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Red grape varieties are characterized by different phenolic contents (prominently tannins and anthocyanins) found in skins and seeds. The extractability of these compounds varies during maceration, as well as the mechanical properties of skins and seeds. Four main Italian red winegrape varieties were tested to understand these differences during a simulated maceration process.

Mercury is one of the hazardous contaminants that may be present in the environment. Moreover, its toxicological effects are strongly dependent on the chemical form of the element, being the organic species the most toxic. In spite of this, the determination of mercury compounds in environmental samples, such as water, soils, sediments and biological matrixes, is of great importance. This review examines the current state of the sample treatments that have been developed, during the last 18 years (1990-2007),previous to separation and detection of mercury compounds, namely acid lixiviation, distillation,alkaline digestion and supercritical fluid extraction, as well as of the chromatographic techniques (gas chromatography and high performance liquid chromatography) used in order to separate mercury compounds and detection techniques usually coupled with them. The detection limits and the linear range achieved coupling both separation techniques with different detectors are presented, as well as the advantages and disadvantages of each one. Finally, a brief discussion over the most used detection systems is also presented.

The fate and reactivity of anthropogenic mercury in aquatic environment is of major concern owing to its toxicity to most organisms and man. In Ria de Aveiro, a chloralkali plant has been discharging mercury during decades into one of the remotest branches. Most of the discharged mercury settles down in Largo do Laranjo, an inner bay of 1.5 km'. Since 80's, several works have identified high mercury concentrations in sediments, suspended particulate matter and water [I, 2, 3]. The highest concentrations of mercury (max. 35 Og g") were found in sediments at 40 cm depth, corresponding to the period of maximum industrial production [2]. However, there is an escape of particulate mercury when surface sediments are resuspended and transported by the tide to the rest of the lagoon [4].

Aroma is an identifying characteristic of wines and is of crucial importance for the consumer appreciation. Among all odour-active compounds, some key molecules appear only after ageing and give a strong contribution to both identity and added value of the wine bottle. Methyl salicylate (MeSA) is an odorant which usually appears after ageing and could provide an increase in fruity aromas and freshness. This odour-active ester can be found mainly bound to one or more carbohydrates, forming a glycoside. In wines, the hydrolysis of glycosides contributes to the aroma evolution of wine. In our previous works, MeSA was found in relevant content, both in bound and free form, in some genetically related Italian varieties such as Trebbiano di Lugana, Trebbiano di Soave (both employed in the production of Lugana wines), and Verdicchio. In this research, a straightforward filter-and-shot LC-MS/MS method was used for the determination of 7 different MeSA glycosides in 246 samples representative of 18 different monovarietal Italian white wines. MeSA glycosides were found in relevant concentrations in Verdicchio and Lugana wines, whereas they were determined for the first time in all others. Results were in accordance with the literature since Lugana and Verdicchio emerged for the total amount of glycosides, together with Erbaluce, whose richness was not known to date. This trend was observed for all analytes, with stronger intensity, especially in MeSA–glucoside, MeSA–gentiobioside and MeSA–violutoside. The triglycosylated form was not detected in any case. The same trend was also observed for the free form, whose value was not above the olfactory threshold for any sample. MeSA in all its forms also showed a qualitative trend, with MeSA - glucoside and MeSA–primeveroside emphasised in richer cultivars with also a characteristic pattern. The knowledge of the concentration of MeSA glycosides could be considered a potential predictor of the potential evolution of white wines towards balsamic like nuances

Grape-derived tannins are important constituents of red wine, contributing to its color, mouthfeel and aroma longevity. In particular, tannins are associated with the perception of astringency, namely the trigeminal sensation of friction perceived in the oral cavity, arising from precipitation of salivary proteins by wine tannins. The quantity of tannins present in a wine varies largely depending on grape variety and winemaking practices. However, in spite of tannin concentration, certain wines exhibit pleasant velvety astringency, while others provide less pleasant sensations of grainy, drying astringency. The chemical nature of these different astringent characteristics of wine is in large part unknown. With over three-hundred grape varieties, Italy owns one of the richest ampelographic heritages worldwide. Remarkably, a large number of these grapes form the basis of the different Italian wine appellations, so that such biodiversity stretches from the vineyard to the consumer. Italian wines represent therefore an ideal case to investigate the chemical and biochemical diversity of tannins and to understand the specific molecular patterns that differentiate Italian wines. This project, supported by Italian Ministry of Scientific Research within the PRIN scheme, will revolve on mono-varietal wines of ten of the major Italian grapes, produced in their respective areas of origin. Wines will be submitted to a comprehensive pool of analyses including quantification of tannins by precipitation methods, evaluation of their degree of polymerization and other compositional factors, untargeted LC-MS analysis, macromolecule composition, spectroscopic (UV-Vis and MIR) and electrochemical characterization, saliva precipitation index and sensory assessment. The results will allow to shed light on the chemical diversity existing among different wines with regard to their tannin composition, in an attempt to unravel the complex relationship existing between wine composition and perceived astringency. Preliminary data on the chemical composition of the wines under investigation will be presented.