Volatile composition of wines from cvs. Blanco lexítimo, Agudelo and Serradelo (Vitis vinifera) grown in Betanzos (NW Spain)

Wine aroma is formed by volatile compounds of different chemical natures and origins. Betanzos is the most northern viticole geographic area from Galicia (NW Spain). The aromatic profiles of wines produced from two white varieties (Blanco lexítimo and Agudelo) and one red variety (Serradelo) from Betanzos, harvested in 2006 and 2007, have been established by gas chromatography (GC/FID). A total of 35 varietal and fermentative aroma compounds were identified and quantified in free volatile form, which include terpenols, C13-norisoprenoids, alcohols, esters, volatile fatty acids and volatile phenols. To ascertain the compounds with major impact odours, the Odour Activity Value (OAV) was calculated. Twelve compounds showed concentrations above their perception threshold (OAV>1). The results obtained suggest that ethyl octanoate (apple), isoamyl acetate (banana), ethyl hexanoate (fruity) and β-damascenone (floral) were the most powerful odorants for the white wines Blanco lexítimo and Agudelo from Betanzos. Ethyl octanoate and β-damascenone (fruity and floral aroma respectively) were the most odorant for the red wine Serradelo.Xunta de Galicia (Spain)Adega Lorenzo Bescansa S.U.L

Acidification and pH Control in Red Wines

This chapter focuses on the management of acidic fraction and pH control in red wines. The main traditional strategies for chemical acidification and deacidification are discussed, including the use of acidic musts from low maturity grapes, as well as the addition of tartaric acid, malic, lactic, and citric acid, potassium bicarbonate, and calcium carbonate. Less common practices, such as deacidification by the addition of other salts, are also examined, together with new technologies, such as electrodialysis and the use of ion exchange resins. The effects of these techniques on wine pH as well as their impact on wine composition, stability, and sensory characteristics are considered, focusing on the problems of red wine processing. Finally, the main laboratory techniques for pH and acidity measurements are overviewed

Effect of a cold-active pectinolytic system on colour development of Malbec red wines elaborated at low temperature

The effect of a new cold-active pectinolytic system on colour of Malbec wines was studied under the following winemaking conditions: (i) fermentation at low temperature (20 °C) and (ii) prefermentative cold maceration (PCM) (5 °C–7 days) followed by traditional fermentation (28 °C). The pectinolytic system was mainly composed of polymethylgalacturonase and pectin lyase activities, detected under similar conditions to those in winemaking (pH 3.6–20 °C). The results show that the enzyme system significantly accelerated colour extraction by reducing the maceration time necessary for vinification at low temperature and shortening the PCM stage. Enzyme-treated wines exhibited better chromatic parameters than their controls at devatting and after 6 months of storage. The cold-active enzyme compensated the decrease in colour extraction due to the low maceration temperature, achieving high-quality wines with chromatic characteristics similar to those of traditional wines.Fil: Martín, María Carolina. Universidad Nacional de Cuyo. Facultad de Ciencias Aplicadas a la Industria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Morata, Vilma Ines. Universidad Nacional de Cuyo. Facultad de Ciencias Aplicadas a la Industria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentin

Determination of relationships among autochthonous grapevine varieties (Vitis vinifera L.) in the Northwest of the Iberian Peninsula by using microsatellite markers

Fifty six grapevine varieties traditionally grown in the Northwest region of the Iberian Peninsula were analysed for six microsatellite loci, in order to determine the relationships among them as well as the plant material that should be collected and preserved in germplasm banks. Previous morphological and molecular results were taken into account for assessment of the existing synonymies among accessions from different European countries. Percent distribution of the main alleles was calculated. Multivariate analysis was carried out and similarities among the studied material were described and commented.This work has been partially supported by the INIA (Spain) RF02-004-C5-1 project.Peer reviewe