The influence of different fertiliser applications and canopy management practices on the potassium content and pH of juice and wine of Vitis vinifera L. cvs. Cabernet-Sauvignon and Cabernet franc

The presence of grape-derived heat unstable proteins can lead to haze formation in white wines [1], an instability prevented by removing these proteins by adding bentonite, a hydrated aluminum silicate that interacts electrostatically with wine proteins leading to their flocculation. Despite effective, using bentonite has several drawbacks as the costs associated with its use, the potential negative effects on wine quality, and its environmental impact, so that alternative solutions are needed.

Aims: Most consumer research about terroir has focused on wine, particularly with French or other European wine drinkers, rather than those in the Anglo-Saxon world. In Europe, whilst there is no agreement amongst consumers as to what terroir actually is, there is a general recognition of the word and an acceptance that it represents something important

It is well known that free varietal thiols, in particular 3-mercaptohexanol (3MH) and 3-mercaptohexyl ace-tate (3MHA), are important constituents to the aroma of New Zealand Sauvignon blanc wines.

The application of different winemaking techniques helps to modify the basic parameters, phenolic profile, and aroma components influencing the final wine quality. In particular, pre-fermentative processes aim to increase the extraction and preservation of grape native compounds. Among them, cold liquid stabulation (macération sur bourbes) consists in maintaining the grape juice on its lees, in suspended condition at low temperature (0-8 °C) for a variable time (generally from 7 to 21 days). The aim of this work is to apply the cold liquid stabulation on two Italian white grape varieties, Arneis and Cortese, to evaluate the impact on basic parameters, color, polyphenolic compounds (TPI), antioxidant power (DPPH), total polysaccharides, and free and glycosylated volatile compounds (GC-MS analysis) during and after the process.

Fumaric acid has been approved by the OIV in 2021 for its application on wine to control the growth and activity of lactic acid bacteria. Fumaric acid is currently being evaluated by the OIV as an acidifier of must and wine. Investigations during the 2023 vintage provided further information on its use on must or during AF, thus completing information provided during the previous vintage.