Les sols du cru de Bonnezeaux, Thouarcé, Anjou, France

Lugana Protected Designation of Origin (PDO) wines are made from Turbiana grapes. The aroma of Lugana wines results from the combined contribution of esters, terpenes, norisprenoids, sulfur compounds and the benzenoid methyl salicylate. This study aims to investigate how volatile aroma compounds are affected by different nitrogen supplies and yeast strains. Wines were produced with a standard protocol with 2021 Turbiana grapes with two different yeasts Zymaflore Delta e Zymaflore X5 (Laffort, France).During the alcoholic fermentation of the must, when H2S appeared, additions of various nitrogen supply were made: inorganic nitrogen, organic nitrogen, a mix of inorganic and organic nitrogen and organic nitrogen with an addition of pure methionine. During wine fermentation, a daily measurement of hydrogen sulfide was carried out.

Mannoproteins are macromolecules found on the surface of yeast cells, composed of hyperbranched polysaccharide negatively charged chains by mannosyl-phosphate groups, fixed to a protein core. during the alcoholic fermentation and aging on lees, these mannoproteins are released from the yeast cell wall and become the main yeast-sourced polysaccharide in wine. due to their techno-functional properties, commercial preparations of mannoproteins can be used as additives to better assure tartaric and protein stability.

Hydrogels are soil-conditioning materials capable of absorbing substantial amounts of water relative to their weight.

Viticulture is a major contributor to the antagonism of positive reputation and negative environmental impacts of agriculture. Vine contributes to structure landscape in the world, resulting, for example, in the delimitation of protected designations of origin (PDO). PDO vine is currently subject to the double challenge of sustainability and climate change adaptation. As vine is very sensitive to diseases and pests, vine requires a high use of pesticides to achieve its quality and yield goals. This high need for pesticides is the most important negative impact of environmental components.

In Enology the conventional processes of filtration for clarification and stabilization are giving place to alternative membrane processes, including nanofiltration (NF). Furthermore, the increased alcohol content in wines recorded in recent years became an important issue for all the main wine producing countries. Among techniques available to the wine industry to reduce the ethanol content, NF is certainly one of the newest. This study is focused on the evaluation of NF influence on wine physical-chemical composition, including mineral content, which in accordance to our best knowledge is a novelty.