Hanseniaspora in wine-making: their genetic modification and potential role in acid modulation

The use of toasted vine-shoots (SEGs) as an enological tool is a new practice that seeks to improve wines, differentiating them and encouraging sustainable wine production. The micro-oxygenation (MOX) technique is normally combined with alternative oak products with the aim to simulate the oxygen transmission rate that takes place during the traditional barrel aging. Such new use for SEGs implies a reduction in color due to the absorption by the wood of the responsible compounds, therefore, given the known effect that MOX has shown to have on the modification of wine color, its use together with the SEGs could result in an interesting implementation with the aim to obtain final wines with more stable color over time.

Carbonic Maceration (CM) winemaking is typically used in different European regions. But It is paradoxical that being a traditional processing system and widely used in many wineries, some of the phenomena that take place and the parameters that characterize them are barely known. In this vinification system the intact grape clusters are placed in a carbon dioxide (CO2) enriched medium, and they immediately change from a respiratory metabolism to an anaerobic fermentative metabolism called intracellular fermentation, which is carried out by grape enzymes. But some grapes located in the lower zone of the tank are crushed by the weight of the ones above and release must, which is fermented by yeasts.

The construction of vineyard landscapes along the Burgundy Côte is the result of geological processes and of human labour. Substratum diversity in this vineyard is the result of a very long history explained by the diversity of Jurassic sedimentary facies and Tertiary tectonic activity. The nature and thickness of Quaternary deposits (Weichselian scree debris and alluvial fans) reflect sediment dynamics concurrent with the last glaciation.

Grapevine (Vitis vinifera L.) is a challenging plant species to transform and regenerate due to its complex genome and biological characteristics. This limits the development of cisgenic and gene-edited varieties. One hurdle is selecting the best starting tissue for the transformation process, much like isolating suitable tissue for protoplasts. One promising method involves delivering crispr/cas components to protoplasts isolated from embryogenic calli, which are then induced to regenerate.

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.