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Sucrose (common name: table sugar, also called saccharose) is a disaccharide of glucose and fructose with an α (alpha) 1,2 glycosidic linkage. The molecular formula of sucrose is C12H22O11. Its systematic name is β-D-fructofuranosyl-(2→1)-α-D-glucopyranoside (ending in "oside", because it's not a reducing sugar). It is best known for its role in human nutrition and is formed by plants but not by other organisms including animals. Pure sucrose is most often prepared as a fine, white, odorless, crystalline powder with a pleasing, sweet taste: the common table sugar. Sucrose is generally isolated from natural sources, however its chemical synthesis was first achieved in 1953 by Raymond Lemieux.
Like other carbohydrates, sucrose has a hydrogen to oxygen ratio of 2:1. It consists of two monosaccharides, α-glucose and fructose, joined by a glycosidic bond between carbon atom 1 of the glucose unit and carbon atom 2 of the fructose unit. What is notable about sucrose is that unlike most disaccharides, the glycosidic bond is formed between the reducing ends of both glucose and fructose, and not between the reducing end of one and the nonreducing end of the other. The effect of this inhibits further bonding to other saccharide units. Since it contains no anomeric hydroxyl groups, it is classified as a nonreducing sugar. Acidic hydrolysis can be used in laboratories to achieve the hydrolysis of sucrose into glucose and fructose.
Sucrose melts and decomposes at 186 °C (367 °F) to form caramel, and when combusted produces carbon, carbon dioxide, and water. Water breaks down sucrose by hydrolysis, however the process is so gradual that it could sit in solution for years with negligible change. If the enzyme sucrase is added however, the reaction will proceed rapidly.
