Winemaking enzymes

Glycosldases in winemaking. Enzyme treatment of juices or wines to increase the concentrations of volatile monoterpene flavorants could, if successful, provide considerable benefit to winemaking. 

Caridi, A., Galvano, F., Tafuri, A. Ritieni, A. (2006) Ochratoxin A removal during winemaking. Enzyme MIcrob. Technol. AO, 122-126. 

In enzymes, this folding process is crucial to their activity as catalysts, with part of the structure as the center of reactivity. Heating enzymes (or other treatments) destroys their three-dimensional structure so stops further action. For example, in winemaking, the rising alcohol content eventually denatures the enzymes responsible for turning sugar into alcohol, and fermentation stops. 

Dugelay, I. et al.. Role of cinnamoyl esterase activities from enzyme preparations on the formation of volatile phenols during winemaking. J. Agric. Food Chem. 41, 2092, 1993. 

A. Lupu, D. Compagnone and G. Palleschi, Screen-printed enzyme electrodes for the detection of marker analytes during winemaking, Anal. Chim. Acta, 513(1) (2004) 67-72. 

D. Moscone, Prussian Blue and enzyme bulk-modified screen-printed electrodes for hydrogen peroxide and glucose determination with improved storage and operational stability, Anal. Chim. Acta, 485 (2003) 111-120. A. Lupu, D. Compagnone and G. Palleschi, Screen-printed enzyme electrodes for the detection of marker analytes during winemaking, Anal. Chim. Acta, 513 (2004) 67-72. 

Trials performed on Shiraz for several years have allowed the comparison of wines produced under three winemaking protocols CM for 8 days (C) CM for 8 days, followed by a 10-day period with a daily pumping over—to maintain contact between harvest and free-run juice (P) same protocol as in P, but with the addition of pectolytic enzymes, before the first pumping over (P) (Flanzy et al., 2001). 

In the alcoholic fermentation of juice to wine, SO2 is added at the crushers at the rate of about one pound per one thousand gallons. Pectic enzymes may be added to increase juice yields and clarity. The fermentation is conducted with the native yeast of the grape or various pure culture strains of Saccaromyces cerevisiae. Whether or not yeast cultures are added depends on the quality of the grapes and the winemaker s preferences. Dehydrated wine yeast is in general use at the beginning of the crushing season. 

Addition of exogenous enzymes is currently the most commonly adopted practice in the wine industry to optimize the rate of enzymatic reactions taking place during winemaking. The large amount of research carried out on this topic has led to the presence of a considerable number of commercial preparations on the market, although in some areas, particularly protein stabilization of white wines, exogenous enzyme-based approaches have been unsuccessful so far. 

Developments of successful tools for the control of enzymatic reactions during winemaking, regardless of the type of method employed to optimize enzyme activity (e.g. exogenous enzymes, selected yeast and bacteria, or genetically enhanced microorganisms), will benefit from further improvements in the understanding of wine flavor chemistry and sensory perception. 

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