New insights on thiol precursors catabolism by yeast during wine fermentation: identification of the N-Acetyl-L-Cysteine conjugate

Viticulture is exposed to a range of new stressors, that are challenging its sustainability and disrupting famous and well-established production regions. Steady increase of average temperature, recurring heat waves, altered rainfall seasonal distribution, drought spells, increased pathogens pressure, they all mix up with increased frequency, making every growing season a special challenge and calling for new approaches to cope with worrying scenarios.

Due to the central role of the ripening timing in the evaluation of the varietal response to the environmental resources, a method to manage maturation curves has been developed. The method produces an index of veraison precocity and overcomes several methodological problems, like the visual evaluation of the veraison point and the multi-annual and multi-varieties data processing. It is based on a statistical and mathematical processing of the sugar ripening curves.

The amino acids in grape juice are an important nitrogen source for yeast during alcoholic fermentation. Additionally, certain AAs are precursors to some of the volatile compounds found in wine and overall

Teran is an important native variety grown in Istria known for its high level of polyphenols and intensive fruity character of wines. Teran’s yield and wine typicity have recently decreased due to climate changes (increased temperature and severe drought). Four drip irrigation treatments (25%, 50%, 75%, 100% of total evapotranspiration) and control were investigated for the influence on Teran yield and quality, where focus was given to the content and composition of main polyphenolic and volatile compounds in grapes. Irrigation positively influenced yield since the berry weight also increased with increased irrigation. This resulted in the highest yield for 100% ETc. The highest concentration of polyphenols had control, while the irrigation treatments did not differ significantly. However, there was a tendency to decrease concentration with increased irrigation probably due to the increased berry size, which led to a dilution effect. Regarding the volatile compounds, the most abundant group was alcohols, followed by acids.

similar to other agricultural producers, grape growers face increasing pressure to improve productivity and production efficiency while reducing their environmental impact. Threats due to extreme climate events, as well as the uncertainty of available water and labor, provide significant challenges to the future of grape production. This presentation will provide an integrated overview of the tools and technologies being developed to address these issues and to help growers manage vineyards in the future, including vineyard design, remote and proximal sensing, automation, data management and decision support systems, and germplsm improvement. The potential impact of these advancements on vineyard productivity, fruit quality, and sustainability will be discussed.