Chapter 4 - Use of Non-Saccharomyces Yeasts in Red Winemaking

Abstract

Grape must is a complex matrix where grapes, microbes, and technological process determine the final composition of wine. In red wine vinification process the maceration during fermentation promotes the colonization of non-Saccharomyces yeasts widely present on the grape surface. These yeasts influence both the analytical composition and sensorial profile of final wine. In this regard, the use of selected non-Saccharomyces yeasts in mixed fermentations may positively contribute to enhance some desired characteristics of red wines. Non-Saccharomyces yeasts may be profitably used to enhance the aroma profile, to add complexity, and to reduce the ethanol content of wine. In addition, they can be involved in the stabilization of red wines by means of the release of polysaccharides and particularly of mannoproteins. The involvement of some non-Saccharomyces species during the red wine vinification significantly affects the total acidity of wine through the maloalcoholic fermentation or the production of large amounts of organic acids. Finally, some recent works highlighted the influence of these non-Saccharomyces yeasts on polyphenols composition and color stability of red wines. In this chapter, the role of the most studied non-Saccharomyces species will be discussed, focusing the attention on their contribution with commercial starters of Saccharomyces cerevisiae during wine fermentation.