Combined Effects of Cold Pre-Fermentative Maceration and the Use of Non-Saccharomyces Yeasts (L. thermotolerans and T. delbrueckii) on the Composition of Cayetana Blanca Wines Produced in a Semi-Arid Climate

Climate change poses a major challenge for wine production in semi-arid regions, where grape ripening frequently leads to excessive sugar accumulation and reduced acidity. This study evaluated the combined effect of cold pre-fermentative maceration (PM) and the use of non-Saccharomyces yeasts (Lachancea thermotolerans and Torulaspora delbrueckii) on the composition and sensory properties of Cayetana Blanca wines. Pre-fermentative maceration increased titratable acidity by 0.5 g/L and yeast-assimilable nitrogen by 28 mg/L, creating more favorable conditions for the metabolic activity of non-Saccharomyces species. Wines fermented with L. thermotolerans—especially in sequential inoculation with S. cerevisiae after PM—showed the highest acidity and lactic acid content (2 g/L), together with 1% v/v lower ethanol and 1 g/L higher glycerol than the control. These wines were perceived as fresher and better balanced, despite a moderate decrease in fruity esters such as ethyl hexanoate, ethyl octanoate, and isoamyl acetate. Cluster analysis confirmed that non-Saccharomyces fermentations developed distinct compositional profiles only when combined with PM. Overall, the PM + L. thermotolerans + S. cerevisiae treatment achieved the most favorable balance between acidity, ethanol, and sensory freshness. This approach provides a sustainable and readily applicable method to enhance acidity and freshness in white wines from warm-climate regions.