The effect of soil and climate on the character of Sauvignon blanc wine

Irrigation is an important practice to influence vine quality, especially in Mediterranean regions, characterized by hot summers and severe droughts during the growing season. This study focused on deficit irrigation regime influence on amino acids composition of Monastrell grapevines under semiarid conditions (Albacete, Southeastern of Spain). In 2019, two treatments were applied: non-irrigation (NI) and regulated deficit irrigation (RDI), watered at 30% of the estimated crop evapotranspiration from fruit set to onset of veraison. Grape amino acids content was analyzed by HPLC. Berries from non-irrigated vines showed higher concentration of several amino acids, such as tryptophan (73%), arginine (70%), lysine (36%), isoleucine (27%), and leucine (21%), compared to RDI grapes. Arginine is, together with ammonium ion, the principal nitrogen source for yeasts during the alcoholic fermentation; while isoleucine, tryptophan, and leucine are precursors of fermentative volatile compounds, key compounds for wine quality. Moreover, NI treatment increased in a 14% the total amino acids content in grapes compared to RDI treatment. The reported effects might be because yield was 70% higher in RDI vines than in the NI ones and, therefore, the sink demand was increased in the irrigated vines. In addition, NI vines suffered more severe water stress and it is known that the amino acids synthesis and accumulation can be influenced by the plant response to stress. According to the results, the irrigation regime showed effect on amino acids concentration in Monastrell grapes under semiarid conditions. Grapes from non-irrigated vines showed a higher content of several amino acids relevant to the fermentative process and to the wine aroma compounds formation. It is demonstrated that the final content of nitrogen-related components in grapes is influenced by the irrigation regime. The convenience of the irrigation strategy to suggest will depend on the desired wine style and the target yield levels.

The C-glycosidic ellagitannins constitute a subclass of hydrolyzable tannins of remarkable structural diversity. In this work we first achieved the hemisynthesis of flavano-ellagitannins, then we used them to develop a new efficient detection and quantification procedure for the C-glycosidic ellagitannins as well as flavano-ellagitannins.

The ability of grapevine cultivars and rootstocks to cope with and adapt to recurring water constraints is the focus of this study. The contribution of intrinsic (epigenetic) and extrinsic (rootzone microbial community) factors to water stress resilience will be discussed. The study was conducted in a validated model vineyard where three scion cultivars (Pinotage, Shiraz, and Cabernet Sauvignon) on two rootstocks (Richter 110 and USVIT8-7) grow under recurring seasonal water constraint (and control) scenarios since planting (in 2020). Comprehensive profiling of the site, soil, atmospheric conditions, plants, and their physiological responses provide contextual data for the analyses conducted.

Fining is a technique that is used to remove unwanted wine components that affect clarification, astringency, color, bitterness, and aroma. Fining involves the addition of adsorptive or reactive material in order to reduce or eliminate the presence of certain less desirable wine components and to ensure that a wine remains in a particular stable state for a given period of time Recently concerns have been raised about the addition of animal proteins, such as gelatin, to wine due to the disease known as bovine spongiform encephalopathy (Mad Cow disease). Although the origin of gelatins has been moved to porcine, winemakers are asking for substitute products with properties and application protocols similar to the traditional animal-derived ones, making the use of plant-derived proteins in fining a practically viable possibility. As a consequence, various fining agents derived from plants have been proposed, including proteins from cereals, legumes, and potato.

The research is part of the “Ecovinegoals” project, financed by Interreg Adrion funds. It aims to encourage the adoption and dissemination of agroecological practices in intensive wine-growing areas. The study focuses on cost analysis of the wine-growing landscape enhancement in an organic winery in order to provide a useful tool for winemakers to direct their investments in green infrastructures. One of the Italian pilot areas of the Ecovinegoals project is the Venezia Biodistrict, characterized by viticulture in a flat reclamation area of 105,800 hectares.