Biological aging acetaldehyde

During the biological aging of sherry, the concentration of ethanol decreases because of its consumption by flor yeast. Its respiration via the tricarboxylic acid pathway (Suarez-Lepez and Inigo-Leal, 2004) provides the main source of carbon and energy. Acetaldehyde is the main organic byproduct of ethanol metabolism, but other volatile compounds, notably acetic acid, butanediol, diacetyl, and acetoin, can also be formed. In addition,... 

The restrictive conditions of the biological aging process of wine (namely low pH, presence of sulphite, high ethanol and acetaldehyde concentrations, lack of sugars and low oxygen concentration) are compatible with only a few S. cerevisiae races. Also, the presence of specific flor races has been correlated with the aging stage of the wine and the sensory features of the end product (Mesa et al. 2000). 

Acetaldehyde is one of the most special compounds in the biological aging process and influences the sensory properties of wines by introducing a typical pungent... 

Acetaldehyde takes part in a number of reactions during the biological aging of wine one of the most important of which is the formation of 1,1-diethoxyethane. This acetal results from the combination of acetaldehyde and ethanol. Its concentration, which is closely related to those of the parent compounds, can easily exceed 100 mg/L (Munoz et al. 2005). Also, 1,1-diethoxyethane is the only acetal contributing to the aroma of wine (Etidvant 1991). 

Aranda, A., Querol, A., del Olmo, M. (2002). Correlation between acetaldehyde and ethanol resistance and expression of HSP genes in yeast strains isolated during the biological aging of sherry wines. Arch. Microbiol., 177, 304-312. 

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