Effect of Yeast Derivatives and β-Glucanases on Ageing over Lees Process of Tempranillo Red Sparkling Wine.

This study focuses on improving the second fermentation and the in-bottle ageing over lees process for 9 and 21 months of a red sparkling wine. The aim of the study was to enhance wine quality and try to make it more pleasant for consumers. For this purpose, four different yeast derivatives (yeast walls, yeast walls with tannins, inactivated yeasts and mannoproteins) and β-glucanases were added to a red base sparkling wine and were aged over lees during two different periods: 9 and 21 months. Oenological parameters, total polysaccharides, total proteins, free amino nitrogen, phenolic composition, foaming properties, and volatile compounds were analysed in conjunction with a sensory evaluation. Results show the different incidences of the studied adjuvants on the final parameters, highlighting the importance of the interactions of the studied adjuvants over time. In fact, time itself turned out to be one of the main factors affecting the final characteristics of the wine, so influencing consumers' opinions and modifying the wine's acceptability and quality. [ABSTRACT FROM AUTHOR]