Chemical and sensory influences of the UV-C light of 254 nm in combination with the antioxidant substances in wine

Climate change constitutes an enormous challenge for humankind and for all human activities, viticulture not being an exception. Long-term strategic changes are probably needed the most, but growers also need to deal with short-term changes: summers that are getting progressively warmer, earlier harvest dates and higher pH in musts and wines. In the last 10-15 years, a relevant corpus of research is being developed worldwide in order to evaluate to which extent extreme canopy management operations, aimed at reducing leaf area and, thus, limiting the source to sink ratio, could be useful to delay ripening. Although extreme canopy management can result in relevant delays in harvest dates, longer term studies, as well as detailed analysis of their implications on carbohydrate reserves, bud fertility and future yield are desirable before these practices can be recommended.

Context and purpose of the study. The concept of terroir encompasses the investigation of the physical environment’s influence on grapevine physiology, grape composition, and wine quality, with an emphasis on employing viticultural zoning techniques to systematically characterize and analyze terroirs.

The chemical composition of grape berries at harvest is one of the key aspects influencing wine quality and depends mainly on the ripeness level of grapes. Climate change affects this trait, unbalancing technological and phenolic ripeness, and this further raises the need for a fast determination of the grape maturity in order to quickly and efficiently determine the optimal time for harvesting. To this end, the characterization of variety-specific ripening curves and the development of new and rapid methods for determining grape ripeness are of key importance.

Schiava cv. (germ. Vernatsch) is a group of grape varieties used for winemaking (e.g. Kleinvernatsch-Schiava gentile, Grauvernatsch-Schiava grigia, Edelvernatsch-Schiava grossa) historically reported in Northern Italy, Austria, Germany and Croatia. Beside common phenotypic traits, these varieties have been also hypothesized to share a common geographical origin in Slavonia (Eastern Croatia). Nowadays, Schiava cv. are considered historical grape varieties of northern regions of Italy such as Lombardy, Trentino and South Tyrol. Traditionally widely consumed locally and also exported, over the past decades there has been a steady drop in production of these grapes, although with a parallel increase in wine quality. In this report, the effects of three main enological variables on the chemical components of Schiava produced in South Tyrol (var. Schiava grossa) are investigated from grape to bottle.

Proseccco is a famous italian Protected Designation of Origin (PDO) produced in two regions: Veneto e Friuli Venezia Giulia, however, the production is mainly concentrated in the province of Treviso. These territories are characterized by plains with some hilly areas and temperate climate. Its Production regulation provides a minimum utilization of 85% of Glera grapes, a local white grape variety, and up to a maximum of 15% of other local and international varieties. Prosecco second fermentation takes place, according to the Charmat method, in autoclaves.