Influence of sequential inoculation of Wickerhamomyces anomalus and Saccharomyces cerevisiae in the quality of red wines

The use of mixed inoculation of non-Saccharomyces yeasts and S. cerevisiae in wine fermentations is of increasing interest for quality enhancement and improved complexity of wines. The effect of sequential inoculation of Wickerhamomyces anomalus (formerly Hansenula anomala) with interesting enological properties in terms of secondary metabolite production and a commercial S. cerevisiae strain in fermentation of non-sterilized red musts from Mazuela variety has been examined. The wines elaborated by sequential inoculation presented higher levels of acetates and ethyl esters, compounds that supply a fruity note, higher levels of lineal alcohols, which are responsible for herbaceous notes and lower concentrations of organic acids, that contribute to increase the aromatic quality, than wines produced by a S. cerevisiae monoculture. Both types of wines were comparable in levels of volatile acidity, glycerol, lactic acid and succinic acid produced. Sensory analysis showed that red wines obtained by mixed fermentations were preferred by 71.5 % of the tasters and were particularly appreciated for its floral and/or fruity notes.