Effect of the addition of bentonite to the tirage solution on the nitrogen composition and sensory quality of sparkling wines.

When producing sparkling wines by the traditional method, a small amount of bentonite is added to the tirage solution to help with the flocculation of the yeast. This work studies the effect of this addition on the nitrogen composition and sensory quality of the sparkling wines. Two batches of sparkling wines were industrially produced, one with addition of bentonite to the tirage solution and the other without bentonite addition. Samples were taken at 20, 40, 90, 180, 270 and 365 days of aging with yeast. Total, free amino-, protein- and peptide-nitrogen concentrations were determined and foam properties and sensory quality were evaluated. It was observed that the bentonite retained part of the peptides and proteins and had an adverse effect on the sensory quality of the wine.