Wine Chemistry and Biochemistry

(Steven Felgate) #1
Chapter 7

Carbohydrates


M. Luz Sanz and Isabel Mart ́ınez-Castro


Contents


7.1 Introduction........................ ........................................ 231
7.2 ChemicalStructure.......................................................... 232
7.3 Properties.................................................................. 232
7.3.1 Isomerism............................................................ 232
7.3.2 Chemical Reactivity........... ........................................ 234
7.3.3 BiochemicalReactions ................................................. 238
7.3.4 PhysicalProperties .................................................... 238
7.4 Mono- and Disaccharides............ ........................................ 239
7.5 Polyalcohols....................... ........................................ 241
7.6 SugarAcids................................................................ 243
7.7 Polysaccharides..................... ........................................ 244
7.8 Conclusions................................................................ 246
References................................................................. 246


7.1 Introduction


Carbohydrates play an essential role in winery since they are the source of


fermentation giving rise to the production of alcohol. They also contribute to the


taste of wines conferring sweetness which varies from a background note in dry


wines to a clear taste in sweet wines; they also generate derived-products as glycerol


which gives body and roundness. Sugars also contribute to the aroma, through the


formation of some volatile compounds.


The name “carbohydrates” is derived from their origin: they are formed through


photosynthesis from CO 2 and water and their general formula is Cn(H 2 O)n or


Cn(H 2 O)n−xwhen they are constituted by polymers. Together with lipids and pro-


teins, carbohydrates are one of the main constituents of foods.


According to their polymerization degree, they can be classified as monosaccha-


rides, disaccharides, trisaccharides, etc., and polysaccharides.


M.LuzSanz(B)
Instituto de Qu ́ımica Org ́anica General (CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
e-mail: [email protected]


M.V. Moreno-Arribas, M.C. Polo (eds.),Wine Chemistry and Biochemistry,
DOI 10.1007/978-0-387-74118-510,©CSpringer Science+Business Media, LLC 2009


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