Chemical and biochemical features involved in sparkling wine production: from a traditional to an improved winemaking technology.

Sparkling wines produced by the traditional method owe their peculiar characteristics to a double process of fermentation and to the ageing with yeast that takes place in the same bottle that reaches the consumer. Special winemaking practices result in wines with distinct and unique characteristics, in which their study from a scientific, technological and economical point of view are very interesting. Over recent years, considerable progress has been made in understanding the biochemistry behind their production technology and their relationship with sensory characteristics. New scientific approaches based on modifications of yeast responsible for the second fermentation are being introduced, showing the interest for improvements in this traditional winemaking technology. The aim of this paper is to provide in a single review, an overall view of the current situation of knowledge of the chemical and biochemical aspects involved in this particular winemaking technology giving reference to interesting advances as well as future trends.