crops dominate. For suspended solids, there is no clear evidence that decoupling process have influenced negatively or positively. Nevertheless, greater values of subsidies still linked to production, particularly in irrigated regions, lead to increasing erosion rates. Although agricultural production has augmented in the basin and water efficiency in the agricultural sector has improved, the issue of high erosion rates has not yet been properly faced. The water footprint (WF) assessment reveals that for 1 L Spanish olive oil more than 99.5% of the WF is related to the olive fruit production, whereas less than 0.5% is due to other components i.e. bottle, cap and label. Over the studied period, the green WF in rainfed and irrigated systems represents about 72% and 12%, respectively, of the total WF. Blue and grey WFs represent 6% and 10%, respectively. The olive production is concentrated in regions with the smallest WF per unit of product. The olive oil production has increased its apparent water productivity from 1997 to 2008 incentivized by growing trade prices, but also did the amount of virtual water exports. In fact, the largest producing areas present high water use efficiency per product and apparent water productivity as well as less nitrates pollution potential, but this enhances the pressure on the available water resources. Increasing groundwater abstractions related to olive oil exports may add further pressure to the already stressed Guadalquivir basin. This shows the need to balance the market forces with the available local resources. Concerning the effects of LULCC on the Upper Turia basin’s streamflow, LULCC play a significant role on the water balance, but it is not the main driver underpinning the observed reduction on Turia's streamflow. Increasing mean temperature is the main factor supporting larger evapotranspiration rates and streamflow reduction. In fact, LULCC and climate change have had an offsetting effect on the streamflow generation during the study period. While streamflow has been negatively affected by increasing temperature, ongoing LULCC have positively compensated with reduced evapotranspiration rates, thanks to mainly shrubland clearing and forest degradation processes. The research provides insight for strengthening the interdisciplinarity between hydrological and spatial planning, highlighting the need to include the implications of LULCC in future hydrological plans. These findings are valuable for the management of the Turia river basin, as well as a useful approach for the determination of the weight of LULCC on the hydrological response in other regions.

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La implementación de indicaciones geográficas, generan distintos efectos socio-económicos, tecnológicos y ambientales, no sólo a nivel de los productores directamente involucrados, sino también en el marco del sistema agroalimentario local (SIAL). Entre estos últimos, se destaca la organización colectiva de los productores y el desarrollo de una gobernanza, a partir del conjunto de actividades desarrolladas por el Consejo Regulador (CR), en torno al control de calidad y la promoción del producto. El concepto de gobernanza territorial implica llevar a cabo procesos de organización colectiva en red en los que tienen lugar procesos de coordinación multi-nivel entre los agentes, las empresas y las instituciones locales, en un contexto de asimetría en la información y de la existencia de numerosos decisores. El objetivo de esta Tesis Doctoral es realizar un aporte metodológico para el estudio de la gobernanza territorial en sistemas agroalimentarios localizados, a partir de la construcción de indicadores (de calidad, innovación, efectos económicos y prácticas ambientales) y el análisis de las redes de colaboración en materia de difusión del conocimiento e innovaciones técnicas, organizativas y comerciales en la Comarca de Sierra Mágina. Para responder el objetivo se aplica análisis de redes sociales y se construyen indicadores sintéticos para valorizar los efectos. Se realizan encuestas a la totalidad de almazaras presentes en la Comarca de Sierra Mágina, tanto a las que poseen el signo de calidad como a las que no cuentan con dicha marca territorial y entrevistas a testigos privilegiados. En las mismas se consulta sobre las actividades y proyectos que realizan en forma conjunta con otras almazaras e instituciones, así como los actores o referentes a quiénes consultan en temas relacionados con la calidad en la producción olivícola y la obtención de aceite, así como aquellos actores a quienes consultan en aspectos referidos a la Comercialización y gestión. A partir de la información recabada, se obtienen cuatro indicadores sintéticos de efectos de la implantación de una DOP en las almazaras adheridas, referidos a la adopción de innovaciones productivas y organizativas, a la calidad en producto y procesos, a las rentas de diferenciación y a las prácticas ambientales. Asimismo se generan las matrices bi-narias y valuadas para las redes de colaboración en la difusión del conocimiento y se calculan los indicadores particulares. Esto nos permite estudiar las características de las redes que se generan (tamaño, conectividad), el papel del CR en la gobernanza territorial y de otras instituciones del medio, así como identificar actores centrales y grupos en el proceso de difusión de conocimientos. Los resultados muestran que los SIAL pueden beneficiarse de la organización interprofesional y de cooperación interinstitucional