Replicative age differentially predicts metabolic competence across industrial yeasts at single-cell resolution.

Replicative age predicts metabolic decline in industrial yeasts, with viability dropping from 88% in young cells to 5% in oldest cells in S. pastorianus.

• Why it matters: Understanding how cell age affects metabolic function is crucial for optimizing fermentation processes, yet current methods fail to measure this link at the single-cell level across diverse strains.
• What they did: A dual-parameter flow cytometry method was developed, combining bud-scar labeling with viability assays, applied to four industrial yeast strains, including S. pastorianus and K. phaffii.
• The result: Findings show age-related viability declines are strain-specific, with S. pastorianus exhibiting a clear gradient, enabling more precise fermentation monitoring and yeast assessment for industry applications.