Influence of Yeast Strain, Bentonite Addition, and Aging Time on Volatile Compounds of Sparkling Wines

Abstract

The composition of the volatile fraction of sparkling wines prepared according to the traditional, or champenoise, method can be influenced by different variables. This study examined the influence of the yeast strain used in the second fermentation, the addition of sodium bentonite to the tirage solution, and the aging time with yeast on the volatile compounds of sparkling wines. From a single base wine, five batches of sparkling wines were obtained industrially in duplicate using five different yeast strains. One duplicate of each strain was prepared with the addition of sodium bentonite to the tirage solution. Samples were taken after 20, 40, 90, 180, 270, and 365 days. Major volatile compounds were determined by direct injection in a gas chromatograph while several minor volatile compounds were determined by injection of the extract obtained by headspace solid-phase microextraction on a poly(dimethylsiloxane) fiber. Analysis of variance and two multivariate statistical techniques (cluster and stepwise discriminant analysis) were applied to the data. It was verified that neither yeast strain nor addition of bentonite to the tirage solution greatly influenced the volatile composition of the wines, while aging time did have a great influence. In the course of aging of wine with yeast, simultaneous degradation and synthesis of volatile compounds occurs and at any given time either of these processes can predominate, explaining the disparity of the results of different authors in the literature.