Climate, grapes, and wine: structure and suitability in a variable and changing climate

The C-glycosidic ellagitannins constitute a subclass of hydrolyzable tannins of remarkable structural diversity. In this work we first achieved the hemisynthesis of flavano-ellagitannins, then we used them to develop a new efficient detection and quantification procedure for the C-glycosidic ellagitannins as well as flavano-ellagitannins.

Red wines felt as astringent and bitter generally show high content of tannins due to grape phenolic compounds’ extraction in the maceration process. Among different enological practices, mannoproteins have been shown to improve the mouthfeel of red wines (1) and the color (2,3). In this work, we evaluated the effect of mannoproteins on the mouthfeel profile of Sangiovese wines obtained by excessive tannin extraction.

With climate change, the occurrence of wildfires has increased in several viticultural regions of the world. Subsequently, smoke taint has become a major issue, threatening the sustainability of the wine industry.

A critical aspect of wine quality from a consumer perspective is the overall impression of wine flavour, which is formed by the interplay of volatile aroma compounds, their precursors, and taste and matrix components. Grapes contribute some potent aroma compounds, together with a large pool of non-volatile precursors (e.g. glycoconjugates and amino acid conjugates). Aroma precursors can break down through chemical hydrolysis reactions, or through the action of yeast or enzymes, significantly changing the aroma profile of a wine during winemaking and storage. In addition, glycoconjugates of monoterpenes, norisoprenoids and volatile phenols, together with sulfur-conjugates in wine, provide a reservoir of additional flavour through the in-mouth release of volatiles which may be perceived retro-nasally.

A pool of terpenoids possibly implicated in minty odours and in the appreciable refreshing sensation, has been identified in the ageing bouquet of red Bordeaux wines