Abstract
Acetic acid is the main component of the volatile acidity of grape musts and wines. It can be formed as a by-product of alcoholic fermentation or as a product of the metabolism of acetic and lactic acid bacteria, which can metabolize residual sugars to increase volatile acidity. Acetic acid has a negative impact on yeast fermentative performance and affects the quality of certain types of wine when present above a given concentration. In this mini-review, we present an overview of fermentation conditions and grape-must composition favoring acetic acid formation, as well the metabolic pathways leading to its formation and degradation by yeast. The negative effect of acetic acid on the fermentative performance of Saccharomyces cerevisiae will also be covered, including its role as a physiological inducer of apoptosis. Finally, currently available wine deacidification processes and new proposed solutions based on zymological deacidification by select S. cerevisiae strains will be discussed.
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This work was funded by the portuguese research agency (Fundação para a Ciência e Técnologia - FCT) through the Centre of Molecular and Environmental Biology - University of Minho (CBMA-UM), and the Institute for Biotechnology and Bioengineering, Centre of Genetics and Biotechnology (IBB/CGB-UTAD), by the projects PTDC/AGRALI/71460/2006, POCI/AGR/56102/2004, and PTDC/AGR-ALI/103392/2008 from FCT. Research leading to this work has also received funding from the European Community's Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 232454.
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Vilela-Moura, A., Schuller, D., Mendes-Faia, A. et al. The impact of acetate metabolism on yeast fermentative performance and wine quality: reduction of volatile acidity of grape musts and wines. Appl Microbiol Biotechnol 89, 271–280 (2011). https://doi.org/10.1007/s00253-010-2898-3
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DOI: https://doi.org/10.1007/s00253-010-2898-3