Use of Lachancea thermotolerans for the Bioacidification of White Grape Musts: Assays from the Bench to the Cellar Scale

To date, there are no specific guidelines for the use of bioacidifying yeasts in winemaking. In this work, we aimed to characterize an oenological strain of Lachancea thermotolerans (Lt), a non-Saccharomyces lactic acid-producing yeast, and to test different sequential inoculation conditions with Saccharomyces cerevisiae (Sc). The results of bench scale vinifications showed that both the strategy of inoculating Sc 12 h after Lt and the mixing of Lt and Sc during fermentation delivered an acceptable increase in lactic acid (2 g/L) and a decrease in pH (about 0.15 units). Therefore, both strategies were implemented in winery experiments. Our results at the cellar scale showed no increase in acidity, which was likely due to the presence of indigenous yeasts. Overall, our experience shows the difficulty of translating laboratory protocols into cellar experiments and calls for further research into new strategies for implementing acidifying yeasts.