Comparative studies on the dynamics of fermentation of selected wine yeasts

In modern viticulture, sustainability must be considered not only into the winery, but in the vineyard as well, being that with the most attentive interventions in order to protect the environment. In this context, the new “fungi resistant” varieties represent a valid option for reducing the negative environmental impact of agrochemicals used in viticulture, including those ones used in organic farming (given the copper accumulation into soils). Several application studies have demonstrated the enological validity of many resistant varieties, both in price and as a blend. Also, under the production point of view, the feasibility and economical sustainability of the new resistant varieties was verified. The aim of this work was to deepen the knowledge on the organoleptic characteristics of wines obtained from the Fleurtai and Soreli varieties and to compare them with the wine obtained from Tocai Friulano, the mother variety in the area destined for the production of the Lison Classico DOCG appellation. The purpose of the work is then to verify the possibility of introducing resistant varieties into the DOCG while maintaining the wine name of the appellation linked to the territory.

Dans la region Nord-Est du Brésil, située à la Vallée du São Francisco, localiséee entre les paralleles 8-9º HS, la production de vins tropicaux a commencé il y a une vigntaine d’années. Dans cette région, il est possible d’avoir au minimum deux récoltes par an, car la moyenne de température est de 26 ºC, avec une pluviosité moyenne de 550 mm entre les mois de janvier-avril.

Trends already extended for more than 12 years show a decline in both consumption and international trade, particularly in volume. However, there are also positive signs in several categories of wine, segments and markets, as well as a better trend in terms of value. How are these trends affecting wine producers and distributors? Are they short or long term? do they mean radical and permanent changes to which a way of adaptation has to be found or are they just temporary changes that may only require some calm? How are companies adapting to these new trends? Which are their effects on wine regions?

Laboratório de Análisis del Aroma y Enologia (LAAE). Department of Analytical Chemistry, Faculty of Sciences, Universidad de Zaragoza, 50009, Zaragoza, Spain, During alcoholic fermentation, fusel (or Strecker) aldehydes are intermediates in the amino acid catabolism to form fusel alcohols following the Ehrlich Pathway (1). One of the main enzymes involved in this pathway is Alcohol Dehydrogenase (ADH), whose activity is highly strain dependent and determines the rate of conversion of aldehydes into fusel alcohols (2). This enzyme has a Zn2+ catalytic binding site, which suggests that the must Zn2+ levels will most likely influence the rate of reduction of aldehydes into alcohols. On the other hand, SO2 is commonly used in winemaking for its antiseptic and antioxidant properties.

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.