Improving white wine aroma and structure by non-Saccharomyces yeasts

The use of selected Saccharomyces cerevisiae starter strains in pure fermentation, is widely diffused in winemaking. Indeed, S. cerevisiae is able to suppress the wild microbial community and dominate the process. In the last years, however, there was a growing interest in the use of non-Saccharomyces yeast in winemaking. Several studies recognized a positive impact on wine complexity of non-Saccharomyces yeasts species in mixed and /or sequential fermentations with S. cerevisiae starter strains. These controlled mixed fermentations led an increase of important aroma compounds that affect the sensorial profile of wines particularly in white wines. Indeed, trend was evaluated in different musts of white grape varieties, such as Chardonnay, Sauvignon Blanc, Chenin blanc, Palomino and Verdicchio. The influence of non-Saccharomyces yeast culture with the yeast interactions in mixed fermentation can led the final product influencing both the analytical and aromatic profile. In addition, non-Saccharomyces yeast in mixed fermentation may contribute to control spoilage microorganisms and to reduce the ethanol content. In the present chapter, we describe the biotechnology of non-Saccharomyces yeast in the production of white wines, evaluating the interactions in mixed fermentation and focusing on their influence on aroma profile and structure of final product