Tailoring yeast and bacterial consortia to modulate wine fermentation profiles

Area of Science:

• Enology
• Microbiology
• Food Science

Background:

• Wine fermentation involves complex microbial interactions producing metabolites that affect wine quality.
• Aromatic amino acid-derived compounds (AADC) are key secondary metabolites influencing wine's sensory and health properties.
• Understanding yeast and lactic acid bacteria (LAB) roles is crucial for modulating wine's metabolic profile.

Purpose of the Study:

• To select specific yeast and LAB strains for enhanced production of tyrosol (TyrOH) and hydroxytyrosol (HT).
• To design and evaluate microbial consortia for improved AADC synthesis in wine.
• To investigate the impact of multi-species fermentation on wine composition and functionality.

Main Methods:

• Screening of Saccharomyces cerevisiae, non-Saccharomyces, and LAB strains for AADC production in enriched synthetic must.
• Quantification of TyrOH and HT production by selected strains.
• Implementation and monitoring of mixed fermentation strategies using selected yeast and LAB consortia, analyzing organic acids and microbial dynamics.

Main Results:

• Selected strains of S. cerevisiae, Zygosaccharomyces rouxii, and Oenococcus oeni demonstrated high AADC production potential.
• The combination of S. cerevisiae Lalvin CLOS and Z. rouxii CW96 yielded the highest hydroxytyrosol concentrations.
• Co-inoculations with LAB ensured efficient malolactic fermentation without increasing acetic acid levels.

Conclusions:

• Controlled multi-species fermentation represents a viable strategy to modulate wine's functional and metabolic profiles.
• Development of targeted microbial consortia can enhance the production of beneficial AADC compounds in wine.
• This approach offers potential for improving wine quality, stability, and bioactivity through microbial synergy.