Effect of Variety, Year, and Grape Maturity on the Kinetics of Alcoholic Fermentation

¹ Institut Supérieur de la Vigne et du Vin, INRA - IPV, Laboratoire de Microbiologie et Technologie des Fermentations, 2 place Viala, 34060 Montpellier Cédex 1, France

The effect of variety, year, and grape maturity on fermentation kinetics was studied. The differences were quantified by comparing the values of the maximum CO₂ production rates ((dCO₂/dt)_max) and the trends of the (dCO₂/dt) curves at the end of fermentation. Fermentation kinetics were very different among grape varieties, but also changed significantly with year and maturity. Year above all influenced the maximum CO₂ production rate (dCO₂/dt)_max) when maturity dramatically changed the kinetics at the end of fermentation. Kinetic variations were also related to must composition changes. The maximum CO₂ production rate was correlated to the must assimilable nitrogen concentration while the trend of the dCO₂/dt curve at the end of fermentation (expressed as DM80) was above all a function of the sugar concentration.

Key words: kinetics, fermentation

Submitted on May 31, 1995