All acids are equal, but some acids are more equal than others: (bio)acidification of wines

The contemporary wine sector confronts a formidable array of challenges, including burgeoning production costs and the constricted availability of natural resources. Heightened consumer awareness regarding sustainability issues further compounds these pressures, compelling companies to adopt more judicious resource utilization strategies. In response to these imperatives, there is a growing recognition of the need to overhaul production methodologies within the wine industry with a view to minimizing inputs and eliminating waste.

Historical phenology records have indicated that advances in key developmental stages such as budburst, flowering and veraison are linked to increasing temperature caused by climate change. Using phenological models the timing of grapevine development in response to temperature can be characterized and projected in response to future climate scenarios.
We explore the development and use of grapevine phenological models and highlight several applications of models to characterize the timing of key stages of development of varieties, within and between regions, and the result of projections under different climate change scenarios.

The quantity and distribution of polyphenols in musts play a fundamental role in the white winemaking. This is because these substances are exposed to oxidation reactions, which are catalysed by the polyphenol oxidase (PPO), leading to a decrease in the quality of the wines produced. PPO is inactivated by SO2, but currently, due to the restrictions of the legislation, other methodologies are being investigated. Ultra-High Pressure Homogenization (UHPH) is a non-thermal physic technology that exerts an ultrahigh pressure pumping (>200 MPa) of a fluid through a valve in a continuous system.

Cabernet Sauvignon is one of the most important winegrape varieties in Chile. However, temperature raise and decreased rainfall due to climate change can lead to grape quality decrease in certain areas. Amino acids are essential as nitrogen source for yeast but also directly affect grape quality serving as precursors of certain volatile compounds that enhance the wine bouquet. Besides, glutathione is an important tripeptide acting as antioxidant, preventing the appearance of browning pigments in must and exerts a protective effect in volatile compounds.

The quality of any alcoholic beverage depends on many parameters, such as cultivars, harvesting time, fermentation, distillation technology used, quality and type of wooden barrels (in case of matured drinks), etc.; however, the most important factor in their classification is content of volatile compounds.