Unveiling the influence of autochthonous yeasts selected from spontaneous fermentation of cachaça on ethanol, ester and fermentation kinetics.

Autochthonous yeasts from cachaça productions are not well known compared to industrial Saccharomyces cerevisiae strains. Although yeast diversity some in spontaneous sugarcane fermentations have been examined, their metabolic roles, adaptation mechanisms, and effects on ethanol and aroma formation remain largely unexplored. This study aims to investigate the influence of autochthonous yeasts selected from the spontaneous fermentations of cachaça on ethanol, ester and fermentation kinetics, evaluating their metabolic diversity and potential contribution to the aromatic complexity of the beverage. Fermentations were conducted in synthetic must (15°Brix) with yeast concentration (YC) levels of 90 × 10⁷, 120 × 10⁷, and 150 × 10⁷ cells/mL at 30 °C for 24 h. Higher YC accelerated fermentation but reduced ethanol and ester formation, while lower YC enhanced ethanol and ester production with lower acidity. PCA revealed significant correlations between physicochemical and kinetic parameters, indicating that alkaline conditions favor alcohol and ester production. These findings improve fermentation control, contribute to yeast strain databases, and support the sugar-alcohol industry as part of Paraíba's and Brazil's cultural and economic heritage.