Effect of Time of Bacterial Inoculation on the Stimulation of Malo-Lactic Fermentation

Abstract

Malo-lactic fermentation was induced in two red table wines made from French hybrid grapes in 1976 and 1977. The wines were inoculated with Leuconostoc oenos PSU-1 (2% v/v) before, during, and after alcoholic fermentation. In general, inoculation before alcoholic fermentation did not stimulate malo-lactic fermentation. The time required to complete malo-lactic fermentation for the control wines was essentially the same as for those wines inoculated before yeast fermentation. In contrast, malo-lactic fermentation was stimulated in all wines inoculated during and after fermentation. Most wines inoculated after fermentation completed malo-lactic fermentation in approximately the same length of time as wines inoculated during fermentation. However, a greater stimulation of this secondary fermentation occurred in Chelois wines inoculated after yeast fermentation. Malic acid content in the malo-lactic wines was 0.02% or less.