Aplicación de la Calorimetria Diferencial de Barrido (CDB) en la caracterización del aceite de oliva virgen

Application of Differential Scanning Calorimetry (DSC) to Virgin Olive Oil has been evaluated. Thermal profile of olive oil from six cultivars were analysed by DSC. Crystallization and melting curves were obtained between -100ºC and 50ºC, at 5ºC/min, showing profiles differentiated according to each. Temperature peak (Pt) from exothermic and endothermic transitions show a good correlation with the triacylglycerol composition. Oxidation DSC curves were obtained between 50ºC to 300ºC, under air flow rate of 100 mL/min. The oxidation times (To) obtained from each oil show a high correlation, r>0.95, with the oxidative stability measured by Rancimat method.Se analiza la viabilidad de la calorimetría diferencial de barrido (CDB) en su aplicación a la caracterización del aceite de oliva virgen. Las curvas de cristalización y de fusión obtenidas, entre - 100ºC y 50ºC a una velocidad de 5ºC/min y a partir de seis variedades distintas de aceite de oliva, presentan perfiles diferenciados según la variedad a la que pertenece el aceite, mostrando picos de temperatura exotérmicos y endotérmicos cuyos valores mantienen una estrecha correlación con respecto a las diferentes composiciones triglicerídicas de las distintas variedades. Igualmente, las curvas de oxidación CDB, realizadas en atmósfera oxidante entre 50ºC y 300ºC y flujo de aire de 100 mL/min, proporcionan datos del tiempo de oxidación de estos aceites con una correlación de r>0.95 respecto de los datos de estabilidad proporcionados por el método Rancimat

Calorimetria diferencial de barrido. Influencia de la composición del aceite de oliva virgen en su perfil térmico

Samples of olive oil from the cultivars ‘Arbequina’ and ‘Picual’, with different contents in polyphenols, were analyzed by means of differential scanning calorimetry. Three speeds of cooling/heating (1, 5 and 10ºC/min) were analyzed with the differences between duplicates being lowest when the analysis was carried out at 5°C/min. An important varietal effect (pMuestras de aceite de las variedades ‘Arbequina’ y ‘Picual’, con diferentes contenidos en polifenoles, son analizadas mediante calorimetría diferencial de barrido a 1, 5 y 10 °C/min de velocidad de enfriamiento y de calentamiento, obteniéndose las diferencias entre duplicados más bajas cuando el análisis se efectúa a 5 ºC/min. Se observa un efecto varietal importante (

Virtualización del Título Propio en Olivicultura y Elaiotecnia. Elaboración de Materiales

Es conocido que España es primer país productor de aceite de oliva del mundo, con un 40 % de la producción mundial y el 50 % de la producción de la Unión Europea, siendo la provincia de Jaén, con el 38,4 % de la producción española, la mayor zona productora del mundo en aceite de oliva. Sin embargo, se trata de un sector en el que la escasa profesionalización es, tal vez, su mayor debilidad.La Universidad de Jaén, consciente del importante papel que ha de jugar como Institución dinamizadora del desarrollo de su entorno, en el que el sector del olivar y del aceite de oliva tiene una enorme importancia, considera que es urgente formar titulados universitarios de grado superior que posean conocimientos integrales y solventes en olivicultura y elaiotecnia de modo que incorporados a las empresas del sector del olivar y el aceite de oliva o creando las suyas propias, lo modernicen y desarrollen, contribuyendo a dotarlo de cultura empresarial y al desarrollo socioeconómico y, por ende, al bienestar de los ciudadanos de la provincia

Influence of fertigation in "Manzanilla de Sevilla" olive oil quality

6 pages, 1 figure, 5 tables, 48 references.We report the results of a study carried out in a ‘Manzanilla de Sevilla’ olive orchard near Seville, Spain, where the influence of different fertigation treatments on oil chemical composition was considered. Four treatments were established: control (no fertilizer) and T200, T400, and T600 in which each tree, respectively, received 200, 400, or 600 g N per irrigation season of a 4N–1P–3K complex fertilizer applied daily from 1999 to 2003. Results shown here correspond to the last 2 years of the experiment, 2002 and 2003. Fruits were sampled at the beginning of ripeness at the ‘‘green’’ stage. Fruit water content increased with the amount of fertilizer, probably because of the increase of potassium in the pulp. Oil content was unaffected by the treatments, but oil yield increased with the fertilizer dose in 2003 as a result of the number of fruits per tree. Polyphenol content, which is related to antioxidant oil capacity, K225 (bitterness), and oxidative stability were lower in the oils made from trees receiving greater fertilizer doses. The monounsaturated fatty acid content, in particular oleic acid, decreased with increasing amounts of applied fertilizers, whereas polyunsaturated fatty acids, in particular linoleic acid, increased with it.Peer reviewe

