Influence of some oenological practices on the aromatic and sensorial characteristics of white Verdejo wines

Changes in the aromatic composition as well as sensory characteristics in Verdejo white wines were analysed based on two factors: the winemaking methodology and the storing time of wine in bottles. The volatile components were determined by GLC-MS, and the sensory profile was designed and assessed according to the ISO 11035 standard. The results showed that when wines were made in oak barrels, either completely or partially, which means the wines were in contact with the lees, the levels of 1-octanol, ethyl heptanoate and ethyl decanoate were significantly affected (P menor que 0.05); the softness sensation was also influenced (P menor que 0.05). However, the amount of time the wines were stored in bottles significantly affected (P menor que 0.05) the levels of 1-hexanol, ethyl heptanoate, ethyl octanoate, ethyl decanoate, hexyl acetate, isoamyl acetate and isoamyl lactate and also an odour note (tropical fruit). The compounds with higher OAV values belong to the groups of esters and fatty acids. For these reasons, the composition and the quality of the aroma of Verdejo white wines appear to be significantly affected both by use of oak barrels in winemaking and the time the wines are stored in bottles.

Improvement of compatibility and stability on polyethylene-modified bitumen by use of an aromatic extra as compatibilizer.

Bitumen modification by polyethylene addition usually improves the mechanical properties of the binder and, therefore, the behavior in service of the bituminous mix: thermal susceptibility and rutting can be diminished, whilst the resistance to low temperature cracking may increase. To achieve this improvement it is necessary a good compatibility between the base bitumen and the polyethylene. Low compatibility between bitumen and polyethylene can lead to phase separation: the polymer- asphalt incompatibility translates into a deterioration of ultimate properties. The object of this research project was to determine if these problems can be diminished by using certain compatibilizer agents, e.g. an aromatic extract from the oil refinery. Compatibility and stability of the polyethylene modified bitumen were studied using conventional test methods and dynamic shear reometer (DSR). Blends of bitumen and polyethylene were prepared with neat bitumen (PMB) or bitumen with compatibilizer as component of the binder (PMBC) and then compared. The experimental results show that “colloid instability index”(IC) is a parameter that can be used to control the compatibility between bitumen and polyethylene. From polyethylene point of view, one of the parameters that govern is the “melt flow index” (MFI). Experimental results show that PMBC formulated with low IC bitumen and hi gh MFI lineal polyethylene can be considered as stable binder.

Summer rainfall variability in European Mediterranean mountains from the sixteenth to the twentieth century reconstructed from tree rings.

En este trabajo se utilizan dendrocronologías para reconstruir la precipitación estival.

Summer rainfall variability in European Mediterranean mountains from the sixteenth to the twentieth century reconstructed from tree rings.

Estudio dendrocronológico de estructuras arbóreas en alta montaña mediterránea.

Origen y distribución de los hidrocarburos policíclicos aromáticos en sedimentos actuales de la Laguna de El Hito (España central)

Se llevó a cabo la evaluación ambiental y el estudio del estado actual de la cuenca de la Laguna de El Hito referido a 18 hidrocarburos policíclicos aromáticos (PAHs) de 2 a 6 anillos bencénicos. Se determinó su origen a partir de diversos índices (%naftaleno, Fen/Ant y Flu/Pir), interpretándose tanto fuentes no antropogénicas (petrogénica) como antropogénicas (pirogénica). Se obtuvieron los mapas de distribución de las concentraciones de PAHs y de sus índices para localizar los puntos de concentraciones más elevadas. Ningún PAH superó las concentraciones marcadas por los Niveles Genéricos de Referencia (NGR) para la salud humana en los distintos usos del suelo del R.D.09/2005. Los PAHs con las mayores concentraciones fueron el naftaleno y el fenantreno.Environmental evaluation and analysis of the current state of El Hito Lake Basin referred to 18 polycyclic aromatic hydrocarbons (PAHs) with 2 to 6 benzene rings was carried out. Different indexes were used to determine the source of PAHs (% naftalene, Phe/Ant and Flu/Pyr). Both non anthropogenic (petrogenic) and anthropogenic (pyrogenic) sources were interpreted. Distribution maps for PAHs and indexes were plotted to locate the position of the higher concentrations and, therefore, their possible sources. None of these compounds showed concentrations above the Soil Screening Levels (SSL) for human health in the different uses of soil as is established in R.D.09/2005. The ones that reached the highest concentrations were naphthalene and phenanthrene.