The synergism between SO<SUB>2</SUB> and ethanol is the “villain” of yeasts at the beginning of the second fermentation of sparkling wines

Abstract

In our paper, we show that at a pH commonly found in sparkling base wines (i.e., 2.8-3.3), a synergism occurs between the SO2 added as a preservative and the ethanol present in the base wine. This synergism causes high stress on yeasts that lead to an important loss of viability, which in turn causes an increase in the lag phase time, slow fermentation and difficulties in finishing the prise de mousse.