Impact of Saccharomyces cerevisiae Strain Selection on Malolactic Fermentation by Lactobacillus plantarum and Oenococcus oeni

Simultaneous inoculation of yeast and lactic acid bacteria (LAB) is considered a state-of-the-art strategy to reduce overall vinification time and improve microbiological stability of wines. This inoculation protocol sparked interest in selecting yeast and LAB strains to modulate malic acid consumption rate and wine composition. The study presented here addresses the impact on malic acid consumption and metabolite production of combining Saccharomyces cerevisiae strains with different fermentation rates and nutrition demands with Lactobacillus plantarum and Oenococcus oeni strains. S. cerevisiae strains in pure culture fermentations without LAB inoculation exhibited different patterns of malic acid consumption rate and metabolite production. Simultaneous S. cerevisiae and LAB inoculation influenced the kinetics of lactic acid production and titratable acidity in a LAB-strain dependent manner. Wines undergoing malolactic fermentation with L. plantarum ML Prime finished faster and contained more L-lactic acid than similar wines inoculated with O. oeni Lalvin VP41; however, the degree of acidification depended on the S. cerevisiae strain used to conduct alcoholic fermentation. This study reveals new knowledge about the use of L. plantarum in winemaking and shows the effect of S. cerevisiae strains with different enological characteristics, with or without LAB co-inoculation, on wine composition.