Impact of commercial cream yeast on acidity and sulphur dioxide combination in high-quality wines

The loss of acidity and pH increase in grapes and wines by accelerated ripening due to climate change represent key challenges for winemakers, especially in warm regions. Rapid sugar accumulation and sharp malic acid degradation result in wines with lower freshness, reduced microbiological stability, and diminished aging potential. While viticultural strategies likely require long-term implementation, oenological solutions such as bioacidification offer immediate impact on wine acidity. This study focuses on the use of specific Saccharomyces and non-Saccharomyces yeast strains in cream format that naturally impact increasing wine acidity while allowing to reduce the combination rate of sulphur dioxide. Studied cream yeasts developed by Bioenologia 2.0 showed the ability to increase total acidity between 0.8 to 1.4 g/L in reds with a consequent pH reduction around 0.36 units via activation of a proton pump mechanism from yeast. Cream yeasts also release significant amounts of glutathione, improving antioxidant capacity and contributing to lower sulphur dioxide combination, and increase the fresher aromatic profiles of wines. Obtained wines were basically and sensory characterized by accredited laboratory and sensory panels, respectively. Results confirm commercial cream yeasts are an effective biotechnological tool to overcome the effects of climate-driven grape ripening and to support the production of high-quality wines.