Chemical winemakers

Fumaric Aero Inhibition. Another means of preventing malo-lactic fermentation is to add fumaric acid after alcoholic fermentation is complete (45, 46, 47,48). The inhibition is relative and its extent is dependent on the amount added. The susceptibility to fumaric acid is also dependent on the strain of malo-lactic bacteria tested (49). However, we know of no case where fumaric acid addition at the levels suggested by Cofran and Meyer (45) (about 0.05%) did not delay malo-lactic fermentation under normal winemaking conditions. This includes several experiments from our pilot winery (50). Nevertheless, we have not been hasty to recommend the use of fumaric acid as an inhibitor because 1) of the difficulty in solubilizing the acid in wine 2) we do not know the mechanism of action of its inhibition [Pilone (47, 48) has shown that the bacteria metabolize low levels of fumaric acid to lactic acid but, at inhibitory levels at wine pH, the acid is bactericidal] and 3) of the desirability of minimizing the use of chemical additives. 

Singleton, V.L. 1974, Analytical fractionation of the phenolic substances of grapes and wine and some practical uses of such analyses. In Chemistry of Winemaking (A.D. Webb, ed.) pp. 184-211. American Chemical Society, Washington, D.C. 

Pozo-Bayon, M. A., Martinez-Rodriguez, A., Pueyo, E., and Moreno-Arribas, M. V. (2009). Chemical and biochemical features involved in sparkling wine production From a traditional to an improved winemaking technology. Trends Food Sci. Technol. 20,289-299. 

Singleton, V. L. (1974). Some aspects of wooden container as a factor in wine maturation. In "Chemistry of Winemaking", A. D. Webb (Ed.), pp. 254-277. American Chemical society, Washington, DC. 

Q. alba (American oak) is used less frequently with white wines than red wines, and it is widely acknowledged that American oak has a distinctively different effect on wines chemical and sensory properties than does European oak. The strong and distinctive oakiness of Q. alba can overwhelm the varietal character of a white wine, if not used with care. Some winemakers combine use of both European and American oak in their oak-aging practices. 

The same chemical principles presented by the speakers on red (p. 59) and white table wine (p. 29) production are applicable to table wine production in the Interior Valley. Differences in the size of the winery operations and grape maturity are attributable to regional climatic conditions. With modern viticultural practices, the grapes grown for winemaking in this interior region now produce quality wines and they also comprise the largest volume of table wines produced in California. 

It is important to note that calling wine organic does not guarantee that it is 100% pure and free from pesticides and chemicals. The water the vines will use is likely to carry some pollution, there is the chance of spray drift from conventional vineyards nearby, and some chemicals are allowed in organic winemaking. Principally, organic... 

The aim of this book is to describe chemical and biochemical aspects of winemaking which are currently being researched. The areas of most interest at present and the subjects in which this interest is likely to continue or to increase in the following years have been selected. 

As well as fruity and buttery aromas, MLF has also been associated with other characteristic aromas such as floral, roasted, vanilla, sweet, woody, smoked, bitter, honey, etc. (Flenick-Kling 1993 Sauvageot and Vivier 1997). However, further studies are required to be able to relate the wine characteristics that are modified during malolactic fermentation with the production and/or degradation of a specific chemical compound by wine lactic acid bacteria. With this information, the winemaker can choose the best strain of lactic acid bacteria to obtain wine with a specific aroma or flavour. 

Wine is a complex mixture consisting of indigenous components and those obtained by chemical and biochemical transformations by wine microorganisms and/or during wine aging. Wine composition varies widely and is influenced by the grape (variety, quality) and by the winemaking conditions. 

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