`krōs), commonest of the sugars, a white, crystalline solid disaccharide (see carbohydrate carbohydrate, any member of a large class of chemical compounds that includes sugars, starches, cellulose, and related compounds. These compounds are produced naturally by green plants from carbon dioxide and water (see photosynthesis)...... Click the link for more information. ) with a sweet taste, melting and decomposing at 186°C; to form caramel. It is known commonly as cane sugar, beet sugar, or maple sugar, depending upon its natural source. It has the same empirical formula (C12H22O11) as lactose and maltose but differs from both in structure (see isomer isomer , in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of such compounds. Isomerism was first recognized by J. J. Berzelius in 1827.
..... Click the link for more information. ). Hydrolysis of sucrose yields D-glucose and D-fructose; the process is called inversion and the sugar mixture produced is known as invert sugar because, although sucrose itself rotates plane-polarized light to the right, the mixture "inverts" this light by rotating it to the left. Sucrose is obtained from the "juice" of sugarcane or the sugar beet and from the sap of the sugar maple. The cane or beets are crushed, and the juice, after treatment with lime to neutralize acids, is evaporated in vacuum pans that permit the process to be carried out at relatively low temperatures. The brownish liquid obtained, called molasses, evaporates further, leaving the sugar, brownish in color, which is dissolved in water, treated with animal charcoal to remove the color resulting from the presence of impurities, and recrystallized.
sucrose
or table sugarOrganic compound, colourless, sweet-tasting crystals that dissolve in water. Sucrose (C12H22O11) is a disaccharide; hydrolysis, by the enzyme invertase, yields “invert sugar” (so called because the hydrolysis results in an inversion of the rotation of plane polarized light), a 50:50 mixture of fructose and glucose, its two constituent monosaccharides. Sucrose occurs naturally in sugarcane, sugar beets, sugar-maple sap, dates, and honey. It is produced commercially in large amounts (especially from sugarcane and sugar beets) and is used almost entirely as food. See also sugar.
sucrose [′sü‚krōs]
Sucrose
An oligosaccharide, α- d -glucopyranosyl-β- d -fructofuranoside, also known as saccharose, cane sugar, or beet sugar. The structure is shown below.
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Sucrose
(also saccharose), one of the most important disac-charides. Sucrose, which is present in all photosynthesizing plants, forms colorless crystals that dissolve readily in water and melt at 185°–186°C. It is easily hydrolyzed to yield glucose and fructose by the action of acids or the enzyme invertase.
Sucrose is one of the most easily digested and transportable forms of carbohydrates in plants. Carbohydrates formed in photosynthesis are transferred in the form of sucrose from the leaves to seeds, roots, tubers, and bulbs, where the sucrose is easily converted into starch or inulin.
Sucrose was produced even in ancient India, China, and Egypt by separating it from the sap of sugarcane. Currently the major source of sucrose in countries of the temperate zone is the sugar beet. Sucrose is used widely in the food and microbiological industries. The fermentation of sucrose by various microorganisms yields ethyl alcohol, and other alcohols, acetone, acetic acid, lactic acid, and other products are obtained as well. Sucrose is commonly called sugar.
REFERENCCE
Kretovich, V. L. Osnovy biokhimii rastenii, 5th ed. Moscow, 1971.How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
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