Yeast autolysis

Unfortunately, in spite of the published literature on wine proteins, we do not know the actual protein levels at which table or dessert wines are stable. The changes in protein content during production and processing of wines are still not known with sufficient accuracy to predict their behavior. The winemaker has to depend on empirical tests if he is to produce protein stable wines. Early separation of new wines from their fermentation yeast greatly improves their chances for protein stability by decreasing the release of yeast autolysis products into the wine. 

Martinez-Rodriguez, A. and Polo, M. C. (2000). Enological aspects of yeast autolysis. In "Recent Research Developments in Microbiology", (S. G. Pandalay, Ed.), Vol. 4, pp. 285-301. Research Signpost, Trivandrum. 

Pueyo, E., Marti nez-Rodriguez, A., Polo, M. C., Santa-Maria, G., and Bartolome, B. (2000). Release of lipids during yeast autolysis in a model wine system. ]. Agric. Food Chem. 48, 116-122. 

As described previously, during the elaboration of sparkling wines by the traditional method, an aging process takes place that is closely associated with the sensorial quality of the final wine. In fact, it is during this aging of sparkling wines that yeast autolysis takes place, by which the yeasts release intracellular compounds into the wine that can significantly alter its final composition (Charpentier and Feuillat 1993). 

Yeast autolysis could be defined as the hydrolysis of biopolymers under the action of hydrolytic enzymes which releases cytoplasmic (peptides, amino acids, fatty acids and nucleotides) and cell wall (glucans, mannoproteins) compounds into the wine (Alexandre et al. 2006).Usually, autolysis takes place at the end... 

Alexandre, H., Guilloux-Benatier, M. (2006). Yeast autolysis in sparkling wine - a review. Aust. J. Grape Wine Res., 12, 119-127. 

Cebollero, E., Carrascosa, A.V., and Gonzalez, R. (2005). Evidence for yeast autophagy during simulation of sparkling wine aging A reappraisal of the mechanism of yeast autolysis in wine. BiotechnoL Prog., 21, 614-616. 

Charpentier, C., Feuillat, M. (1993). Wine Microbiology and Biotechnology. In G.H. Fleet (Ed), Yeast autolysis (pp. 225-242).Chur Harwood Academic Publishers. 

Charpentier, C., Aussenac, J., Charpentier, M., Prome, J.C., Duteurtre, B., Feuillat, M. (2005). Release of nucleotides and nucleosides during yeast autolysis kinetics and potential impact on flavor. J. Agric. Food Chem., 53, 3000-3007. 

Connew, S. (1998). Yeast autolysis. A review of current rersearch. Aust. NZ Wine Ind. J., 13, 61-64. 

Fornairon-Bonnefond, C., Camarasa, C., Moutounet, M., Salmon, J.M. (2002). New trends on yeast autolysis and wine ageing on lees A bibliographic review. J. Int. Sci. Vigne Vin, 36, 49-69. 

Martinez-Rodriguez, A.J., and Polo, M.C. (2000b). Recent Res. Devel. Microbiology Volume 4. In S.G. Pandalai (Ed), Etiological aspects of yeast autolysis, (pp. 285-301). Trivandram Research Signpost. 

Yeast autolysis has a strong effect on the contents in higher alcohols, as shown by the presence of propanol, isobutanol and isoamyl alcohols in yeast extracts from wines under biological aging (Munoz et al. 2002). 

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