Many years have been passed by since Dom Perignon had invited his brothers to taste the stars, yet we still continue to taste them. Not only tasting, we are drinking more and more sparkling wines every day.
According to OIV focus on sparkling wine market (OIV, 2014); along with the significant increase in the sparkling wine consumption, it is changing from being a festive consumption, to a more regular consumption. So, this change and increase made it crucial to study scientifically the quality and style of the sparkling wines. The producers are supposed to produce correspondent sparkling wine style and quality that will answer all the occasions of consumption. Starting from this point, I had actually created my thesis project. I will be introducing it you after giving a small summary of the traditional method of sparkling wine production.
One of the production methods of the natural sparkling wine is the traditional method, also known as “Champenoise method”, which is quite sophisticated since it requires a lot of labor and effort. The second fermentation which creates the bubbles and the aging on lees (the deposits of dead or residual yeast) are done inside of the actual bottle in which the sparkling wine will be sold. The aging on lees period may vary depending on the appellation, but generally the minimum is between 9 to 12 months while the maximum can be many years long. The sparkling wine, from the moment that it starts to ferment until the end of aging, is in contact with the lees (Ribéreau-Gayon et al., 2006).
It is not wrong to say that, the yeast selection for production of sparkling wines is one of the most crucial parts. The yeast that is used should have specific characteristics to be able to finish the second fermentation in the bottle. But apart from that, the yeasts can also change the organoleptic characteristics as texture and aromas of the sparkling wines (Suárez Lepe and Iñigo Leal, 2004). For that reason, the different yeast varieties might be used for improving different aspects of the sparkling wines. Starting from this idea, I had designed an experiment in laboratory of Universidad Politecnica de Madrid. I had chosen 3 different wine yeasts; one of them was Saccharomyces cerevisiae which is the most common yeast in enology. The others were non-Saccharomyces yeasts; Schizosaccharomyces pombe and Saccharomycodes ludwigii which have completely different metabolisms than Saccharomyces cerevisiae. I had carried out all the steps of the traditional method in laboratory conditions and I aged them on lees for 5 months.
After the aging process, I had organized a tasting where a panel of 11 experienced tasters evaluated the samples and observed the differences in the defined parameters. I had also conducted some chemical analyses in order to compare their analytical characteristics. Finally, I had obtained quite interesting results and differences in some of the attributes like color intensity, volatile compounds and acidity.
In the sparkling wines produced with different yeasts, different volatile compound profiles were detected, which give different aromas to the wine; like fruity, yeasty or buttery aromas. In the tasting panel, one of the yeasts was found to have higher aroma quality than the others. Although many organoleptic differences were found among the yeasts, the panel did not perceive any significant level on their total quality parameter. This result shows a positive side of the usage of different yeasts in traditional sparkling method, because it might be possible to change the aroma profile, without decreasing the overall quality.
The color parameter is important in rosé sparkling wines, since it shows a really different trend in different countries. For the markets which are more attracted by darker colors of rosé wines, it might be a good idea to use yeasts that would enhance the color during second fermentation and aging on lees. In this study, one of the yeasts showed a significantly darker color due to high anthocyanin content and it was also preferred by the tasting panel.
All in all, since nowadays, the quality and style of the sparkling wines are getting more important, it is useful to know the different ways to improve this product. I just gave one way of how to manage this, but nowadays many similar studies are being conducted in order to achieve the quality and uniqueness. It is important to keep updated with scientific knowledge in order to answer the demands of the market and produce a sparkling wine which will satisfy the customers.
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Ribéreau-Gayon P., Dubourdieu D., Donéche B., Lonvaud A. (2006). Handbook of Enology, Volume 1, The Microbiology of Wine and Vinifications. 2nd edition. John Wiley & Sons Ltd.
Suárez Lepe J.A., Iñigo Leal B. (2004). Microbiología Enológica, Fundamentos de Vinificación. 3rd edition. Ediciones Mundi-Prensa.