Sap flow as a tool to enhance fruit quality: The case of olive oil

8 páginas.- 3 figuras.- referencias.- Comunicación oral presentada en el XI International Workshop on Sap Flow 7-11 Oct. 2019 in Hyytiälä (Finland)Olive oil is considered as one of the healthiest oils for human consumption due to its high amount of monounsaturated fats and also to the content of antioxidants, polyphenols and triterpenes. Among these last compounds, the oleanolic acid and maslinic acid are of great interest because they are shown to have anti-tumoral and anti-cancer activity. Interestingly, water stress has been observed to enhance these compounds in olive oil. Thus, an irrigation tool based on tree physiology to manage the water stress level would be useful for improving health benefits of olive oil. The general objective of our work was to develop an irrigation approach, based on sap flow-related measurements, to evaluate and control the water stress of olive trees in order to increase the above-mentioned compounds in olive. To achieve this objective we conducted an experiment having four irrigation treatments, where we applied 100, 75, 50 and 25% of the irrigation needs. Sap flow gauges were installed in 16 olive trees, four replicates for each irrigation treatment, to estimate sap flux density by the compensation heat flux method. Sap flux density was used to estimate stomatal conductance in a continuous manner, using a method developed previously for olive. This simulated stomatal conductance was linked to a biochemical model of CO2 assimilation to estimate daily photosynthesis. Moreover, we determined the carbon isotope ratio (δC) in oil of the same monitored trees, as well as the oil compounds above-mentioned. Our results showed that those trees with a higher water supply had higher accumulated photosynthesis on a daily and seasonal basis. Oil δ13C showed the same trend, confirming the effect of stomatal closure on reduction of oil synthesis and the robustness of our methodological procedure to estimate gas exchange from sap flux density dynamics. Furthermore, the level of stomatal conductance achieved correlated inversely with the concentrations of oleanic acid and maslinic acid in the oil. Our results encourage the potential use of sap flow-related measurements to manage irrigation and control the desired level of water stress based on physiological criteria, which could be useful to improve the content of relevant compounds in olives.This work was funded by the Centro para el Desarrollo Tecnológico Industrial and the research project AGL2015-71585-R (Spanish Ministry of Science and Innovation), the European project ERA-NET JPI-Waterworks (PCIN-2017-002, UE) and Grupo Castillo de Canena. A. Pérez-Martı́n and R. Romero helped us with the field measurements

Influence of Fertigation in ‘Manzanilla de Sevilla’ Olive Oil Quality

We report the results of a study carried out in a ‘Manzanilla de Sevilla’ olive orchard near Seville, Spain, where the influence of different fertigation treatments on oil chemical composition was considered. Four treatments were established: control (no fertilizer) and T200, T400, and T600 in which each tree, respectively, received 200, 400, or 600 g N per irrigation season of a 4N–1P–3K complex fertilizer applied daily from 1999 to 2003. Results shown here correspond to the last 2 years of the experiment, 2002 and 2003. Fruits were sampled at the beginning of ripeness at the ‘‘green’’ stage. Fruit water content increased with the amount of fertilizer, probably because of the increase of potassium in the pulp. Oil content was unaffected by the treatments, but oil yield increased with the fertilizer dose in 2003 as a result of the number of fruits per tree. Polyphenol content, which is related to antioxidant oil capacity, K225 (bitterness), and oxidative stability were lower in the oils made from trees receiving greater fertilizer doses. The monounsaturated fatty acid content, in particular oleic acid, decreased with increasing amounts of applied fertilizers, whereas polyunsaturated fatty acids, in particular linoleic acid, increased with it

Improving flood resilience through governance strategies: Gauging the state of the art

There has been an upsurge in studies of flood risk governance (FRG): steering and decision-making by public and private actors as a complement to risk assessments and technical management options. The scholarly debate is, however, highly fragmented, complicating the production of cumulative insights. To address this knowledge gap, we used six governance strategies for achieving flood resilience that previously have been put forward as a conceptual framework to review 121 articles published between 2016 and 2019, complemented with insights contained in recent overview articles, to gauge the state-of-the-art in FRG literature: to (a) diversify flood risk management strategies; (b) align the strategies; (c) adequately involve private actors, including citizens; (d) put an adequate rule system in place; (e) cater for sufficient monetary and non-monetary resources; (f) inspire an open and inclusive normative debate. We found, first, that literature is producing insights on increasingly technically advanced risk assessments and agent-based models but societal debate on justice in flood risk governance is getting attention. A clearly emerging topic is that of citizen engagement in flood risk governance. Second, the geographical focus of the studies is still skewed toward the Global North. To make progress in understanding flood risk governance for better resilience more systematic and comparative empirical assessments of flood risk governance in order to derive generalizable lessons while better taking into account the context-specificity of FRG. Testing flood risk governance solutions against comparative cases, by balancing the geographical scope of research efforts, and enhancing interdisciplinary and transdisciplinary working is a way to deliver knowledge for more resilience. This article is categorized under: Human Water > Water Governance Engineering Water > Planning Water