Nucleophilic fraction to estimate the antioxidant activity of inactivated yeast derivates

The parameters that determine the grape quality, and therefore the optimal harvest time, suffer variations during berry ripening, related to climate change, with the widely known problem of the gap between technological and phenolic maturities. However, there are few studies about its incidence on grape nitrogen composition. For this reason, the use of an elicitor, methyl jasmonate (MeJ), alone or with urea, is proposed as a tool to reduce climatic decoupling, allowing to establish the harvest time in order to achieve the optimum grape quality. The aim was to study the effect of MeJ and MeJ+Urea foliar applications on the evolution of Tempranillo amino acids content throughout the grape maturation. Three treatments were foliarly applied, at veraison and 7 days later: control (water), MeJ (10 mM) and MeJ+Urea (10 mM+6 kg N/ha). Grape samples were taken at five stages of maturation: day before the first and second applications, 15 days after the second application (pre-harvest), harvest day, and 15 days after harvest (post-harvest). The amino acids analysis of the samples was carried out by HPLC. Results showed that the evolution of amino acids was similar regardless of the treatment; however, foliar applications influenced the nitrogen compounds content, i.e., there was no qualitative effect but quantitative one. Most of the amino acids reached their maximum concentration in pre-harvest, being higher in grapes from the treatments than in the control. In general, no differences in grape amino acids content were observed between MeJ and MeJ+Urea treatments. Foliar applications with MeJ and MeJ+Urea enhanced the grape amino acids content, without affecting their profile, helping to optimize their quality and allowing to establish a more complete grape ripening standard. Therefore, MeJ and MeJ+Urea foliar applications can be a simple agronomic practice, which has shown promising results in order to enhance the grape quality.

Global warming is accelerating the technological ripening of the grape, with a loss of acidity, which requires that vineyard management can delay ripening to avoid it. The source-sink relation is essential for grape ripening, since it affects the distribution of photosynthates and substances derived from plant metabolism. A work is proposed to know the response of the vineyard to the drastic reduction of the foliar surface by trim down the shoots in cv.

La salubrité du milieu et des aliments intervient de plus en plus lourdement, et souvent négativement, sur la santé de l’homme, aussi bien sur l’individu que sur la société tout entière.

The growing region of Barolo DOCG certified wines is topographically complex. The region is famous for this complexity and for the associated terroir driven Nebbiolo grapes and wines derived distinctly from this varietal. Although it is recognized that the Barolo area is unusual topographically and it is assumed that this unusual topography lends to the inherit terroir, the specifics of this relationship are less well defined.

Depuis le début des années 90, les vignerons des Caves Coopératives de l’Appellation “Côtes du Rhône” se sont penchés, au sein des structures de réflexion du Syndicat Général, sur deux axes de réflexion:
– Détermination des critères de sélection et de rémunération différenciée des apports de vendange;
– Organisation des sélections de vendanges sur la base des terroirs afin d’augmenter quantitativement le potentiel de sélection au sein de l’unité de production.