Improvement of acidification and sensory profile in Verdejo white wines through co-inoculation of Lachancea thermotolerans and Metschnikowia pulcherrima

Wineries in warm areas have had problems in winemaking due to rising grape pH as a result of the higher temperatures, which reduces the perception of freshness and has a negative impact on wine quality. To address this, biological acidification strategies have been implemented. This study evaluated the acidifying potential of two strains of Lachancea thermotolerans, Laktia and Blizz, which allow pH to be reduced by their ability to produce lactic acid. Microfermentations were performed using Verdejo grape must, with the strains tested alone and in co-inoculation with Meschnikowia pulcherrima (Mp29) and Hanseniaspora opuntiae (A56). Periodic analyses of oenological parameters by FTIR, lactic acid determinations, and microbiological analyses were carried out to evaluate yeast implantation and fermentative performance. Post fermentation, volatile compounds, redox potential, color, and sensory attributes were analyzed. The results indicated that the Blizz strain had the highest acidifying capacity, reaching 4.24 g/L. Co-inoculation with Mp29 enhanced lactic acid production, reaching 7.11 g/L. Sensory evaluation confirmed that tasters perceived the increased acidity positively, noting improvements in visual and aromatic qualities. Fermentations with Lachancea thermotolerans, especially in combination with strain Mp29, are an effective strategy to increase acidity in white wines, improving sensory properties and chemical characteristics in white wines.