Winemaking, sparkling

Pozo-Bayon, M. A., Martinez-Rodriguez, A., Pueyo, E., and Moreno-Arribas, M. V. (2009). Chemical and biochemical features involved in sparkling wine production From a traditional to an improved winemaking technology. Trends Food Sci. Technol. 20,289-299. 

The nature of the still wine from which sparkling wine is made is an important, perhaps the most important, element in the quality of the final product. The character of the wine is based on the quality and degree of ripeness of the grapes selected and on the winemaking procedure. 

Casey, J. (1987). Effervescence in sparkling wines. Austr. Grapegr. Winemaker, 280, 55-62. 

Cations play a major role in winemaking. However, they must be monitored in view of the risk of turbidity, especially bitartrate with potassium, tartrate with calcium, ferric with trivalent iron, cuprous with the copper cation with a degree of oxidation of one. In sparkling wines, alkaline earth cations, especially magnesium, may have an effect on effervescence (Maujean et al., 1988). 

Finally, another defect well known to winemakers is the premature aging of bottled white wines. Although this has been associated with oxidative development, it has not been fully explained by enologists. This defect can affect any type of white wine, dry or sweet, still or sparkling, and whatever the grape variety or origin. It leads to the early disappearance of varietal aromas, the absence of reduction bouquet and, above all, the appearance of a characteristic, heavy smell, reminiscent of rancid beeswax, stale honey and, in extreme cases, naphthalene. Neither the compounds responsible for these odors, nor the mechanisms that produce them, nor the means of preventing this phenomenon, have yet been elucidated. 

Carbon dioxide produced by fermentation is known to have an inhibitory effect. This occurs during fermentations under pressure (sparkling wines). A slight internal pressure in the tank is sufficient to slow the fermentation, and above 7 bars fermentation becomes impossible. In normal winemaking conditions, carbon dioxide is released freely and exercises no inhibition on the fermentation. 

It is well known that the various stages in the winemaking process have an impact on foam quality. Robillard et al. (1993) examined the impact of filtering base wines. This operation removes solid or colloidal particles that provide a base for bubble formation (nucleation), considerably reducing the intensity of effervescence and thus, the foam stability of the corresponding sparkling wine. The smaller the pores of the filter medium, the more marked the impact on foam stability. 

BRS Lorena is an early Muscat grape cultivar recommended to Serra Gaficha for white and sparkling winemaking. It has also been successfully evaluated in tropical regions and organic systems. 

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