The interactions of wine polysaccharides with aroma compounds, tannins, and proteins, and their importance to winemaking

A current research interest of the wine industry is the improvement of wine quality by producing wines to meet the consumers’ demands and desires. However, this requires an understanding of the complex chemical matrix and the nature of interactions between molecular components of the wine. Wine polysaccharides are macromolecules whose presence and interactions with other wine components can lead to the modulation of technological and organoleptic wine quality attributes. Indeed, grape and yeast derived polysaccharides play a major role in modulating wine astringency through interactions with exogenous salivary protein-tannin complexes formed within the oral cavity. Polysaccharides participate in the formation of colloidal particles through their interactions with wine tannins and proteins, with crucial implications on the clarity and stability of finished wines. Additionally, polysaccharides modulate wine aroma volatility and foaming. The extent to which they influence these attributes is dependent on the concentration and physico-chemical properties of all the species involved in these interactions. Overall, the structure, size and type of the polysaccharides are key components governing the success and intensity of their interactions with other species. Therefore, to better understand the relevance of polysaccharides in wine, this review discusses the molecular interactions facilitated by these species and details their potential roles within the wine matrix.