Wine technology

Reactions of anthocyanins and flavanols take place much faster in the presence of acetaldehyde that is present in wine as a result of yeast metabolism and can also be produced through ethanol oxidation, especially in the presence of phenolic compounds, or introduced by addition of spirit in Port wine technology. The third mechanism proposed involves nucleophilic addition of the flavanol onto protonated acetaldehyde, followed by protonation and dehydration of the resulting adduct and nucleophilic addition of a second flavonoid onto the carbocation thus formed. The resulting products are anthocyanin flavanol adducts in which the flavonoid units are linked in C6 or C8 position through a methyl-methine bond, often incorrectly called ethyl-link in the literature. 

VVTinery quality control has not been formalized in the United States to the point where standard methods, practices, or performance criteria are established. The literature devotes little attention to the subject of wine production quality control, per se. The first survey of quality control in the California wine industry appeared as late as 1972 (I), and it is limited to sanitation aspects. One does not find chapters on quality control of winemaking in any of the major wine technology texts. 

Amerine, M.A. Joslyn, M.A. Table Wines Technology of Their Production, ... 

Ribereau-Gayon, P. 1985. New developments in wine technology. Am. J. Enol. Vitic. 36, 1-10. Rivas-Gonzalo, J.C., Santos-Hemandez, J.F., and Marine-Font, A. 1983. Study of the evolution of tyramine content during the vinification. J. Food Sci. 48, 417-418. 

Wine technology now requires various separation techniques which could profitably be replaced by membrane processes (2). 

Most of these efforts claimed possible indnstrial application of the immobilized biocatalysts due to their high operational stability, faster conversion of malic acid compared to free cells, and increased tolerance to SO2 and ethanol inhibition. Understanding the natnre and factors that affect MLF, which is a very complex process, as well as its effect on flavor formation, is crucial for optimizing wine technology and applying immobilization techniques at full scale. 

Spettoli, P., Bottacin, A., Nuti, M.P., and Zamorani, A. (1982) Immobilization of Leuconostoc oenos ML 34 in calcium alginate gels and its application to wine technology. Am. J. Enol Vitic., 33, 1-5. 

Gas Chromatography in Plant Science, Wine Technology, Toxicology and Some Specific Applications... 

Gas Chromatography in Plant Solenoe, Wine Technology, Toxioology and Some Speoifio Applioations... 

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