Influence of Partial Rootzone Drying on grape and wine anthocyanin composition

In red wine production, phenolic maturity is becoming increasingly important. Anthocyanins, flavonoids and total polyphenols content and availability significantly influence the harvest time of wine grapes while, during vinification process, their extraction strongly affects wine body, color and texture

Chemical studies aiming at assessing how a wine reacts towards oxidation usually focus on the characterization of wine constituents, such as polyphenols, or oxidation products. As an alternative, the key oxidation intermediate hydrogen peroxide H2O2 has never been quantified, although it plays a pivotal role in wine oxidation. H2O2 is obtained from molecular oxygen as the result of a first cascade of oxidation reactions involving metal ions and polyphenols. The produced H2O2 then reacts in a second cascade of oxidation to produce reactive hydroxyl radicals that can attack almost any chemical substrate in wine.

Estudio comparativo del comportamiento de ocho variedades de viníferas blancas en el Penedés, injertadas sobre los portainjertos 41-B y 110-R.
Se describen los comportamientos

Under the pressure of global warming, several wine grape growing regions around the world are increasingly suffering from advanced and compressed phenology; endangering wine character while also creating serious logistic problems. From a physiological standpoint, the issue of delaying ripening is not simple as, in several instances, only a few processes must be delayed (i.e. sugar accumulation into the berries) while other events such as pigmentation and accumulation of other important phenolic compounds should proceed at a normal rate. Thus, the issue of decoupling technological maturity from phenolic maturity is another important consideration. Over the last decades, several research groups have endeavored to establish alternate cultural practices aimed at addressing this decoupling. In some cases, special applications of quite robust and well known practices regarding physiological principles have been utilized, however some completely new techniques are also being studied. In figure 1 of the review, we offer a panorama of the available tools and in the text we elaborate on those having provided most reliable and consistent results under an array of genotypes and environmental conditions. Among these, primary focus is given to post‐veraison—apical to the cluster—leaf removal (that can also be suitably replaced by applications of anti‐transpirants); the use of kaolin against multiple summers’ stresses; and a drastic version of late winter pruning having the potential to postpone ripening into a cooler period with improved grape composition and a limited negative impact on yield and storage reserves replenishment. 

The persistence of effervescence and foam collar during a Champagne or sparkling wine tasting constitute one, among others, specific consumer preference for these products. Many different factors related to the product or to the tasting conditions might influence their behavior in the glass