a escala local que se producen tras la implantación de una DOP. Se desarrolla un proceso de articulación y un fuerte intercambio de conocimientos entre actores ligados al propio proceso de control de la calidad diferencial. Pero, junto con ello, se desarrollan actividades de formación y de promoción del patrimonio comarcal y se consolidan redes locales de innovación y colaboración mutua en distintas actividades, tanto entre actores de la propia cadena de producción, como entre éstos y las instituciones del medio. Estas actividades, junto con la presencia de un entramado institucional denso, permiten el desarrollo de una gobernanza territorial alrededor del sistema agroalimentario del aceite de oliva. ABSTRACT The implementation of geographical indications has different socio-economic, technological and environmental effects not only for the producers involved but also for the local agro food system (LAFS). Among the latter, we can highlight the collective organization of producers and the development of territorial governance through a series of tasks developed by the Regulatory Board (RB) as regards quality control and product marketing. The concept of territorial governance involves processes of collective organization in networks, where processes of multi-level coordination among agents, enterprises and local institutions take place within a context of asymmetry of information and numerous decision makers. The objective of this Doctoral Thesis is to contribute with methodological tools for the study of territorial governance in local agro food systems by constructing indicators (of quality, innovation, economic effects and environmental practices) and by analyzing networks of collaboration in terms of dissemination of technical, organizational and commercial innovation and knowledge in Comarca de Sierra Mágina. To achieve that objective, social network analysis is applied and synthetic indicators are elaborated to valorize the effects. Interviews to key actors and surveys to every oil mill in Comarca de Sierra Mágina are carried out, not only in those oil mills that host a label of quality but also in the ones that do not hold it. These interviews inquire about tasks and projects performed together with other oil mills and institutions and about actors or referents consulted in topics related to quality in olive production and oil extraction as well as in management and marketing. From all the information collected, four synthetic indicators of the effects of establishing Protected Designations of Origen (PDOs) in the associate oil mills are obtained, in terms of adoption of productive and organizational innovations, process and product quality, income differentiation and environmental practices. In the same way, binary and valorized matrixes are generated for those networks collaborating in the dissemination of knowledge and specific indicators are calculated. This allows to study networks (size, connectivity), the role of RB in territorial governance and other institutions involved and to identify main actors and groups in the process of knowledge dissemination. The results show that the LAFS can benefit from inter-professional organizations and inter- institutional cooperation at local levels by implementing PDOs. A process of articulation and strong exchange of knowledge is developed among those actors involved in controlling differential quality. But, at the same time, activities for the formation and promotion of the “comarca” patrimony are developed and local networks of innovation and mutual collaboration are built for different activities, not only among actors in the production process itself, but between these actors and local institutions as well. These tasks, together with the existence of a dense spatial entrepreneurial network, allow the development of territorial governance on the olive oil agro food system.

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Enhancing the quality of beef meat is an important goal in terms of improving both the nutritional value for the consumer and the commercial value for producers. The aim of this work was to study the effects of different vegetable oil supplements on growth performance, carcass quality and meat quality in beef steers reared under intensive conditions. A total of 240 Blonde D? Aquitaine steers (average BW = 293.7 ± 38.88 kg) were grouped into 24 batches (10 steers/batch) and were randomly assigned to one of the three dietary treatments (eight batches per treatment), each supplemented with either 4% hydrogenated palm oil (PALM) or fatty acids (FAs) from olive oil (OLI) or soybean oil (SOY). No differences in growth performance or carcass quality were observed. For the meat quality analysis, a steer was randomly selected from each batch and the 6th rib on the left half of the carcass was dissected. PALM meat had the highest percentage of 16:0 ( P< 0.05) and the lowest n-6/n-3 polyunsaturated fatty acids (PUFA) ratio ( P< 0.05), OLI had the highest content of t 11-18:1 ( P< 0.01) and c 9,t 11-18:2 ( P< 0.05) and SOY showed the lowest value of monounsaturated fatty acids (MUFA) ( P< 0.001), the highest percentage of PUFA ( P< 0.01) and a lower index of atherogenicity ( P = 0.07) than PALM. No significant differences in the sensory characteristics of the meat were noted. However, the results of the principal component analysis of meat characteristics enabled meat from those steers that consumed fatty acids from olive oil to be differentiated from that of steers that consumed soybean oil.