Yeasts in winemaking

Ciani, M., Comitini, F., Mannazzu, I., and Domizio, P. (2010). Controlled mixed culture fermentation A new perspective on the use of non-Saccharomyces yeasts in winemaking. FEMS Yeast Res. 10,123-133. 

Heard, G. (1999) Novel yeasts in winemaking -looking to the future. Food Australia, 51,347-352. 

Ross, J. P. (1997) Going wild wild yeast in winemaking. Wine and Vines, Sept., 16-21. 

The sugars in fruits such as grapes are feimented by yeasts to produce wines. In winemaking, lactic acid bacteria convert malic acid into lactic acid in malolactic fermentation in fruits with high acidity. Acetobacter and Gluconobacter oxidise ethanol in wine to acetic acid (vinegar). 

Pretorius, I. S. (2000). Tailoring wine yeast for the new millennium novel approaches to the ancient art in winemaking. Yeast 16, 675-729. 

In order to better manage winemaking and avoid defects, the use of selected starter yeast strains, suited to specific conditions, are a standard feature of modem in winemaking. These strains belong to the same yeast species usually found in spontaneous Amarone fermentations S. cerevisiae and S. bayanus. 

Sulphur dioxide (S02), the additive most commonly used and thought of in winemaking, can be used when the must is starting to ferment, to kill the yeasts, to fix the wine, to stop the fermentation, before bottling and to sterilise equipment. S02 can cause headaches, stomach-aches, hangovers and acute reactions in asthma sufferers. 

Radler, F. (1990a). Possible use of nisin in winemaking. 1. Action of nisin against lactic acid bacteria and wine yeasts in solid and liquid media Am. J. Enol. Vitic., 41, 1-6. 

Because grape must contain little organic sulfur, in the form of S-amino acids and glutathione, yeast assimilates sulfate, and sulfite when added, for the synthesis of organic sulfur compounds. Sulfur metabolism is important in winemaking since, depending on the yeast strain and nutrient composition, it is the source of mostly unpleasant compounds, including H2S and mercaptans (Rauhut 1993). 

Table 8D.4 Types of yeasts and starter cultures used in winemaking...

ComuzzD, P, Tat, L., Tonizzo, A., Battistutta, F. (2006). Yeast derivatives (extracts and autolysates) in winemaking Release of volatile compounds and effects on wine aroma volatility. Food Chem., 99, 217-230. 

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