Soil management with respect to nitrogen mobilization and nutrient supply of grapevines on loess soil

The quality of grapevines measured by yield and must density in the northern part of Europe conditons can be characterized as a type of “cool climate” – vary strongly from year to year and from one production site to another. One hundred year observations in Johannisberg from 1890 to 1991 demonstrate for the yield formation a clear dependancy from the year combined with a steady increase in productivity; latter a proof of positive clonal selection efforts.

AIM: Stalks are empirically known to bring many benefits to the wine such as alcoholic reduction, color protection or improvement of the tannic intensity. Not much used on Swiss grape varieties, the aim of this study was to identify the relevance of using this type of winemaking in the case of Gamay and Gamaret red grape varieties.

Melatonin is a bioactive compound with antioxidant properties, that has been found in many fermented beverages, such as beer and wine [1]. Indeed, it has been shown that yeast can synthesize melatonin during alcoholic fermentation, although its role inside the cell, as well as the metabolic pathway involved in its synthesis, is still unclear [1]. Recent studies showed that during fermentation, melatonin interacts with different proteins of the glycolytic pathway in both Saccharomyces and non-Saccharomyces yeast, for instance glyceraldehyde 3-phosphate dehydrogenase, pyruvate kinase or enolase [2].

A pool of terpenoids possibly implicated in minty odours and in the appreciable refreshing sensation, has been identified in the ageing bouquet of red Bordeaux wines

The management of oxygen during winemaking and aging is a big issue in order to achieve high quality wines. The correct amount of O2 improves aroma, astringency, bitterness and color, however an excess of oxygen promotes the appearance of yellow