Physicochemical and Organoleptic Differences in Chardonnay Chilean Wines after Ethanol Reduction Practises: Pre-Fermentative Water Addition or Metschnikowia pulcherrima

Climate change is posing a major challenge to the wine industry, with rising alcohol levels emerging as an issue of concern affecting quality, economics and health. This study explores two methods to reduce alcohol content in Chardonnay wines from Chile. Firstly, 5% and 10% of water was added to grape must. Secondly, the sequential inoculation of Metschnikowia pulcherrima with Saccharomyces cerevisiae was examined. The main objectives were to assess the efficacy of these treatments in reducing alcohol levels and their impact on organoleptic properties. Our findings revealed that the presence of M. pulcherrima in winery conditions was less effective in reducing ethanol. Nevertheless, wines resulting from this treatment exhibited an interesting composition with distinct sensory profiles. Furthermore, the Sc-5% W condition displayed promising results by reducing ethanol content by 0.47% (v/v), with less significant changes in the sensory profile. Although the Sc-10% W wines showed a more substantial ethanol reduction of 1.73% (v/v), they exhibited a decreasing trend in volatile compounds and polysaccharides, ultimately being perceived as less complex in sensory analysis and not being preferred by consumers. This research contributes to understanding how these approaches affect the alcohol content and sensory attributes of white wines and is fundamental to the sustainability of the sector and the ability of the sector to recover from climate challenges.