Non-Saccharomyces yeasts play a substantial role in the early stages of wine fermentation. With the increase in alcohol concentration, indigenous or commercial strains of Saccharomyces cerevisiae take over and complete the transformation of the grape must sugars into ethanol, CO2, and other secondary metabolites. The presence of non-Saccharomyces during the fermentation has an impact on the wine composition, and consequently, their contribution during the fermentation process cannot be ignored. The new challenges to enhance the appeal and value of wine elaborated by traditional technology are being achieved by selecting and using autochthonous non-Saccharomyces and Saccharomyces strains that may enhance regional identity of wines. Greater understanding of yeast biochemistry and physiology is enabling the selection and development of yeast strains that have defined specific influences on process efficiency and wine quality. The aim of this chapter was to show the different aspects of non-Saccharomyces species that may play a positive incidence in the biotechnological process to conduct to wine elaboration.
Part of the book: Grape and Wine Biotechnology
The effects of prefermentative cold skin-contact technique using Malvasia aromatica were studied as a first step to adapt to the climate change related effects in order to intensify the aroma potential of white wines of the D.O. “Vinos de Madrid” keeping the organoleptic characteristics of the region. Major volatile compounds were extracted by liquid–liquid extraction and quantified by GC-FID. Minor volatile compounds were determined by HS-SPME/GC–MS. Sensory analysis were also carried out to describe and quantify attributes of the wines. A total of 37 components were identified and quantified. Volatile components showed mixed behavior depending on the skin-contact time. Skin-contact for longer helps to enhance the floral character provided by some compounds contained in the skin, especially linalool and 2-phenyl etanol and were impact odorants of Malvasia aromatica wine based on odor activity values (OAVs).
Part of the book: Grapes and Wine