Yeast autolysis in sparkling wine aging: Use of kille and sensitive Saccharomyces cerevisiae strains in co-culture

Background: Sparkling wines produced by traditional method owe their characteristics to secondary fermentation and maturation that occur during a slow ageing in bottles. Yeast autolysis plays an important role during the sparkling wine aging. Using a combina tion of killer and sensitive yeasts is possible to accelerate yeast autolysis and reduce maturing time. Methods: killer and sensitive Saccharomyces cerevisiae strains, separately and in co-cultures, were inoculated in base wine and bottled on pilot-plant scale. Commercial Saccaromyces bayanus strain was also investigated. Protein free amino acid and polysaccharides contents and sensory analysis were determined on the wine samples at 3, 6 and 9 months of aging. Yeast autolysis that occurs during the production of sparkling wines, obtained with co-cultures of killer and sensitive strains, has influenced free amino acids, total protein and polysaccharides content after 3 months aging time: sparkling wines, produced without the use of these yeasts, have reached the same results only after 9 months aging time. Results: These results demonstrate that killer and sensitive yeasts in co-culture can accelerate the onset of autoly‑sis in enological conditions, and has a positive effect on the quality of the aroma and flavor of sparkling wine. Conclusion: This paper offers an interesting biotechnological method to reduce production time of sparkling wine with economical benefits for the producers. We revised all patents relating to sparkling wine considering only those of interest for our study.