Effect of interspecific yeast hybrids for secondary in-bottle alcoholic fermentation of English sparkling wines

AIM: In sparkling winemaking several yeasts can be used to perform the primary alcoholic fermentation that leads to the elaboration of the base wine. However, only a few Saccharomyces cerevisiae yeast strains are regularly used for the secondary in-bottle alcoholic fermentation 1. Recently, advances in yeast development programs have resulted in new breeds of interspecific wine yeast hybrids that ferment efficiently while producing novel flavours and aromas 2. In this work, sparkling wines produced using interspecific yeast hybrids for the secondary in-bottle alcoholic fermentation have been chemically and sensorially characterized. METHODS: Three commercial English base wines have been prepared for secondary in-bottle alcoholic fermentation with different yeast strains, including two commercial and several novel interspecific hybrids derived from Saccharomyces species not traditionally used in sparkling winemaking. After 12 months of lees ageing, the 14 wines produced were analysed for their chemical and macromolecular composition 3,4, phenolic profile 5, foaming and viscosity properties [6]. The analytical data were supplemented with a sensory analysis. RESULTS: The use of different strains on the three base wines resulted in differences in macromolecular content and sensory characteristics of wines. The foamability was mostly unaffected by the strain used, however some effect on foam stability was noticeable, likely due to the differences in polysaccharides released into the wines by the yeast strains. Chemically, the yeast strains did not result in significant differences upon on the main wine parameters, while the wines exhibited different sensory characteristics in terms of effervescence and pleasantness. CONCLUSIONS: Novel interspecific yeast hybrids can be used for the elaboration of sparkling wines as they provided wines with novel flavour and aroma attributes which affected sensory characteristics while retaining wine chemical characteristics similar to those of commonly used commercial Saccharomyces cerevisiae strains.